v3.3.0

Closes #327

.editorconfig

@@ -7,8 +7,7 @@ insert_final_newline = true
 charset = utf-8
 trim_trailing_whitespace = true
 indent_style = tab
-indent_size = 8
 
-[*.{md,yml}]
+[*.{md,yml,yaml,json,toml,htm,html}]
 indent_style = space
 indent_size = 2

.github/CODE_OF_CONDUCT.md

@@ -0,0 +1,46 @@
+# Contributor Covenant Code of Conduct
+
+## Our Pledge
+
+In the interest of fostering an open and welcoming environment, we as contributors and maintainers pledge to making participation in our project and our community a harassment-free experience for everyone, regardless of age, body size, disability, ethnicity, gender identity and expression, level of experience, nationality, personal appearance, race, religion, or sexual identity and orientation.
+
+## Our Standards
+
+Examples of behavior that contributes to creating a positive environment include:
+
+* Using welcoming and inclusive language
+* Being respectful of differing viewpoints and experiences
+* Gracefully accepting constructive criticism
+* Focusing on what is best for the community
+* Showing empathy towards other community members
+
+Examples of unacceptable behavior by participants include:
+
+* The use of sexualized language or imagery and unwelcome sexual attention or advances
+* Trolling, insulting/derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or electronic address, without explicit permission
+* Other conduct which could reasonably be considered inappropriate in a professional setting
+
+## Our Responsibilities
+
+Project maintainers are responsible for clarifying the standards of acceptable behavior and are expected to take appropriate and fair corrective action in response to any instances of unacceptable behavior.
+
+Project maintainers have the right and responsibility to remove, edit, or reject comments, commits, code, wiki edits, issues, and other contributions that are not aligned to this Code of Conduct, or to ban temporarily or permanently any contributor for other behaviors that they deem inappropriate, threatening, offensive, or harmful.
+
+## Scope
+
+This Code of Conduct applies both within project spaces and in public spaces when an individual is representing the project or its community. Examples of representing a project or community include using an official project e-mail address, posting via an official social media account, or acting as an appointed representative at an online or offline event. Representation of a project may be further defined and clarified by project maintainers.
+
+## Enforcement
+
+Instances of abusive, harassing, or otherwise unacceptable behavior may be reported by contacting the project team at andrey.nering@gmail.com. The project team will review and investigate all complaints, and will respond in a way that it deems appropriate to the circumstances. The project team is obligated to maintain confidentiality with regard to the reporter of an incident. Further details of specific enforcement policies may be posted separately.
+
+Project maintainers who do not follow or enforce the Code of Conduct in good faith may face temporary or permanent repercussions as determined by other members of the project's leadership.
+
+## Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage], version 1.4, available at [http://contributor-covenant.org/version/1/4][version]
+
+[homepage]: http://contributor-covenant.org
+[version]: http://contributor-covenant.org/version/1/4/

.github/CONTRIBUTING.md

@@ -0,0 +1,6 @@
+* Bug reports and feature requests are welcome in [the issues][issues]
+* Pull Requests are welcome. For more complex changes and features it's
+  recommended to open an issue with the feature request first
+* Documentation contributions are as important as code contributions
+
+[issues]: https://github.com/go-task/task/issues

.github/FUNDING.yml

@@ -0,0 +1,3 @@
+open_collective: task
+patreon: andreynering
+custom: 'https://www.paypal.com/cgi-bin/webscr?cmd=_donations&business=GSVDU63RKG45A&currency_code=BRL&source=url'

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,14 @@
+---
+name: Bug Report
+about: Use the template to report bugs and issues
+labels: bug
+---
+
+- Task version:
+- Operating System:
+
+### Example Taskfile showing the issue
+
+```yaml
+
+```

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,5 @@
+blank_issues_enabled: false
+contact_links:
+  - name: Questions, Ideas and General Discussions
+    url: https://github.com/go-task/task/discussions
+    about: Ask questions and discuss general ideas with the community

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,12 @@
+---
+name: Feature Request
+about: Use the template to make feature requests
+labels: feature
+---
+
+Describe in detail what feature do you want to see in Task.
+Give examples if possible.
+
+Please, search if this wasn't proposed before, and if this is more like an idea
+than a strong feature request, consider opening a
+[discussion](https://github.com/go-task/task/discussions) instead.

.github/workflows/release.yml

@@ -0,0 +1,26 @@
+name: goreleaser
+
+on:
+  push:
+    tags:
+      - '*'
+
+jobs:
+  goreleaser:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v1
+
+      - name: Set up Go
+        uses: actions/setup-go@v1
+        with:
+          go-version: 1.15.x
+
+      - name: Run GoReleaser
+        uses: goreleaser/goreleaser-action@v1
+        with:
+          version: latest
+          args: release --rm-dist
+        env:
+          GITHUB_TOKEN: ${{secrets.GITHUB_TOKEN}}

.github/workflows/test.yml

@@ -0,0 +1,30 @@
+name: Test
+on: [push, pull_request]
+jobs:
+  test:
+    name: Test
+    strategy:
+      matrix:
+        go-version: [1.14.x, 1.15.x]
+        platform: [ubuntu-latest, macos-latest, windows-latest]
+    runs-on: ${{matrix.platform}}
+    steps:
+      - name: Set up Go ${{matrix.go-version}}
+        uses: actions/setup-go@v1
+        with:
+          go-version: ${{matrix.go-version}}
+        id: go
+
+      - name: Check out code into the Go module directory
+        uses: actions/checkout@v1
+
+      - name: Download Go modules
+        run: go mod download
+        env:
+          GOPROXY: https://proxy.golang.org
+
+      - name: Build
+        run: go build -o ./bin/task -v ./cmd/task
+
+      - name: Test
+        run: ./bin/task test

.gitignore

@@ -14,3 +14,17 @@
 .glide/
 
 ./task
+.task
+dist/
+
+.DS_Store
+
+# intellij idea/goland
+.idea/
+
+# exuberant ctags
+tags
+
+/bin
+/testdata/vars/v1
+/tmp

.goreleaser.yml

@@ -0,0 +1,47 @@
+build:
+  binary: task
+  main: cmd/task/task.go
+  goos:
+    - windows
+    - darwin
+    - linux
+  goarch:
+    - 386
+    - amd64
+    - arm
+    - arm64
+  goarm:
+    - 6
+  ignore:
+    - goos: darwin
+      goarch: 386
+  env:
+    - CGO_ENABLED=0
+
+archives:
+  - name_template: "{{.Binary}}_{{.Os}}_{{.Arch}}"
+    format_overrides:
+      - goos: windows
+        format: zip
+
+release:
+  draft: true
+
+snapshot:
+  name_template: "{{.Tag}}"
+
+checksum:
+  name_template: "task_checksums.txt"
+
+nfpms:
+  - vendor: Task
+    homepage: https://github.com/go-task/task
+    maintainer: Andrey Nering <andrey.nering@gmail.com>
+    description: Simple task runner written in Go
+    license: MIT
+    conflicts:
+      - taskwarrior
+    formats:
+      - deb
+      - rpm
+    file_name_template: "{{.ProjectName}}_{{.Os}}_{{.Arch}}"

CHANGELOG.md

@@ -0,0 +1,348 @@
+# Changelog
+
+## v3.3.0 - 2021-03-20
+
+- Add support for delegating CLI arguments to commands with `--` and a
+  special `CLI_ARGS` variable
+  ([#327](https://github.com/go-task/task/issues/327)).
+- Add a `--concurrency` (alias `-C`) flag, to limit the number of tasks that
+  run concurrently. This is useful for heavy workloads.
+  ([#345](https://github.com/go-task/task/pull/345)).
+
+## v3.2.2 - 2021-01-12
+
+- Improve performance of `--list` and `--summary` by skipping running shell
+  variables for these flags
+  ([#332](https://github.com/go-task/task/issues/332)).
+- Fixed a bug where an environment in a Taskfile was not always overridable
+  by the system environment
+  ([#425](https://github.com/go-task/task/issues/425)).
+- Fixed environment from .env files not being available as variables
+  ([#379](https://github.com/go-task/task/issues/379)).
+- The install script is now working for ARM platforms
+  ([#428](https://github.com/go-task/task/pull/428)).
+
+## v3.2.1 - 2021-01-09
+
+- Fixed some bugs and regressions regarding dynamic variables and directories
+  ([#426](https://github.com/go-task/task/issues/426)).
+- The [slim-sprig](https://github.com/go-task/slim-sprig) package was updated
+  with the upstream [sprig](https://github.com/Masterminds/sprig).
+
+## v3.2.0 - 2021-01-07
+
+- Fix the `.task` directory being created in the task directory instead of the
+  Taskfile directory
+  ([#247](https://github.com/go-task/task/issues/247)).
+- Fix a bug where dynamic variables (those declared with `sh:`) were not
+  running in the task directory when the task has a custom dir or it was
+  in an included Taskfile
+  ([#384](https://github.com/go-task/task/issues/384)).
+- The watch feature (via the `--watch` flag) got a few different bug fixes and
+  should be more stable now
+  ([#423](https://github.com/go-task/task/pull/423), [#365](https://github.com/go-task/task/issues/365)).
+
+## v3.1.0 - 2021-01-03
+
+- Fix a bug when the checksum up-to-date resolution is used by a task
+  with a custom `label:` attribute
+  ([#412](https://github.com/go-task/task/issues/412)).
+- Starting from this release, we're releasing official ARMv6 and ARM64 binaries
+  for Linux
+  ([#375](https://github.com/go-task/task/issues/375), [#418](https://github.com/go-task/task/issues/418)).
+- Task now respects the order of declaration of included Taskfiles when
+  evaluating variables declaring by them
+  ([#393](https://github.com/go-task/task/issues/393)).
+- `set -e` is now automatically set on every command. This was done to fix an
+  issue where multiline string commands wouldn't really fail unless the
+  sentence was in the last line
+  ([#403](https://github.com/go-task/task/issues/403)).
+
+## v3.0.1 - 2020-12-26
+
+- Allow use as a library by moving the required packages out of the `internal`
+  directory
+  ([#358](https://github.com/go-task/task/pull/358)).
+- Do not error if a specified dotenv file does not exist
+  ([#378](https://github.com/go-task/task/issues/378), [#385](https://github.com/go-task/task/pull/385)).
+- Fix panic when you have empty tasks in your Taskfile
+  ([#338](https://github.com/go-task/task/issues/338), [#362](https://github.com/go-task/task/pull/362)).
+
+## v3.0.0 - 2020-08-16
+
+- On `v3`, all CLI variables will be considered global variables
+  ([#336](https://github.com/go-task/task/issues/336), [#341](https://github.com/go-task/task/pull/341))
+- Add support to `.env` like files
+  ([#324](https://github.com/go-task/task/issues/324), [#356](https://github.com/go-task/task/pull/356)).
+- Add `label:` to task so you can override the task name in the logs
+  ([#321](https://github.com/go-task/task/issues/321]), [#337](https://github.com/go-task/task/pull/337)).
+- Refactor how variables work on version 3
+  ([#311](https://github.com/go-task/task/pull/311)).
+- Disallow `expansions` on v3 since it has no effect.
+- `Taskvars.yml` is not automatically included anymore.
+- `Taskfile_{{OS}}.yml` is not automatically included anymore.
+- Allow interpolation on `includes`, so you can manually include a Taskfile
+  based on operation system, for example.
+- Expose `.TASK` variable in templates with the task name
+  ([#252](https://github.com/go-task/task/issues/252)).
+- Implement short task syntax
+  ([#194](https://github.com/go-task/task/issues/194), [#240](https://github.com/go-task/task/pull/240)).
+- Added option to make included Taskfile run commands on its own directory
+  ([#260](https://github.com/go-task/task/issues/260), [#144](https://github.com/go-task/task/issues/144))
+- Taskfiles in version 1 are not supported anymore
+  ([#237](https://github.com/go-task/task/pull/237)).
+- Added global `method:` option. With this option, you can set a default
+  method to all tasks in a Taskfile
+  ([#246](https://github.com/go-task/task/issues/246)).
+- Changed default method from `timestamp` to `checksum`
+  ([#246](https://github.com/go-task/task/issues/246)).
+- New magic variables are now available when using `status:`:
+  `.TIMESTAMP` which contains the greatest modification date
+  from the files listed in `sources:`, and `.CHECKSUM`, which
+  contains a checksum of all files listed in `status:`.
+  This is useful for manual checking when using external, or even remote,
+  artifacts when using `status:`
+  ([#216](https://github.com/go-task/task/pull/216)).
+- We're now using [slim-sprig](https://github.com/go-task/slim-sprig) instead of
+  [sprig](https://github.com/Masterminds/sprig), which allowed a file size
+  reduction of about 22%
+  ([#219](https://github.com/go-task/task/pull/219)).
+- We now use some colors on Task output to better distinguish message types -
+  commands are green, errors are red, etc
+  ([#207](https://github.com/go-task/task/pull/207)).
+
+## v2.8.1 - 2020-05-20
+
+- Fix error code for the `--help` flag
+  ([#300](https://github.com/go-task/task/issues/300), [#330](https://github.com/go-task/task/pull/330)).
+- Print version to stdout instead of stderr
+  ([#299](https://github.com/go-task/task/issues/299), [#329](https://github.com/go-task/task/pull/329)).
+- Supress `context` errors when using the `--watch` flag
+  ([#313](https://github.com/go-task/task/issues/313), [#317](https://github.com/go-task/task/pull/317)).
+- Support templating on description
+  ([#276](https://github.com/go-task/task/issues/276), [#283](https://github.com/go-task/task/pull/283)).
+
+## v2.8.0 - 2019-12-07
+
+- Add `--parallel` flag (alias `-p`) to run tasks given by the command line in
+  parallel
+  ([#266](https://github.com/go-task/task/pull/266)).
+- Fixed bug where calling the `task` CLI only informing global vars would not
+  execute the `default` task.
+- Add hability to silent all tasks by adding `silent: true` a the root of the
+  Taskfile.
+
+## v2.7.1 - 2019-11-10
+
+- Fix error being raised when `exit 0` was called
+  ([#251](https://github.com/go-task/task/issues/251)).
+
+## v2.7.0 - 2019-09-22
+
+- Fixed panic bug when assigning a global variable
+  ([#229](https://github.com/go-task/task/issues/229), [#243](https://github.com/go-task/task/issues/234)).
+- A task with `method: checksum` will now re-run if generated files are deleted
+  ([#228](https://github.com/go-task/task/pull/228), [#238](https://github.com/go-task/task/issues/238)).
+
+## v2.6.0 - 2019-07-21
+
+- Fixed some bugs regarding minor version checks on `version:`.
+- Add `preconditions:` to task
+  ([#205](https://github.com/go-task/task/pull/205)).
+- Create directory informed on `dir:` if it doesn't exist
+  ([#209](https://github.com/go-task/task/issues/209), [#211](https://github.com/go-task/task/pull/211)).
+- We now have a `--taskfile` flag (alias `-t`), which can be used to run
+  another Taskfile (other than the default `Taskfile.yml`)
+  ([#221](https://github.com/go-task/task/pull/221)).
+- It's now possible to install Task using Homebrew on Linux
+  ([go-task/homebrew-tap#1](https://github.com/go-task/homebrew-tap/pull/1)).
+
+## v2.5.2 - 2019-05-11
+
+- Reverted YAML upgrade due issues with CRLF on Windows
+  ([#201](https://github.com/go-task/task/issues/201), [go-yaml/yaml#450](https://github.com/go-yaml/yaml/issues/450)).
+- Allow setting global variables through the CLI
+  ([#192](https://github.com/go-task/task/issues/192)).
+
+## 2.5.1 - 2019-04-27
+
+- Fixed some issues with interactive command line tools, where sometimes
+  the output were not being shown, and similar issues
+  ([#114](https://github.com/go-task/task/issues/114), [#190](https://github.com/go-task/task/issues/190), [#200](https://github.com/go-task/task/pull/200)).
+- Upgraded [go-yaml/yaml](https://github.com/go-yaml/yaml) from v2 to v3.
+
+## v2.5.0 - 2019-03-16
+
+- We moved from the taskfile.org domain to the new fancy taskfile.dev domain.
+  While stuff is being redirected, we strongly recommend to everyone that use
+  [this install script](https://taskfile.dev/#/installation?id=install-script)
+  to use the new taskfile.dev domain on scripts from now on.
+- Fixed to the ZSH completion
+  ([#182](https://github.com/go-task/task/pull/182)).
+- Add [`--summary` flag along with `summary:` task attribute](https://taskfile.org/#/usage?id=display-summary-of-task)
+  ([#180](https://github.com/go-task/task/pull/180)).
+
+## v2.4.0 - 2019-02-21
+
+- Allow calling a task of the root Taskfile from an included Taskfile
+  by prefixing it with `:`
+  ([#161](https://github.com/go-task/task/issues/161), [#172](https://github.com/go-task/task/issues/172)),
+- Add flag to override the `output` option
+  ([#173](https://github.com/go-task/task/pull/173));
+- Fix bug where Task was persisting the new checksum on the disk when the Dry
+  Mode is enabled
+  ([#166](https://github.com/go-task/task/issues/166));
+- Fix file timestamp issue when the file name has spaces
+  ([#176](https://github.com/go-task/task/issues/176));
+- Mitigating path expanding issues on Windows
+  ([#170](https://github.com/go-task/task/pull/170)).
+
+## v2.3.0 - 2019-01-02
+
+- On Windows, Task can now be installed using [Scoop](https://scoop.sh/)
+  ([#152](https://github.com/go-task/task/pull/152));
+- Fixed issue with file/directory globing
+  ([#153](https://github.com/go-task/task/issues/153));
+- Added ability to globally set environment variables
+  (
+    [#138](https://github.com/go-task/task/pull/138),
+    [#159](https://github.com/go-task/task/pull/159)
+  ).
+
+## v2.2.1 - 2018-12-09
+
+- This repository now uses Go Modules (#143). We'll still keep the `vendor` directory in sync for some time, though;
+- Fixing a bug when the Taskfile has no tasks but includes another Taskfile (#150);
+- Fix a bug when calling another task or a dependency in an included Taskfile (#151).
+
+## v2.2.0 - 2018-10-25
+
+- Added support for [including other Taskfiles](https://taskfile.org/#/usage?id=including-other-taskfiles) (#98)
+  - This should be considered experimental. For now, only including local files is supported, but support for including remote Taskfiles is being discussed. If you have any feedback, please comment on #98.
+- Task now have a dedicated documentation site: https://taskfile.org
+  - Thanks to [Docsify](https://docsify.js.org/) for making this pretty easy. To check the source code, just take a look at the [docs](https://github.com/go-task/task/tree/master/docs) directory of this repository. Contributions to the documentation is really appreciated.
+
+## v2.1.1 - 2018-09-17
+
+- Fix suggestion to use `task --init` not being shown anymore (when a `Taskfile.yml` is not found)
+- Fix error when using checksum method and no file exists for a source glob (#131)
+- Fix signal handling when the `--watch` flag is given (#132)
+
+## v2.1.0 - 2018-08-19
+
+- Add a `ignore_error` option to task and command (#123)
+- Add a dry run mode (`--dry` flag) (#126)
+
+## v2.0.3 - 2018-06-24
+
+- Expand environment variables on "dir", "sources" and "generates" (#116)
+- Fix YAML merging syntax (#112)
+- Add ZSH completion (#111)
+- Implement new `output` option. Please check out the [documentation](https://github.com/go-task/task#output-syntax)
+
+## v2.0.2 - 2018-05-01
+
+- Fix merging of YAML anchors (#112)
+
+## v2.0.1 - 2018-03-11
+
+- Fixes panic on `task --list`
+
+## v2.0.0 - 2018-03-08
+
+Version 2.0.0 is here, with a new Taskfile format.
+
+Please, make sure to read the [Taskfile versions](https://github.com/go-task/task/blob/master/TASKFILE_VERSIONS.md) document, since it describes in depth what changed for this version.
+
+* New Taskfile version 2 (https://github.com/go-task/task/issues/77)
+* Possibility to have global variables in the `Taskfile.yml` instead of `Taskvars.yml` (https://github.com/go-task/task/issues/66)
+* Small improvements and fixes
+
+## v1.4.4 - 2017-11-19
+
+- Handle SIGINT and SIGTERM (#75);
+- List: print message with there's no task with description;
+- Expand home dir ("~" symbol) on paths (#74);
+- Add Snap as an installation method;
+- Move examples to its own repo;
+- Watch: also walk on tasks called on on "cmds", and not only on "deps";
+- Print logs to stderr instead of stdout (#68);
+- Remove deprecated `set` keyword;
+- Add checksum based status check, alternative to timestamp based.
+
+## v1.4.3 - 2017-09-07
+
+- Allow assigning variables to tasks at run time via CLI (#33)
+- Added suport for multiline variables from sh (#64)
+- Fixes env: remove square braces and evaluate shell (#62)
+- Watch: change watch library and few fixes and improvements
+- When use watching, cancel and restart long running process on file change (#59 and #60)
+
+## v1.4.2 - 2017-07-30
+
+- Flag to set directory of execution
+- Always echo command if is verbose mode
+- Add silent mode to disable echoing of commands
+- Fixes and improvements of variables (#56)
+
+## v1.4.1 - 2017-07-15
+
+- Allow use of YAML for dynamic variables instead of $ prefix
+  - `VAR: {sh: echo Hello}` instead of `VAR: $echo Hello`
+- Add `--list` (or `-l`) flag to print existing tasks
+- OS specific Taskvars file (e.g. `Taskvars_windows.yml`, `Taskvars_linux.yml`, etc)
+- Consider task up-to-date on equal timestamps (#49)
+- Allow absolute path in generates section (#48)
+- Bugfix: allow templating when calling deps (#42)
+- Fix panic for invalid task in cyclic dep detection
+- Better error output for dynamic variables in Taskvars.yml (#41)
+- Allow template evaluation in parameters
+
+## v1.4.0 - 2017-07-06
+
+- Cache dynamic variables
+- Add verbose mode (`-v` flag)
+- Support to task parameters (overriding vars) (#31) (#32)
+- Print command, also when "set:" is specified (#35)
+- Improve task command help text (#35)
+
+## v1.3.1 - 2017-06-14
+
+- Fix glob not working on commands (#28)
+- Add ExeExt template function
+- Add `--init` flag to create a new Taskfile
+- Add status option to prevent task from running (#27)
+- Allow interpolation on `generates` and `sources` attributes (#26)
+
+## v1.3.0 - 2017-04-24
+
+- Migrate from os/exec.Cmd to a native Go sh/bash interpreter
+  - This is a potentially breaking change if you use Windows.
+  - Now, `cmd` is not used anymore on Windows. Always use Bash-like syntax for your commands, even on Windows.
+- Add "ToSlash" and "FromSlash" to template functions
+- Use functions defined on github.com/Masterminds/sprig
+- Do not redirect stdin while running variables commands
+- Using `context` and `errgroup` packages (this will make other tasks to be cancelled, if one returned an error)
+
+## v1.2.0 - 2017-04-02
+
+- More tests and Travis integration
+- Watch a task (experimental)
+- Possibility to call another task
+- Fix "=" not being reconized in variables/environment variables
+- Tasks can now have a description, and help will print them (#10)
+- Task dependencies now run concurrently
+- Support for a default task (#16)
+
+## v1.1.0 - 2017-03-08
+
+- Support for YAML, TOML and JSON (#1)
+- Support running command in another directory (#4)
+- `--force` or `-f` flag to force execution of task even when it's up-to-date
+- Detection of cyclic dependencies (#5)
+- Support for variables (#6, #9, #14)
+- Operation System specific commands and variables (#13)
+
+## v1.0.0 - 2017-02-28
+
+- Add LICENSE file

README.md

@@ -1,108 +1,15 @@
-# Task - Simple "Make" alternative
+<div align="center">
+  <a href="https://taskfile.dev">
+    <img src="docs/Logo.png" width="200px" height="200px" />
+  </a>
 
-Task is a simple tool that allows you to easily run development and build
-tasks. Task is written in Go, but can be used to develop any language.
-It aims to be simpler and easier to use then [GNU Make][make].
+  <h1>Task</h1>
 
-## Installation
+  <p>
+    Task is a task runner / build tool that aims to be simpler and easier to use than, for example, <a href="https://www.gnu.org/software/make/">GNU Make<a>.
+  </p>
 
-If you have a Go environment setup, you can simply run:
-
-```bash
-go get -u -v github.com/go-task/task/cmd/task
-```
-
-Now the `task` executable should be available in your `PATH`.
-
-## Usage
-
-Create a file called `Taskfile.yml`. The `cmds` key should contains the
-commands of a task:
-
-```yml
-build:
-  cmds:
-    - go build -v -i main.go
-
-assets:
-  cmds:
-    - gulp
-```
-
-Running the tasks is as simple as running:
-
-```bash
-task assets build
-```
-
-If Bash is available (Linux and Windows while on Git Bash), the commands will
-run in Bash, otherwise will run on `cmd` (Windows).
-
-### Task dependencies
-
-You may have tasks that depends on others. Just point them on `deps` will run
-them automatically:
-
-```yml
-build:
-  deps: [assets]
-  cmds:
-    - go build -v -i main.go
-
-assets:
-  cmds:
-    - gulp
-```
-
-In the above example, `assets` will always run right before `build` if you run
-`task build`.
-
-A task can have only dependencies and no commands to group tasks together:
-
-```yml
-assets:
-  deps: [js, css]
-
-js:
-  cmds:
-    - npm run buildjs
-
-css:
-  cmds:
-    - npm run buildcss
-```
-
-### Prevent task from running when not necessary
-
-If a task generates something, you can inform Task the source and generated
-files, to Task will prevent to run them if not necessary.
-
-```yml
-build:
-  deps: [js, css]
-  cmds:
-    - go build -v -i main.go
-
-js:
-  cmds:
-    - npm run buildjs
-  sources:
-    - js/src/**/*.js
-  generates:
-    - public/bundle.js
-
-css:
-  cmds:
-    - npm run buildcss
-  sources:
-    - css/src/*.css
-  generates:
-    - public/bundle.css
-```
-
-`sources` and `generates` should be file patterns. When both are given, Task
-will compare the modification date/time of the files to determine if it's
-necessary to run the task. If not, it will just print
-`Task "js" is up to date`.
-
-[make]: https://www.gnu.org/software/make/
+  <p>
+    See <a href="https://taskfile.dev">taskfile.dev</a> for the documentation.
+  </p>
+</div>

Taskfile.yml

@@ -0,0 +1,83 @@
+version: '3'
+
+includes:
+  docs:
+    taskfile: ./docs
+    dir: ./docs
+
+vars:
+  GIT_COMMIT:
+    sh: git log -n 1 --format=%h
+
+  GO_PACKAGES:
+    sh: go list ./...
+
+env:
+  CGO_ENABLED: '0'
+
+tasks:
+  default:
+    cmds:
+      - task: test
+
+  install:
+    desc: Installs Task
+    cmds:
+      - go install -v -ldflags="-w -s -X main.version={{.GIT_COMMIT}}" ./cmd/task
+
+  mod:
+    desc: Downloads and tidy Go modules
+    cmds:
+      - go mod download
+      - go mod tidy
+
+  cli-deps:
+    desc: Downloads CLI dependencies
+    cmds:
+      - task: go-get
+        vars: {REPO: golang.org/x/lint/golint}
+      - task: go-get
+        vars: {REPO: github.com/goreleaser/goreleaser}
+      - task: go-get
+        vars: {REPO: github.com/goreleaser/godownloader}
+
+  clean:
+    desc: Cleans temp files and folders
+    cmds:
+      - rm -rf dist/
+
+  lint:
+    desc: Runs golint
+    cmds:
+      - golint {{catLines .GO_PACKAGES}}
+    silent: true
+
+  test:
+    desc: Runs test suite
+    deps: [install]
+    cmds:
+      - go test {{catLines .GO_PACKAGES}}
+
+  test-release:
+    desc: Tests release process without publishing
+    cmds:
+      - goreleaser --snapshot --rm-dist
+
+  gen-install-script:
+    desc: Generate install script using https://github.com/goreleaser/godownloader
+    cmds:
+      - godownloader --repo go-task/task -o install-task.sh
+      - cp ./install-task.sh ./docs/install.sh
+
+  ci:
+    - task: go-get
+      vars: {REPO: golang.org/x/lint/golint}
+    - task: lint
+    - task: test
+
+  go-get: go get -u {{.REPO}}
+
+  packages:
+    cmds:
+      - echo '{{.GO_PACKAGES}}'
+    silent: true

args/args.go

@@ -0,0 +1,64 @@
+package args
+
+import (
+	"strings"
+
+	"github.com/go-task/task/v3/taskfile"
+)
+
+// ParseV3 parses command line argument: tasks and global variables
+func ParseV3(args ...string) ([]taskfile.Call, *taskfile.Vars) {
+	var calls []taskfile.Call
+	var globals = &taskfile.Vars{}
+
+	for _, arg := range args {
+		if !strings.Contains(arg, "=") {
+			calls = append(calls, taskfile.Call{Task: arg})
+			continue
+		}
+
+		name, value := splitVar(arg)
+		globals.Set(name, taskfile.Var{Static: value})
+	}
+
+	if len(calls) == 0 {
+		calls = append(calls, taskfile.Call{Task: "default"})
+	}
+
+	return calls, globals
+}
+
+// ParseV2 parses command line argument: tasks and vars of each task
+func ParseV2(args ...string) ([]taskfile.Call, *taskfile.Vars) {
+	var calls []taskfile.Call
+	var globals = &taskfile.Vars{}
+
+	for _, arg := range args {
+		if !strings.Contains(arg, "=") {
+			calls = append(calls, taskfile.Call{Task: arg})
+			continue
+		}
+
+		if len(calls) < 1 {
+			name, value := splitVar(arg)
+			globals.Set(name, taskfile.Var{Static: value})
+		} else {
+			if calls[len(calls)-1].Vars == nil {
+				calls[len(calls)-1].Vars = &taskfile.Vars{}
+			}
+			name, value := splitVar(arg)
+			calls[len(calls)-1].Vars.Set(name, taskfile.Var{Static: value})
+		}
+	}
+
+	if len(calls) == 0 {
+		calls = append(calls, taskfile.Call{Task: "default"})
+	}
+
+	return calls, globals
+}
+
+func splitVar(s string) (string, string) {
+	pair := strings.SplitN(s, "=", 2)
+	return pair[0], pair[1]
+}

args/args_test.go

@@ -0,0 +1,209 @@
+package args_test
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"github.com/go-task/task/v3/args"
+	"github.com/go-task/task/v3/taskfile"
+)
+
+func TestArgsV3(t *testing.T) {
+	tests := []struct {
+		Args            []string
+		ExpectedCalls   []taskfile.Call
+		ExpectedGlobals *taskfile.Vars
+	}{
+		{
+			Args: []string{"task-a", "task-b", "task-c"},
+			ExpectedCalls: []taskfile.Call{
+				{Task: "task-a"},
+				{Task: "task-b"},
+				{Task: "task-c"},
+			},
+		},
+		{
+			Args: []string{"task-a", "FOO=bar", "task-b", "task-c", "BAR=baz", "BAZ=foo"},
+			ExpectedCalls: []taskfile.Call{
+				{Task: "task-a"},
+				{Task: "task-b"},
+				{Task: "task-c"},
+			},
+			ExpectedGlobals: &taskfile.Vars{
+				Keys: []string{"FOO", "BAR", "BAZ"},
+				Mapping: map[string]taskfile.Var{
+					"FOO": taskfile.Var{Static: "bar"},
+					"BAR": taskfile.Var{Static: "baz"},
+					"BAZ": taskfile.Var{Static: "foo"},
+				},
+			},
+		},
+		{
+			Args: []string{"task-a", "CONTENT=with some spaces"},
+			ExpectedCalls: []taskfile.Call{
+				{Task: "task-a"},
+			},
+			ExpectedGlobals: &taskfile.Vars{
+				Keys: []string{"CONTENT"},
+				Mapping: map[string]taskfile.Var{
+					"CONTENT": taskfile.Var{Static: "with some spaces"},
+				},
+			},
+		},
+		{
+			Args: []string{"FOO=bar", "task-a", "task-b"},
+			ExpectedCalls: []taskfile.Call{
+				{Task: "task-a"},
+				{Task: "task-b"},
+			},
+			ExpectedGlobals: &taskfile.Vars{
+				Keys: []string{"FOO"},
+				Mapping: map[string]taskfile.Var{
+					"FOO": {Static: "bar"},
+				},
+			},
+		},
+		{
+			Args: nil,
+			ExpectedCalls: []taskfile.Call{
+				{Task: "default"},
+			},
+		},
+		{
+			Args: []string{},
+			ExpectedCalls: []taskfile.Call{
+				{Task: "default"},
+			},
+		},
+		{
+			Args: []string{"FOO=bar", "BAR=baz"},
+			ExpectedCalls: []taskfile.Call{
+				{Task: "default"},
+			},
+			ExpectedGlobals: &taskfile.Vars{
+				Keys: []string{"FOO", "BAR"},
+				Mapping: map[string]taskfile.Var{
+					"FOO": {Static: "bar"},
+					"BAR": {Static: "baz"},
+				},
+			},
+		},
+	}
+
+	for i, test := range tests {
+		t.Run(fmt.Sprintf("TestArgs%d", i+1), func(t *testing.T) {
+			calls, globals := args.ParseV3(test.Args...)
+			assert.Equal(t, test.ExpectedCalls, calls)
+			if test.ExpectedGlobals.Len() > 0 || globals.Len() > 0 {
+				assert.Equal(t, test.ExpectedGlobals, globals)
+			}
+		})
+	}
+}
+
+func TestArgsV2(t *testing.T) {
+	tests := []struct {
+		Args            []string
+		ExpectedCalls   []taskfile.Call
+		ExpectedGlobals *taskfile.Vars
+	}{
+		{
+			Args: []string{"task-a", "task-b", "task-c"},
+			ExpectedCalls: []taskfile.Call{
+				{Task: "task-a"},
+				{Task: "task-b"},
+				{Task: "task-c"},
+			},
+		},
+		{
+			Args: []string{"task-a", "FOO=bar", "task-b", "task-c", "BAR=baz", "BAZ=foo"},
+			ExpectedCalls: []taskfile.Call{
+				{
+					Task: "task-a",
+					Vars: &taskfile.Vars{
+						Keys: []string{"FOO"},
+						Mapping: map[string]taskfile.Var{
+							"FOO": taskfile.Var{Static: "bar"},
+						},
+					},
+				},
+				{Task: "task-b"},
+				{
+					Task: "task-c",
+					Vars: &taskfile.Vars{
+						Keys: []string{"BAR", "BAZ"},
+						Mapping: map[string]taskfile.Var{
+							"BAR": taskfile.Var{Static: "baz"},
+							"BAZ": taskfile.Var{Static: "foo"},
+						},
+					},
+				},
+			},
+		},
+		{
+			Args: []string{"task-a", "CONTENT=with some spaces"},
+			ExpectedCalls: []taskfile.Call{
+				{
+					Task: "task-a",
+					Vars: &taskfile.Vars{
+						Keys: []string{"CONTENT"},
+						Mapping: map[string]taskfile.Var{
+							"CONTENT": taskfile.Var{Static: "with some spaces"},
+						},
+					},
+				},
+			},
+		},
+		{
+			Args: []string{"FOO=bar", "task-a", "task-b"},
+			ExpectedCalls: []taskfile.Call{
+				{Task: "task-a"},
+				{Task: "task-b"},
+			},
+			ExpectedGlobals: &taskfile.Vars{
+				Keys: []string{"FOO"},
+				Mapping: map[string]taskfile.Var{
+					"FOO": {Static: "bar"},
+				},
+			},
+		},
+		{
+			Args: nil,
+			ExpectedCalls: []taskfile.Call{
+				{Task: "default"},
+			},
+		},
+		{
+			Args: []string{},
+			ExpectedCalls: []taskfile.Call{
+				{Task: "default"},
+			},
+		},
+		{
+			Args: []string{"FOO=bar", "BAR=baz"},
+			ExpectedCalls: []taskfile.Call{
+				{Task: "default"},
+			},
+			ExpectedGlobals: &taskfile.Vars{
+				Keys: []string{"FOO", "BAR"},
+				Mapping: map[string]taskfile.Var{
+					"FOO": {Static: "bar"},
+					"BAR": {Static: "baz"},
+				},
+			},
+		},
+	}
+
+	for i, test := range tests {
+		t.Run(fmt.Sprintf("TestArgs%d", i+1), func(t *testing.T) {
+			calls, globals := args.ParseV2(test.Args...)
+			assert.Equal(t, test.ExpectedCalls, calls)
+			if test.ExpectedGlobals.Len() > 0 || globals.Len() > 0 {
+				assert.Equal(t, test.ExpectedGlobals, globals)
+			}
+
+		})
+	}
+}

cmd/task/task.go

@@ -1,9 +1,219 @@
 package main
 
 import (
-	"github.com/go-task/task"
+	"context"
+	"fmt"
+	"log"
+	"os"
+	"os/signal"
+	"path/filepath"
+	"strings"
+	"syscall"
+
+	"github.com/spf13/pflag"
+
+	"github.com/go-task/task/v3"
+	"github.com/go-task/task/v3/args"
+	"github.com/go-task/task/v3/internal/logger"
+	"github.com/go-task/task/v3/taskfile"
 )
 
+var (
+	version = "master"
+)
+
+const usage = `Usage: task [-ilfwvsd] [--init] [--list] [--force] [--watch] [--verbose] [--silent] [--dir] [--taskfile] [--dry] [--summary] [task...]
+
+Runs the specified task(s). Falls back to the "default" task if no task name
+was specified, or lists all tasks if an unknown task name was specified.
+
+Example: 'task hello' with the following 'Taskfile.yml' file will generate an
+'output.txt' file with the content "hello".
+
+'''
+version: '3'
+tasks:
+  hello:
+    cmds:
+      - echo "I am going to write a file named 'output.txt' now."
+      - echo "hello" > output.txt
+    generates:
+      - output.txt
+'''
+
+Options:
+`
+
 func main() {
-	task.Run()
+	log.SetFlags(0)
+	log.SetOutput(os.Stderr)
+
+	pflag.Usage = func() {
+		log.Print(usage)
+		pflag.PrintDefaults()
+	}
+
+	var (
+		versionFlag bool
+		helpFlag    bool
+		init        bool
+		list        bool
+		status      bool
+		force       bool
+		watch       bool
+		verbose     bool
+		silent      bool
+		dry         bool
+		summary     bool
+		parallel    bool
+		concurrency int
+		dir         string
+		entrypoint  string
+		output      string
+		color       bool
+	)
+
+	pflag.BoolVar(&versionFlag, "version", false, "show Task version")
+	pflag.BoolVarP(&helpFlag, "help", "h", false, "shows Task usage")
+	pflag.BoolVarP(&init, "init", "i", false, "creates a new Taskfile.yml in the current folder")
+	pflag.BoolVarP(&list, "list", "l", false, "lists tasks with description of current Taskfile")
+	pflag.BoolVar(&status, "status", false, "exits with non-zero exit code if any of the given tasks is not up-to-date")
+	pflag.BoolVarP(&force, "force", "f", false, "forces execution even when the task is up-to-date")
+	pflag.BoolVarP(&watch, "watch", "w", false, "enables watch of the given task")
+	pflag.BoolVarP(&verbose, "verbose", "v", false, "enables verbose mode")
+	pflag.BoolVarP(&silent, "silent", "s", false, "disables echoing")
+	pflag.BoolVarP(&parallel, "parallel", "p", false, "executes tasks provided on command line in parallel")
+	pflag.BoolVar(&dry, "dry", false, "compiles and prints tasks in the order that they would be run, without executing them")
+	pflag.BoolVar(&summary, "summary", false, "show summary about a task")
+	pflag.StringVarP(&dir, "dir", "d", "", "sets directory of execution")
+	pflag.StringVarP(&entrypoint, "taskfile", "t", "", `choose which Taskfile to run. Defaults to "Taskfile.yml"`)
+	pflag.StringVarP(&output, "output", "o", "", "sets output style: [interleaved|group|prefixed]")
+	pflag.BoolVarP(&color, "color", "c", true, "colored output")
+	pflag.IntVarP(&concurrency, "concurrency", "C", 0, "limit number tasks to run concurrently")
+	pflag.Parse()
+
+	if versionFlag {
+		fmt.Printf("Task version: %s\n", version)
+		return
+	}
+
+	if helpFlag {
+		pflag.Usage()
+		return
+	}
+
+	if init {
+		wd, err := os.Getwd()
+		if err != nil {
+			log.Fatal(err)
+		}
+		if err := task.InitTaskfile(os.Stdout, wd); err != nil {
+			log.Fatal(err)
+		}
+		return
+	}
+
+	if dir != "" && entrypoint != "" {
+		log.Fatal("task: You can't set both --dir and --taskfile")
+		return
+	}
+	if entrypoint != "" {
+		dir = filepath.Dir(entrypoint)
+		entrypoint = filepath.Base(entrypoint)
+	} else {
+		entrypoint = "Taskfile.yml"
+	}
+
+	e := task.Executor{
+		Force:       force,
+		Watch:       watch,
+		Verbose:     verbose,
+		Silent:      silent,
+		Dir:         dir,
+		Dry:         dry,
+		Entrypoint:  entrypoint,
+		Summary:     summary,
+		Parallel:    parallel,
+		Color:       color,
+		Concurrency: concurrency,
+
+		Stdin:  os.Stdin,
+		Stdout: os.Stdout,
+		Stderr: os.Stderr,
+
+		OutputStyle: output,
+	}
+	if err := e.Setup(); err != nil {
+		log.Fatal(err)
+	}
+	v, err := e.Taskfile.ParsedVersion()
+	if err != nil {
+		log.Fatal(err)
+		return
+	}
+
+	if list {
+		e.PrintTasksHelp()
+		return
+	}
+
+	var (
+		calls                 []taskfile.Call
+		globals               *taskfile.Vars
+		tasksAndVars, cliArgs = getArgs()
+	)
+
+	if v >= 3.0 {
+		calls, globals = args.ParseV3(tasksAndVars...)
+	} else {
+		calls, globals = args.ParseV2(tasksAndVars...)
+	}
+
+	globals.Set("CLI_ARGS", taskfile.Var{Static: strings.Join(cliArgs, " ")})
+	e.Taskfile.Vars.Merge(globals)
+
+	ctx := context.Background()
+	if !watch {
+		ctx = getSignalContext()
+	}
+
+	if status {
+		if err := e.Status(ctx, calls...); err != nil {
+			log.Fatal(err)
+		}
+		return
+	}
+
+	if err := e.Run(ctx, calls...); err != nil {
+		e.Logger.Errf(logger.Red, "%v", err)
+		os.Exit(1)
+	}
+}
+
+func getArgs() (tasksAndVars, cliArgs []string) {
+	var (
+		args          = pflag.Args()
+		doubleDashPos = pflag.CommandLine.ArgsLenAtDash()
+	)
+
+	if doubleDashPos != -1 {
+		tasksAndVars = args[:doubleDashPos]
+		cliArgs = args[doubleDashPos:]
+	} else {
+		tasksAndVars = args
+	}
+
+	return
+}
+
+func getSignalContext() context.Context {
+	ch := make(chan os.Signal, 1)
+	signal.Notify(ch, os.Interrupt, os.Kill, syscall.SIGTERM)
+	ctx, cancel := context.WithCancel(context.Background())
+	go func() {
+		sig := <-ch
+		log.Printf("task: signal received: %s", sig)
+		cancel()
+	}()
+	return ctx
 }

completion/bash/task.bash

@@ -0,0 +1,21 @@
+_task_completion()
+{
+  local scripts;
+  local curr_arg;
+
+  # Remove colon from word breaks
+  COMP_WORDBREAKS=${COMP_WORDBREAKS//:}
+
+  scripts=$(task -l | sed '1d' | awk '{ print $2 }' | sed 's/:$//');
+
+  curr_arg="${COMP_WORDS[COMP_CWORD]:-"."}"
+
+  # Do not accept more than 1 argument
+  if [ "${#COMP_WORDS[@]}" != "2" ]; then
+    return
+  fi
+
+  COMPREPLY=($(compgen -c | echo "$scripts" | grep $curr_arg));
+}
+
+complete -F _task_completion task

completion/fish/task.fish

@@ -0,0 +1,24 @@
+function __task_get_tasks --description "Prints all available tasks with their description"
+	task -l | sed '1d' | awk '{ $1=""; print $0 }' | tr ': ', '\t' | string trim
+end
+
+complete -c task -d 'Runs the specified task(s). Falls back to the "default" task if no task name was specified, or lists all tasks if an unknown task name was 
+specified.' -xa "(__task_get_tasks)"
+
+
+complete -c task -s c -l color     -d 'colored output (default true)'
+complete -c task -s d -l dir       -d 'sets directory of execution'
+complete -c task      -l dry       -d 'compiles and prints tasks in the order that they would be run, without executing them'
+complete -c task -s f -l force     -d 'forces execution even when the task is up-to-date'
+complete -c task -s h -l help      -d 'shows Task usage'
+complete -c task -s i -l init      -d 'creates a new Taskfile.yml in the current folder'
+complete -c task -s l -l list      -d 'lists tasks with description of current Taskfile'
+complete -c task -s o -l output    -d 'sets output style: [interleaved|group|prefixed]' -xa "interleaved group prefixed"
+complete -c task -s p -l parallel  -d 'executes tasks provided on command line in parallel'
+complete -c task -s s -l silent    -d 'disables echoing'
+complete -c task      -l status    -d 'exits with non-zero exit code if any of the given tasks is not up-to-date'
+complete -c task      -l summary   -d 'show summary about a task'
+complete -c task -s t -l taskfile  -d 'choose which Taskfile to run. Defaults to "Taskfile.yml"'
+complete -c task -s v -l verbose   -d 'enables verbose mode'
+complete -c task      -l version   -d 'show Task version'
+complete -c task -s w -l watch     -d 'enables watch of the given task'

completion/ps/task.ps1

@@ -0,0 +1,10 @@
+$scriptBlock = {
+	param($commandName, $wordToComplete, $cursorPosition)
+	$curReg = "task{.exe}? (.*?)$"
+	$startsWith = $wordToComplete | Select-String $curReg -AllMatches | ForEach-Object { $_.Matches.Groups[1].Value }
+	$reg = "\* ($startsWith.+?):"
+	$listOutput = $(task -l)
+	$listOutput | Select-String $reg -AllMatches | ForEach-Object { $_.Matches.Groups[1].Value + " " }
+}
+
+Register-ArgumentCompleter -Native -CommandName task -ScriptBlock $scriptBlock

completion/zsh/_task

@@ -0,0 +1,25 @@
+#compdef task
+
+# Listing commands from Taskfile.yml
+function __list() {
+    local -a scripts
+
+    if [ -f Taskfile.yml ]; then
+        scripts=($(task -l | sed '1d' | sed 's/^\* //' | awk '{ print $1 }' | sed 's/:$//' | sed 's/:/\\:/g'))
+        _describe 'script' scripts
+    fi
+}
+
+_arguments \
+    '(-d --dir)'{-d,--dir}': :_files' \
+    '(--dry)'--dry \
+    '(-f --force)'{-f,--force} \
+    '(-i --init)'{-i,--init} \
+    '(-l --list)'{-l,--list} \
+    '(-s --silent)'{-s,--silent} \
+    '(--status)'--status \
+    '(-v --verbose)'{-v,--verbose} \
+    '(--version)'--version \
+    '(-w --watch)'{-w,--watch} \
+    '(- *)'{-h,--help} \
+    '*: :__list' \

concurrency.go

@@ -0,0 +1,25 @@
+package task
+
+func (e *Executor) acquireConcurrencyLimit() func() {
+	if e.concurrencySemaphore == nil {
+		return emptyFunc
+	}
+
+	e.concurrencySemaphore <- struct{}{}
+	return func() {
+		<-e.concurrencySemaphore
+	}
+}
+
+func (e *Executor) releaseConcurrencyLimit() func() {
+	if e.concurrencySemaphore == nil {
+		return emptyFunc
+	}
+
+	<-e.concurrencySemaphore
+	return func() {
+		e.concurrencySemaphore <- struct{}{}
+	}
+}
+
+func emptyFunc() {}

docs/CNAME

@@ -0,0 +1 @@
+taskfile.dev

docs/README.md

@@ -0,0 +1,51 @@
+# Task
+
+<div align="center">
+  <img id="logo" src="/Logo.png" height="250px" width="250px" />
+</div>
+
+Task is a task runner / build tool that aims to be simpler and easier to use
+than, for example, [GNU Make][make].
+
+Since it's written in [Go][go], Task is just a single binary and has no other
+dependencies, which means you don't need to mess with any complicated install
+setups just to use a build tool.
+
+Once [installed](installation.md), you just need to describe your build tasks
+using a simple [YAML][yaml] schema in a file called `Taskfile.yml`:
+
+```yaml
+version: '3'
+
+tasks:
+  hello:
+    cmds:
+      - echo 'Hello World from Task!'
+    silent: true
+```
+
+And call it by running `task hello` from you terminal.
+
+The above example is just the start, you can take a look at the [usage](usage.md)
+guide to check the full schema documentation and Task features.
+
+## Features
+
+- [Easy installation](installation.md): just download a single binary, add to
+  $PATH and you're done! Or you can also install using [Homebrew][homebrew],
+  [Snapcraft][snapcraft], or [Scoop][scoop] if you want;
+- Available on CIs: by adding [this simple command](installation.md#install-script)
+  to install on your CI script and you're done to use Task as part of your CI pipeline;
+- Truly cross-platform: while most build tools only work well on Linux or macOS,
+  Task also supports Windows thanks to [this awesome shell interpreter for Go][sh];
+- Great for code generation: you can easily [prevent a task from running](usage.md#prevent-unnecessary-work)
+  if a given set of files haven't changed since last run (based either on its
+  timestamp or content).
+
+[make]: https://www.gnu.org/software/make/
+[go]: https://golang.org/
+[yaml]: http://yaml.org/
+[homebrew]: https://brew.sh/
+[snapcraft]: https://snapcraft.io/
+[scoop]: https://scoop.sh/
+[sh]: https://mvdan.cc/sh

docs/Taskfile.yml

@@ -0,0 +1,17 @@
+version: '3'
+
+tasks:
+  install:
+    desc: Installs docsify to work the on the documentation site
+    cmds:
+      - npm install docsify-cli -g
+
+  serve:
+    desc: Serves the documentation site locally
+    cmds:
+      - docsify serve .
+
+  ico:
+    desc: Generate favicon.ico from Logo.png
+    cmds:
+      - convert -background transparent "Logo.png" -define icon:auto-resize=16,24,32,48,64,72,96,128,256 "favicon.ico"

docs/_sidebar.md

@@ -0,0 +1,8 @@
+- [Installation](installation.md)
+- [Usage](usage.md)
+- [Styleguide](styleguide.md)
+- [Taskfile Versions](taskfile_versions.md)
+- [Examples](examples.md)
+- [Releasing Task](releasing_task.md)
+- [Donate](donate.md)
+- [![GitHub](https://icongram.jgog.in/simple/github.svg?color=808080&size=16)GitHub](https://github.com/go-task/task)

docs/donate.md

@@ -0,0 +1,35 @@
+# Donate
+
+If you find this project useful, you can consider donating by using one of the
+channels listed below.
+
+This is just a way of saying "thank you", it won't give you any benefits like
+higher priority on issues or something similar.
+
+## Open Collective
+
+Task is on [Open Collective](https://opencollective.com/task) and you have
+these options to donate:
+
+- [$2 per month](https://opencollective.com/task/contribute/backer-4034/checkout)
+- [$5 per month](https://opencollective.com/task/contribute/supporter-8404/checkout)
+- [$20 per month](https://opencollective.com/task/contribute/sponsor-4035/checkout)
+- [Custom value - One-time donation option supported](https://opencollective.com/task/donate)
+
+## Patreon
+
+I'm also on [Patreon](https://www.patreon.com/andreynering) if
+you prefer:
+
+- [$5 per month](https://www.patreon.com/join/andreynering/checkout?rid=4229277)
+- [$10 per month](https://www.patreon.com/join/andreynering/checkout?rid=4229276)
+- [$15 per month](https://www.patreon.com/join/andreynering/checkout?rid=4229275)
+
+You can choose a custom value on any of the links above.
+
+Patreon does not support one-time donation. As a workaround you can fire a
+subscription and cancel it once the donation was succeded.
+
+## PayPal
+
+- [Any value - One-time donation](https://www.paypal.com/cgi-bin/webscr?cmd=_donations&business=GSVDU63RKG45A&currency_code=BRL&source=url)

docs/examples.md

@@ -0,0 +1,7 @@
+# Examples
+
+The [go-task/examples][examples] intends to be a collection of Taskfiles for
+various use cases.
+(It still lacks many examples, though. Contributions are welcome).
+
+[examples]: https://github.com/go-task/examples

docs/index.html

@@ -0,0 +1,45 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8">
+    <title>Task</title>
+    <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1" />
+    <meta name="description" content="A task runner / simpler Make alternative written in Go">
+    <meta name="viewport" content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
+    <link rel="stylesheet" href="//cdn.jsdelivr.net/npm/docsify-themeable/dist/css/theme-simple.css">
+    <meta name="google-site-verification" content="VGAYkbdmuaciIDGkBe-eAg9yfZg0C6ostgonbGxxOa0" />
+    <style>
+      #logo {
+        transition: all 0.7s ease;
+      }
+      #logo:hover {
+        -webkit-transform: rotateZ(360deg);
+        -ms-transform: rotateZ(360deg);
+        transform: rotateZ(360deg);
+      }
+      .app-name-link img {
+        width: 125px;
+      }
+    </style>
+  </head>
+  <body>
+    <div id="app"></div>
+    <script>
+      window.$docsify = {
+        name: 'Task',
+        repo: 'go-task/task',
+        logo: 'Logo.png',
+        themeColor: '#29beb0',
+        loadSidebar: true,
+        auto2top: true,
+        maxLevel: 3,
+        subMaxLevel: 3
+      }
+    </script>
+    <script src="//cdn.jsdelivr.net/npm/docsify/lib/docsify.min.js"></script>
+    <script src="//cdn.jsdelivr.net/npm/docsify-themeable/dist/js/docsify-themeable.min.js"></script>
+    <script src="//cdn.jsdelivr.net/npm/docsify-tabs"></script>
+    <script src="//cdn.jsdelivr.net/npm/prismjs/components/prism-bash.min.js"></script>
+    <script src="//cdn.jsdelivr.net/npm/prismjs/components/prism-yaml.min.js"></script>
+  </body>
+</html>

docs/install.sh

@@ -0,0 +1,383 @@
+#!/bin/sh
+set -e
+# Code generated by godownloader on 2021-01-12T13:40:40Z. DO NOT EDIT.
+#
+
+usage() {
+  this=$1
+  cat <<EOF
+$this: download go binaries for go-task/task
+
+Usage: $this [-b] bindir [-d] [tag]
+  -b sets bindir or installation directory, Defaults to ./bin
+  -d turns on debug logging
+   [tag] is a tag from
+   https://github.com/go-task/task/releases
+   If tag is missing, then the latest will be used.
+
+ Generated by godownloader
+  https://github.com/goreleaser/godownloader
+
+EOF
+  exit 2
+}
+
+parse_args() {
+  #BINDIR is ./bin unless set be ENV
+  # over-ridden by flag below
+
+  BINDIR=${BINDIR:-./bin}
+  while getopts "b:dh?x" arg; do
+    case "$arg" in
+      b) BINDIR="$OPTARG" ;;
+      d) log_set_priority 10 ;;
+      h | \?) usage "$0" ;;
+      x) set -x ;;
+    esac
+  done
+  shift $((OPTIND - 1))
+  TAG=$1
+}
+# this function wraps all the destructive operations
+# if a curl|bash cuts off the end of the script due to
+# network, either nothing will happen or will syntax error
+# out preventing half-done work
+execute() {
+  tmpdir=$(mktemp -d)
+  log_debug "downloading files into ${tmpdir}"
+  http_download "${tmpdir}/${TARBALL}" "${TARBALL_URL}"
+  http_download "${tmpdir}/${CHECKSUM}" "${CHECKSUM_URL}"
+  hash_sha256_verify "${tmpdir}/${TARBALL}" "${tmpdir}/${CHECKSUM}"
+  srcdir="${tmpdir}"
+  (cd "${tmpdir}" && untar "${TARBALL}")
+  test ! -d "${BINDIR}" && install -d "${BINDIR}"
+  for binexe in $BINARIES; do
+    if [ "$OS" = "windows" ]; then
+      binexe="${binexe}.exe"
+    fi
+    install "${srcdir}/${binexe}" "${BINDIR}/"
+    log_info "installed ${BINDIR}/${binexe}"
+  done
+  rm -rf "${tmpdir}"
+}
+get_binaries() {
+  case "$PLATFORM" in
+    darwin/amd64) BINARIES="task" ;;
+    darwin/arm64) BINARIES="task" ;;
+    darwin/armv6) BINARIES="task" ;;
+    linux/386) BINARIES="task" ;;
+    linux/amd64) BINARIES="task" ;;
+    linux/arm64) BINARIES="task" ;;
+    linux/armv6) BINARIES="task" ;;
+    windows/386) BINARIES="task" ;;
+    windows/amd64) BINARIES="task" ;;
+    windows/arm64) BINARIES="task" ;;
+    windows/armv6) BINARIES="task" ;;
+    *)
+      log_crit "platform $PLATFORM is not supported.  Make sure this script is up-to-date and file request at https://github.com/${PREFIX}/issues/new"
+      exit 1
+      ;;
+  esac
+}
+tag_to_version() {
+  if [ -z "${TAG}" ]; then
+    log_info "checking GitHub for latest tag"
+  else
+    log_info "checking GitHub for tag '${TAG}'"
+  fi
+  REALTAG=$(github_release "$OWNER/$REPO" "${TAG}") && true
+  if test -z "$REALTAG"; then
+    log_crit "unable to find '${TAG}' - use 'latest' or see https://github.com/${PREFIX}/releases for details"
+    exit 1
+  fi
+  # if version starts with 'v', remove it
+  TAG="$REALTAG"
+  VERSION=${TAG#v}
+}
+adjust_format() {
+  # change format (tar.gz or zip) based on OS
+  case ${OS} in
+    windows) FORMAT=zip ;;
+  esac
+  true
+}
+adjust_os() {
+  # adjust archive name based on OS
+  true
+}
+adjust_arch() {
+  # adjust archive name based on ARCH
+  true
+}
+
+cat /dev/null <<EOF
+------------------------------------------------------------------------
+https://github.com/client9/shlib - portable posix shell functions
+Public domain - http://unlicense.org
+https://github.com/client9/shlib/blob/master/LICENSE.md
+but credit (and pull requests) appreciated.
+------------------------------------------------------------------------
+EOF
+is_command() {
+  command -v "$1" >/dev/null
+}
+echoerr() {
+  echo "$@" 1>&2
+}
+log_prefix() {
+  echo "$0"
+}
+_logp=6
+log_set_priority() {
+  _logp="$1"
+}
+log_priority() {
+  if test -z "$1"; then
+    echo "$_logp"
+    return
+  fi
+  [ "$1" -le "$_logp" ]
+}
+log_tag() {
+  case $1 in
+    0) echo "emerg" ;;
+    1) echo "alert" ;;
+    2) echo "crit" ;;
+    3) echo "err" ;;
+    4) echo "warning" ;;
+    5) echo "notice" ;;
+    6) echo "info" ;;
+    7) echo "debug" ;;
+    *) echo "$1" ;;
+  esac
+}
+log_debug() {
+  log_priority 7 || return 0
+  echoerr "$(log_prefix)" "$(log_tag 7)" "$@"
+}
+log_info() {
+  log_priority 6 || return 0
+  echoerr "$(log_prefix)" "$(log_tag 6)" "$@"
+}
+log_err() {
+  log_priority 3 || return 0
+  echoerr "$(log_prefix)" "$(log_tag 3)" "$@"
+}
+log_crit() {
+  log_priority 2 || return 0
+  echoerr "$(log_prefix)" "$(log_tag 2)" "$@"
+}
+uname_os() {
+  os=$(uname -s | tr '[:upper:]' '[:lower:]')
+  case "$os" in
+    cygwin_nt*) os="windows" ;;
+    mingw*) os="windows" ;;
+    msys_nt*) os="windows" ;;
+  esac
+  echo "$os"
+}
+uname_arch() {
+  arch=$(uname -m)
+  case $arch in
+    x86_64) arch="amd64" ;;
+    x86) arch="386" ;;
+    i686) arch="386" ;;
+    i386) arch="386" ;;
+    aarch64) arch="arm64" ;;
+    armv5*) arch="armv5" ;;
+    armv6*) arch="armv6" ;;
+    armv7*) arch="armv7" ;;
+  esac
+  echo ${arch}
+}
+uname_os_check() {
+  os=$(uname_os)
+  case "$os" in
+    darwin) return 0 ;;
+    dragonfly) return 0 ;;
+    freebsd) return 0 ;;
+    linux) return 0 ;;
+    android) return 0 ;;
+    nacl) return 0 ;;
+    netbsd) return 0 ;;
+    openbsd) return 0 ;;
+    plan9) return 0 ;;
+    solaris) return 0 ;;
+    windows) return 0 ;;
+  esac
+  log_crit "uname_os_check '$(uname -s)' got converted to '$os' which is not a GOOS value. Please file bug at https://github.com/client9/shlib"
+  return 1
+}
+uname_arch_check() {
+  arch=$(uname_arch)
+  case "$arch" in
+    386) return 0 ;;
+    amd64) return 0 ;;
+    arm64) return 0 ;;
+    armv5) return 0 ;;
+    armv6) return 0 ;;
+    armv7) return 0 ;;
+    ppc64) return 0 ;;
+    ppc64le) return 0 ;;
+    mips) return 0 ;;
+    mipsle) return 0 ;;
+    mips64) return 0 ;;
+    mips64le) return 0 ;;
+    s390x) return 0 ;;
+    amd64p32) return 0 ;;
+  esac
+  log_crit "uname_arch_check '$(uname -m)' got converted to '$arch' which is not a GOARCH value.  Please file bug report at https://github.com/client9/shlib"
+  return 1
+}
+untar() {
+  tarball=$1
+  case "${tarball}" in
+    *.tar.gz | *.tgz) tar --no-same-owner -xzf "${tarball}" ;;
+    *.tar) tar --no-same-owner -xf "${tarball}" ;;
+    *.zip) unzip "${tarball}" ;;
+    *)
+      log_err "untar unknown archive format for ${tarball}"
+      return 1
+      ;;
+  esac
+}
+http_download_curl() {
+  local_file=$1
+  source_url=$2
+  header=$3
+  if [ -z "$header" ]; then
+    code=$(curl -w '%{http_code}' -sL -o "$local_file" "$source_url")
+  else
+    code=$(curl -w '%{http_code}' -sL -H "$header" -o "$local_file" "$source_url")
+  fi
+  if [ "$code" != "200" ]; then
+    log_debug "http_download_curl received HTTP status $code"
+    return 1
+  fi
+  return 0
+}
+http_download_wget() {
+  local_file=$1
+  source_url=$2
+  header=$3
+  if [ -z "$header" ]; then
+    wget -q -O "$local_file" "$source_url"
+  else
+    wget -q --header "$header" -O "$local_file" "$source_url"
+  fi
+}
+http_download() {
+  log_debug "http_download $2"
+  if is_command curl; then
+    http_download_curl "$@"
+    return
+  elif is_command wget; then
+    http_download_wget "$@"
+    return
+  fi
+  log_crit "http_download unable to find wget or curl"
+  return 1
+}
+http_copy() {
+  tmp=$(mktemp)
+  http_download "${tmp}" "$1" "$2" || return 1
+  body=$(cat "$tmp")
+  rm -f "${tmp}"
+  echo "$body"
+}
+github_release() {
+  owner_repo=$1
+  version=$2
+  test -z "$version" && version="latest"
+  giturl="https://github.com/${owner_repo}/releases/${version}"
+  json=$(http_copy "$giturl" "Accept:application/json")
+  test -z "$json" && return 1
+  version=$(echo "$json" | tr -s '\n' ' ' | sed 's/.*"tag_name":"//' | sed 's/".*//')
+  test -z "$version" && return 1
+  echo "$version"
+}
+hash_sha256() {
+  TARGET=${1:-/dev/stdin}
+  if is_command gsha256sum; then
+    hash=$(gsha256sum "$TARGET") || return 1
+    echo "$hash" | cut -d ' ' -f 1
+  elif is_command sha256sum; then
+    hash=$(sha256sum "$TARGET") || return 1
+    echo "$hash" | cut -d ' ' -f 1
+  elif is_command shasum; then
+    hash=$(shasum -a 256 "$TARGET" 2>/dev/null) || return 1
+    echo "$hash" | cut -d ' ' -f 1
+  elif is_command openssl; then
+    hash=$(openssl -dst openssl dgst -sha256 "$TARGET") || return 1
+    echo "$hash" | cut -d ' ' -f a
+  else
+    log_crit "hash_sha256 unable to find command to compute sha-256 hash"
+    return 1
+  fi
+}
+hash_sha256_verify() {
+  TARGET=$1
+  checksums=$2
+  if [ -z "$checksums" ]; then
+    log_err "hash_sha256_verify checksum file not specified in arg2"
+    return 1
+  fi
+  BASENAME=${TARGET##*/}
+  want=$(grep "${BASENAME}" "${checksums}" 2>/dev/null | tr '\t' ' ' | cut -d ' ' -f 1)
+  if [ -z "$want" ]; then
+    log_err "hash_sha256_verify unable to find checksum for '${TARGET}' in '${checksums}'"
+    return 1
+  fi
+  got=$(hash_sha256 "$TARGET")
+  if [ "$want" != "$got" ]; then
+    log_err "hash_sha256_verify checksum for '$TARGET' did not verify ${want} vs $got"
+    return 1
+  fi
+}
+cat /dev/null <<EOF
+------------------------------------------------------------------------
+End of functions from https://github.com/client9/shlib
+------------------------------------------------------------------------
+EOF
+
+PROJECT_NAME="task"
+OWNER=go-task
+REPO="task"
+BINARY=task
+FORMAT=tar.gz
+OS=$(uname_os)
+ARCH=$(uname_arch)
+PREFIX="$OWNER/$REPO"
+
+# use in logging routines
+log_prefix() {
+	echo "$PREFIX"
+}
+PLATFORM="${OS}/${ARCH}"
+GITHUB_DOWNLOAD=https://github.com/${OWNER}/${REPO}/releases/download
+
+uname_os_check "$OS"
+uname_arch_check "$ARCH"
+
+parse_args "$@"
+
+get_binaries
+
+tag_to_version
+
+adjust_format
+
+adjust_os
+
+adjust_arch
+
+log_info "found version: ${VERSION} for ${TAG}/${OS}/${ARCH}"
+
+NAME=${BINARY}_${OS}_${ARCH}
+TARBALL=${NAME}.${FORMAT}
+TARBALL_URL=${GITHUB_DOWNLOAD}/${TAG}/${TARBALL}
+CHECKSUM=task_checksums.txt
+CHECKSUM_URL=${GITHUB_DOWNLOAD}/${TAG}/${CHECKSUM}
+
+
+execute

docs/installation.md

@@ -0,0 +1,142 @@
+# Installation
+
+Task offers many installation methods. Check out the available methods below.
+
+## Package Managers
+
+<!-- tabs:start -->
+
+#### **Homebrew**
+
+If you're on macOS or Linux and have [Homebrew][homebrew] installed, getting
+Task is as simple as running:
+
+```bash
+brew install go-task/tap/go-task
+```
+
+#### **Snap**
+
+Task is available in [Snapcraft][snapcraft], but keep in mind that your
+Linux distribution should allow classic confinement for Snaps to Task work
+right:
+
+```bash
+sudo snap install task --classic
+```
+
+#### **Scoop**
+
+If you're on Windows and have [Scoop][scoop] installed, use `extras` bucket
+to install Task like:
+
+```cmd
+scoop bucket add extras
+scoop install task
+```
+
+This installation method is community owned. After a new release of Task, it
+may take some time until it's available on Scoop.
+
+#### **AUR**
+
+If you're on Arch Linux you can install Task from
+[AUR](https://aur.archlinux.org/packages/taskfile-git) using your favorite
+package manager such as `yay`, `pacaur` or `yaourt`:
+
+```cmd
+yay -S taskfile-git
+```
+
+This installation method is community owned, but since it's `-git` version of
+the package, it's always latest available version based on the Git repository.
+
+<!-- tabs:end -->
+
+## Get The Binary
+
+<!-- tabs:start -->
+
+#### **Binary**
+
+You can download the binary from the [releases page on GitHub][releases] and
+add to your `$PATH`.
+
+DEB and RPM packages are also available.
+
+The `task_checksums.txt` file contains the SHA-256 checksum for each file.
+
+#### **Install Script**
+
+We also have a [install script][installscript], which is very useful on
+scenarios like CIs. Many thanks to [GoDownloader][godownloader] for allowing
+easily generating this script.
+
+```bash
+# For Default Installion to ./bin with debug logging
+sh -c "$(curl --location https://taskfile.dev/install.sh)" -- -d
+
+# For Installation To /usr/local/bin for userwide access with debug logging
+# May require sudo sh
+sh -c "$(curl --location https://taskfile.dev/install.sh)" -- -d -b /usr/local/bin
+
+```
+
+> This method will download the binary on the local `./bin` directory by default.
+
+#### **GitHub Actions**
+
+If you want to install Task in GitHub Actions you can try using
+[this action](https://github.com/arduino/actions/tree/master/setup-taskfile)
+by the Arduino team:
+
+```yaml
+- name: Install Task
+  uses: Arduino/actions/setup-taskfile@master
+```
+
+This installation method is community owned.
+
+<!-- tabs:end -->
+
+## Build From Source
+
+<!-- tabs:start -->
+
+#### **Go Modules**
+
+First, make sure you have [Go][go] properly installed and setup.
+
+You can easily install it globally by running:
+
+```bash
+go get -u github.com/go-task/task/v3/cmd/task
+```
+
+Or you can install into another directory:
+
+```bash
+git clone https://github.com/go-task/task
+cd task
+
+# Compiling binary to $GOPATH/bin
+go install -v ./cmd/task
+
+# Compiling it to another location.
+# Use -o ./task.exe on Windows.
+go build -v -o ./task ./cmd/task
+```
+
+> For CI environments we recommend using the [Install Script](#get-the-binary)
+> instead, which is faster and more stable, since it'll just download the latest
+> released binary, instead of compiling the edge (master branch) version.
+
+<!-- tabs:end -->
+
+[go]: https://golang.org/
+[snapcraft]: https://snapcraft.io/task
+[homebrew]: https://brew.sh/
+[installscript]: https://github.com/go-task/task/blob/master/install-task.sh
+[releases]: https://github.com/go-task/task/releases
+[godownloader]: https://github.com/goreleaser/godownloader
+[scoop]: https://scoop.sh/

docs/releasing_task.md

@@ -0,0 +1,39 @@
+# Releasing Task
+
+The release process of Task is done with the help of
+[GoReleaser][goreleaser]. You can test the release process locally by calling
+the `test-release` task of the Taskfile.
+
+[GitHub Actions](https://github.com/go-task/task/actions) should release
+artifacts automatically when a new Git tag is pushed to master
+(raw executables and DEB and RPM packages).
+
+# Homebrew
+
+To release a new version on the [Homebrew tap][homebrewtap] edit the
+[Formula/go-task.rb][gotaskrb] file, updating with the new version, download
+URL and sha256.
+
+# Snapcraft
+
+The exception is the publishing of a new version of the
+[snap package][snappackage]. This current require two steps after publishing
+the binaries:
+
+* Updating the current version on [snapcraft.yaml][snapcraftyaml];
+* Moving both `i386` and `amd64` new artifacts to the stable channel on
+the [Snapcraft dashboard][snapcraftdashboard]
+
+# Scoop
+
+Scoop is a community owned installation method. Scoop owners usually take care
+of updating versions there by editing
+[this file](https://github.com/lukesampson/scoop-extras/blob/master/bucket/task.json).
+If you think its Task version is outdated, open an issue to let us know.
+
+[goreleaser]: https://goreleaser.com/#continuous_integration
+[homebrewtap]: https://github.com/go-task/homebrew-tap
+[gotaskrb]: https://github.com/go-task/homebrew-tap/blob/master/Formula/go-task.rb
+[snappackage]: https://github.com/go-task/snap
+[snapcraftyaml]: https://github.com/go-task/snap/blob/master/snap/snapcraft.yaml#L2
+[snapcraftdashboard]: https://dashboard.snapcraft.io/

docs/styleguide.md

@@ -0,0 +1,213 @@
+# Styleguide
+
+This is the official Task styleguide for `Taskfile.yml` files. This guide
+contains some basic instructions to keep your Taskfile clean and familiar to
+other users.
+
+This contains general guidelines, but don't necessarely need to be strictly
+followed. Feel free to disagree and proceed differently in some point if you
+need or want to. Also, feel free to open issues or pull requests with
+improvements to this guide.
+
+## Use `Taskfile.yml` and not `taskfile.yml`
+
+```yaml
+# bad
+taskfile.yml
+
+
+# good
+Taskfile.yml
+```
+
+This is important especially for Linux users. Windows and macOS have case
+insensitive filesystems, so `taskfile.yml` will end up working, even that not
+officially supported. On Linux, only `Taskfile.yml` will work, though.
+
+## Use the correct order of keywords
+
+- `version:`
+- `includes:`
+- Configuration ones, like `output:`, `expansions:` or `silent:`
+- `vars:`
+- `env:`
+- `tasks:`
+
+## Use 2 spaces for indentation
+
+This is the most common convention for YAML files, and Task follows it.
+
+```yaml
+# bad
+tasks:
+    foo:
+        cmds:
+            - echo 'foo'
+
+
+# good
+tasks:
+  foo:
+    cmds:
+      - echo 'foo'
+```
+
+## Separate with spaces the mains sections
+
+```yaml
+# bad
+version: '3'
+includes:
+  docker: ./docker/Taskfile.yml
+output: prefixed
+expansions: 3
+vars:
+  FOO: bar
+env:
+  BAR: baz
+tasks:
+  # ...
+
+
+# good
+version: '3'
+
+includes:
+  docker: ./docker/Taskfile.yml
+
+output: prefixed
+expansions: 3
+
+vars:
+  FOO: bar
+
+env:
+  BAR: baz
+
+tasks:
+  # ...
+```
+
+## Add spaces between tasks
+
+```yaml
+# bad
+version: '3'
+
+tasks:
+  foo:
+    cmds:
+      - echo 'foo'
+  bar:
+    cmds:
+      - echo 'bar'
+  baz:
+    cmds:
+      - echo 'baz'
+
+
+# good
+version: '3'
+
+tasks:
+  foo:
+    cmds:
+      - echo 'foo'
+
+  bar:
+    cmds:
+      - echo 'bar'
+
+  baz:
+    cmds:
+      - echo 'baz'
+```
+
+## Use upper-case variable names
+
+```yaml
+# bad
+version: '3'
+
+vars:
+  binary_name: myapp
+
+tasks:
+  build:
+    cmds:
+      - go build -o {{.binary_name}} .
+
+
+# good
+version: '3'
+
+vars:
+  BINARY_NAME: myapp
+
+tasks:
+  build:
+    cmds:
+      - go build -o {{.BINARY_NAME}} .
+```
+
+## Don't wrap vars in spaces when templating
+
+```yaml
+# bad
+version: '3'
+
+tasks:
+  greet:
+    cmds:
+      - echo '{{ .MESSAGE }}'
+
+
+# good
+version: '3'
+
+tasks:
+  greet:
+    cmds:
+      - echo '{{.MESSAGE}}'
+```
+
+This convention is also used by most people for any Go templating.
+
+## Separate task name words with a dash
+
+```yaml
+# bad
+version: '3'
+
+tasks:
+  do_something_fancy:
+    cmds:
+      - echo 'Do something'
+
+
+# good
+version: '3'
+
+tasks:
+  do-something-fancy:
+    cmds:
+      - echo 'Do something'
+```
+
+## Use colon for task namespacing
+
+```yaml
+# good
+version: '3'
+
+tasks:
+  docker:build:
+    cmds:
+      - docker ...
+
+  docker:run:
+    cmds:
+      - docker-compose ...
+```
+
+This is also done automatically when using included Taskfiles.

docs/taskfile_versions.md

@@ -0,0 +1,225 @@
+# Taskfile Versions
+
+The Taskfile syntax and features changed with time. This document explains what
+changed on each version and how to upgrade your Taskfile.
+
+## What the Taskfile version mean
+
+The Taskfile version follows the Task version. E.g. the change to Taskfile
+version `2` means that Task `v2.0.0` should be release to support it.
+
+The `version:` key on Taskfile accepts a semver string, so either `2`, `2.0` or
+`2.0.0` is accepted. If you choose to use `2.0` Task will not enable future
+`2.1` features, but if you choose to use `2`, then any `2.x.x` features will be
+available, but not `3.0.0+`.
+
+## Version 1
+
+> NOTE: Taskfiles in version 1 are not supported on Task >= v3.0.0 anymore.
+
+In the first version of the `Taskfile`, the `version:` key was not available,
+because the tasks was in the root of the YAML document. Like this:
+
+```yaml
+echo:
+  cmds:
+    - echo "Hello, World!"
+```
+
+The variable priority order was also different:
+
+1. Call variables
+2. Environment
+3. Task variables
+4. `Taskvars.yml` variables
+
+## Version 2.0
+
+At version 2, we introduced the `version:` key, to allow us to evolve Task
+with new features without breaking existing Taskfiles. The new syntax is as
+follows:
+
+```yaml
+version: '2'
+
+tasks:
+  echo:
+    cmds:
+      - echo "Hello, World!"
+```
+
+Version 2 allows you to write global variables directly in the Taskfile,
+if you don't want to create a `Taskvars.yml`:
+
+```yaml
+version: '2'
+
+vars:
+  GREETING: Hello, World!
+
+tasks:
+  greet:
+    cmds:
+      - echo "{{.GREETING}}"
+```
+
+The variable priority order changed to the following:
+
+1. Task variables
+2. Call variables
+3. Taskfile variables
+4. Taskvars file variables
+5. Environment variables
+
+A new global option was added to configure the number of variables expansions
+(which default to 2):
+
+```yaml
+version: '2'
+
+expansions: 3
+
+vars:
+  FOO: foo
+  BAR: bar
+  BAZ: baz
+  FOOBAR: "{{.FOO}}{{.BAR}}"
+  FOOBARBAZ: "{{.FOOBAR}}{{.BAZ}}"
+
+tasks:
+  default:
+    cmds:
+      - echo "{{.FOOBARBAZ}}"
+```
+
+## Version 2.1
+
+Version 2.1 includes a global `output` option, to allow having more control
+over how commands output are printed to the console
+(see [documentation][output] for more info):
+
+```yaml
+version: '2'
+
+output: prefixed
+
+tasks:
+  server:
+    cmds:
+      - go run main.go
+  prefix: server
+```
+
+From this version it's also possible to ignore errors of a command or task
+(check documentation [here][ignore_errors]):
+
+```yaml
+version: '2'
+
+tasks:
+  example-1:
+    cmds:
+      - cmd: exit 1
+        ignore_error: true
+      - echo "This will be print"
+
+  example-2:
+    cmds:
+      - exit 1
+      - echo "This will be print"
+    ignore_error: true
+```
+
+## Version 2.2
+
+Version 2.2 comes with a global `includes` options to include other
+Taskfiles:
+
+```yaml
+version: '2'
+
+includes:
+  docs: ./documentation # will look for ./documentation/Taskfile.yml
+  docker: ./DockerTasks.yml
+```
+
+## Version 2.6
+
+Version 2.6 comes with `preconditions` stanza in tasks.
+
+```yaml
+version: '2'
+
+tasks:
+  upload_environment:
+    preconditions:
+      - test -f .env
+    cmds:
+      - aws s3 cp .env s3://myenvironment
+```
+
+Please check the [documentation][includes]
+
+[output]: usage.md#output-syntax
+[ignore_errors]: usage.md#ignore-errors
+[includes]: usage.md#including-other-taskfiles
+
+## Version 3
+
+These are some major changes done on `v3`:
+
+- Task's output will now be colored
+- Added support for `.env` like files
+- Added `label:` setting to task so one can override how the task name
+  appear in the logs
+- A global `method:` was added to allow setting the default method,
+  and Task's default changed to `checksum`
+- Two magic variables were added when using `status:`: `CHECKSUM` and
+  `TIMESTAMP` which contains, respectively, the md5 checksum and greatest
+  modification timestamp of the files listed on `sources:`
+- Also, the `TASK` variable is always available with the current task name
+- CLI variables are always treated as global variables
+- Added `dir:` option to `includes` to allow choosing on which directory an
+  included Taskfile will run:
+
+```yaml
+includes:
+  docs:
+    taskfile: ./docs
+    dir: ./docs
+```
+
+- Implemented short task syntax. All below syntaxes are equivalent:
+
+```yaml
+version: '3'
+
+tasks:
+  print:
+    cmds:
+      - echo "Hello, World!"
+```
+
+```yaml
+version: '3'
+
+tasks:
+  print:
+    - echo "Hello, World!"
+```
+
+```yaml
+version: '3'
+
+tasks:
+  print: echo "Hello, World!"
+```
+
+- There was a major refactor on how variables are handled. They're now easier
+  to understand. The `expansions:` setting was removed as it became unncessary.
+  This is the order in which Task will process variables, each level can see
+  the variables set by the previous one and override those.
+  - Environment variables
+  - Global + CLI variables
+  - Call variables
+  - Task variables

docs/usage.md

@@ -0,0 +1,909 @@
+# Usage
+
+## Getting started
+
+Create a file called `Taskfile.yml` in the root of your project.
+The `cmds` attribute should contain the commands of a task.
+The example below allows compiling a Go app and uses [Minify][minify] to concat
+and minify multiple CSS files into a single one.
+
+```yaml
+version: '3'
+
+tasks:
+  build:
+    cmds:
+      - go build -v -i main.go
+
+  assets:
+    cmds:
+      - minify -o public/style.css src/css
+```
+
+Running the tasks is as simple as running:
+
+```bash
+task assets build
+```
+
+Task uses [github.com/mvdan/sh](https://github.com/mvdan/sh), a native Go sh
+interpreter. So you can write sh/bash commands and it will work even on
+Windows, where `sh` or `bash` are usually not available. Just remember any
+executable called must be available by the OS or in PATH.
+
+If you omit a task name, "default" will be assumed.
+
+## Environment variables
+
+### Task
+
+You can use `env` to set custom environment variables for a specific task:
+
+```yaml
+version: '3'
+
+tasks:
+  greet:
+    cmds:
+      - echo $GREETING
+    env:
+      GREETING: Hey, there!
+```
+
+Additionally, you can set globally environment variables, that'll be available
+to all tasks:
+
+```yaml
+version: '3'
+
+env:
+  GREETING: Hey, there!
+
+tasks:
+  greet:
+    cmds:
+      - echo $GREETING
+```
+
+> NOTE: `env` supports expansion and retrieving output from a shell command
+> just like variables, as you can see on the [Variables](#variables) section.
+
+### .env files
+
+You can also ask Task to include `.env` like files by using the `dotenv:`
+setting:
+
+```
+# .env
+KEYNAME=VALUE
+```
+
+
+```yaml
+# Taskfile.yml
+
+version: '3'
+
+dotenv: ['.env']
+
+tasks:
+  greet:
+    cmds:
+      - echo "Using $KEYNAME"
+```
+
+## Including other Taskfiles
+
+If you want to share tasks between different projects (Taskfiles), you can use
+the importing mechanism to include other Taskfiles using the `includes` keyword:
+
+```yaml
+version: '3'
+
+includes:
+  docs: ./documentation # will look for ./documentation/Taskfile.yml
+  docker: ./DockerTasks.yml
+```
+
+The tasks described in the given Taskfiles will be available with the informed
+namespace. So, you'd call `task docs:serve` to run the `serve` task from
+`documentation/Taskfile.yml` or `task docker:build` to run the `build` task
+from the `DockerTasks.yml` file.
+
+### OS-specific Taskfiles
+
+With `version: '2'`, task automatically includes any `Taskfile_{{OS}}.yml`
+if it exists (for example: `Taskfile_windows.yml`, `Taskfile_linux.yml` or
+`Taskfile_darwin.yml`). Since this behavior was a bit too implicit, it
+was removed on version 3, but you still can have a similar behavior by
+explicitly importing these files:
+
+```yaml
+version: '3'
+
+includes:
+  build: ./Taskfile_{{OS}}.yml
+```
+
+### Directory of included Taskfile
+
+By default, included Taskfile's tasks are ran in the current directory, even
+if the Taskfile is in another directory, but you can force its tasks to run
+in another directory by using this alternative syntax:
+
+```yaml
+version: '3'
+
+includes:
+  docs:
+    taskfile: ./docs/Taskfile.yml
+    dir: ./docs
+```
+
+> The included Taskfiles must be using the same schema version the main
+> Taskfile uses.
+
+> Also, for now included Taskfiles can't include other Taskfiles.
+> This was a deliberate decision to keep use and implementation simple.
+> If you disagree, open an GitHub issue and explain your use case. =)
+
+## Task directory
+
+By default, tasks will be executed in the directory where the Taskfile is
+located. But you can easily make the task run in another folder informing
+`dir`:
+
+```yaml
+version: '3'
+
+tasks:
+  serve:
+    dir: public/www
+    cmds:
+      # run http server
+      - caddy
+```
+
+If the directory doesn't exist, `task` creates it.
+
+## Task dependencies
+
+> Dependencies run in parallel, so dependencies of a task shouldn't depend one
+> another. If you want to force tasks to run serially take a look at the
+> [Calling Another Task](#calling-another-task) section below.
+
+You may have tasks that depend on others. Just pointing them on `deps` will
+make them run automatically before running the parent task:
+
+```yaml
+version: '3'
+
+tasks:
+  build:
+    deps: [assets]
+    cmds:
+      - go build -v -i main.go
+
+  assets:
+    cmds:
+      - minify -o public/style.css src/css
+```
+
+In the above example, `assets` will always run right before `build` if you run
+`task build`.
+
+A task can have only dependencies and no commands to group tasks together:
+
+```yaml
+version: '3'
+
+tasks:
+  assets:
+    deps: [js, css]
+
+  js:
+    cmds:
+      - minify -o public/script.js src/js
+
+  css:
+    cmds:
+      - minify -o public/style.css src/css
+```
+
+If there is more than one dependency, they always run in parallel for better
+performance.
+
+> You can also make the tasks given by the command line run in parallel by
+> using the `--parallel` flag (alias `-p`). Example: `task --parallel js css`.
+
+If you want to pass information to dependencies, you can do that the same
+manner as you would to [call another task](#calling-another-task):
+
+```yaml
+version: '3'
+
+tasks:
+  default:
+    deps:
+      - task: echo_sth
+        vars: {TEXT: "before 1"}
+      - task: echo_sth
+        vars: {TEXT: "before 2"}
+    cmds:
+      - echo "after"
+
+  echo_sth:
+    cmds:
+      - echo {{.TEXT}}
+```
+
+## Calling another task
+
+When a task has many dependencies, they are executed concurrently. This will
+often result in a faster build pipeline. But in some situations you may need
+to call other tasks serially. In this case, just use the following syntax:
+
+```yaml
+version: '3'
+
+tasks:
+  main-task:
+    cmds:
+      - task: task-to-be-called
+      - task: another-task
+      - echo "Both done"
+
+  task-to-be-called:
+    cmds:
+      - echo "Task to be called"
+
+  another-task:
+    cmds:
+      - echo "Another task"
+```
+
+Overriding variables in the called task is as simple as informing `vars`
+attribute:
+
+```yaml
+version: '3'
+
+tasks:
+  greet:
+    vars:
+      RECIPIENT: '{{default "World" .RECIPIENT}}'
+    cmds:
+      - echo "Hello, {{.RECIPIENT}}!"
+
+  greet-pessimistically:
+    cmds:
+      - task: greet
+        vars: {RECIPIENT: "Cruel World"}
+```
+
+The above syntax is also supported in `deps`.
+
+> NOTE: If you want to call a task declared in the root Taskfile from within an
+> [included Taskfile](#including-other-taskfiles), add a leading `:` like this:
+> `task: :task-name`.
+
+## Prevent unnecessary work
+
+### By fingerprinting locally generated files and their sources
+
+If a task generates something, you can inform Task the source and generated
+files, so Task will prevent to run them if not necessary.
+
+```yaml
+version: '3'
+
+tasks:
+  build:
+    deps: [js, css]
+    cmds:
+      - go build -v -i main.go
+
+  js:
+    cmds:
+      - minify -o public/script.js src/js
+    sources:
+      - src/js/**/*.js
+    generates:
+      - public/script.js
+
+  css:
+    cmds:
+      - minify -o public/style.css src/css
+    sources:
+      - src/css/**/*.css
+    generates:
+      - public/style.css
+```
+
+`sources` and `generates` can be files or file patterns. When given,
+Task will compare the checksum of the source files to determine if it's
+necessary to run the task. If not, it will just print a message like
+`Task "js" is up to date`.
+You will probably want to ignore the `.task` folder in your `.gitignore` file
+(It's there that Task stores the last checksum).
+
+If you prefer this check to be made by the modification timestamp of the files,
+instead of its checksum (content), just set the `method` property to `timestamp`.
+
+```yaml
+version: '3'
+
+tasks:
+  build:
+    cmds:
+      - go build .
+    sources:
+      - ./*.go
+    generates:
+      - app{{exeExt}}
+    method: checksum
+```
+
+> TIP: method `none` skips any validation and always run the task.
+
+> NOTE: for the `checksum` (default) method to work, it's only necessary to
+> inform the source files, but if you want to use the `timestamp` method, you
+> also need to inform the generated files with `generates`.
+
+### Using programmatic checks to indicate a task is up to date.
+
+Alternatively, you can inform a sequence of tests as `status`. If no error
+is returned (exit status 0), the task is considered up-to-date:
+
+```yaml
+version: '3'
+
+tasks:
+  generate-files:
+    cmds:
+      - mkdir directory
+      - touch directory/file1.txt
+      - touch directory/file2.txt
+    # test existence of files
+    status:
+      - test -d directory
+      - test -f directory/file1.txt
+      - test -f directory/file2.txt
+```
+
+Normally, you would use `sources` in combination with
+`generates` - but for tasks that generate remote artifacts (Docker images,
+deploys, CD releases) the checksum source and timestamps require either
+access to the artifact or for an out-of-band refresh of the `.checksum`
+fingerprint file.
+
+Two special variables `{{.CHECKSUM}}` and `{{.TIMESTAMP}}` are available
+for interpolation within `status` commands, depending on the method assigned
+to fingerprint the sources. Only `source` globs are fingerprinted.
+
+Note that the `{{.TIMESTAMP}}` variable is a "live" Go `time.Time` struct, and
+can be formatted using any of the methods that `time.Time` responds to.
+
+See [the Go Time documentation](https://golang.org/pkg/time/) for more information.
+
+You can use `--force` or `-f` if you want to force a task to run even when
+up-to-date.
+
+Also, `task --status [tasks]...` will exit with a non-zero exit code if any of
+the tasks are not up-to-date.
+
+### Using programmatic checks to cancel execution of an task and it's dependencies
+
+In addition to `status` checks, there are also `preconditions` checks, which are
+the logical inverse of `status` checks.  That is, if you need a certain set of
+conditions to be _true_ you can use the `preconditions` stanza.
+`preconditions` are similar to `status` lines except they support `sh`
+expansion and they SHOULD all return 0.
+
+```yaml
+version: '3'
+
+tasks:
+  generate-files:
+    cmds:
+      - mkdir directory
+      - touch directory/file1.txt
+      - touch directory/file2.txt
+    # test existence of files
+    preconditions:
+      - test -f .env
+      - sh: "[ 1 = 0 ]"
+        msg: "One doesn't equal Zero, Halting"
+```
+
+Preconditions can set specific failure messages that can tell
+a user what steps to take using the `msg` field.
+
+If a task has a dependency on a sub-task with a precondition, and that
+precondition is not met - the calling task will fail.  Note that a task
+executed with a failing precondition will not run unless `--force` is
+given.
+
+Unlike `status` which will skip a task if it is up to date, and continue
+executing tasks that depend on it, a `precondition` will fail a task, along
+with any other tasks that depend on it.
+
+```yaml
+version: '3'
+
+tasks:
+  task-will-fail:
+    preconditions:
+      - sh: "exit 1"
+
+  task-will-also-fail:
+    deps:
+      - task-will-fail
+
+  task-will-still-fail:
+    cmds:
+      - task: task-will-fail
+      - echo "I will not run"
+```
+
+## Variables
+
+When doing interpolation of variables, Task will look for the below.
+They are listed below in order of importance (e.g. most important first):
+
+- Variables declared in the task definition
+- Variables given while calling a task from another
+  (See [Calling another task](#calling-another-task) above)
+- Global variables (those declared in the `vars:` option in the Taskfile)
+- Environment variables
+
+Example of sending parameters with environment variables:
+
+```bash
+$ TASK_VARIABLE=a-value task do-something
+```
+
+> TIP: A special variable `.TASK` is always available containing the task name.
+
+Since some shells don't support above syntax to set environment variables
+(Windows) tasks also accepts a similar style when not in the beginning of
+the command.
+
+```bash
+$ task write-file FILE=file.txt "CONTENT=Hello, World!" print "MESSAGE=All done!"
+```
+
+Example of locally declared vars:
+
+```yaml
+version: '3'
+
+tasks:
+  print-var:
+    cmds:
+      - echo "{{.VAR}}"
+    vars:
+      VAR: Hello!
+```
+
+Example of global vars in a `Taskfile.yml`:
+
+```yaml
+version: '3'
+
+vars:
+  GREETING: Hello from Taskfile!
+
+tasks:
+  greet:
+    cmds:
+      - echo "{{.GREETING}}"
+```
+
+### Dynamic variables
+
+The below syntax (`sh:` prop in a variable) is considered a dynamic variable.
+The value will be treated as a command and the output assigned. If there is one
+or more trailing newlines, the last newline will be trimmed.
+
+```yaml
+version: '3'
+
+tasks:
+  build:
+    cmds:
+      - go build -ldflags="-X main.Version={{.GIT_COMMIT}}" main.go
+    vars:
+      GIT_COMMIT:
+        sh: git log -n 1 --format=%h
+```
+
+This works for all types of variables.
+
+## Forwarding CLI arguments to commands
+
+If `--` is given in the CLI, all following paramaters are added to a
+special `.CLI_ARGS` variable. This is useful to forward arguments to another
+command.
+
+The below example will run `yarn install`.
+
+```bash
+$ task yarn -- install
+```
+
+```yaml
+version: '3'
+
+tasks:
+  yarn:
+    cmds:
+      - yarn {{.CLI_ARGS}}
+```
+
+## Go's template engine
+
+Task parse commands as [Go's template engine][gotemplate] before executing
+them. Variables are accessible through dot syntax (`.VARNAME`).
+
+All functions by the Go's [slim-sprig lib](https://go-task.github.io/slim-sprig/)
+are available. The following example gets the current date in a given format:
+
+```yaml
+version: '3'
+
+tasks:
+  print-date:
+    cmds:
+      - echo {{now | date "2006-01-02"}}
+```
+
+Task also adds the following functions:
+
+- `OS`: Returns operating system. Possible values are "windows", "linux",
+  "darwin" (macOS) and "freebsd".
+- `ARCH`: return the architecture Task was compiled to: "386", "amd64", "arm"
+  or "s390x".
+- `splitLines`: Splits Unix (\n) and Windows (\r\n) styled newlines.
+- `catLines`: Replaces Unix (\n) and Windows (\r\n) styled newlines with a space.
+- `toSlash`: Does nothing on Unix, but on Windows converts a string from `\`
+  path format to `/`.
+- `fromSlash`: Opposite of `toSlash`. Does nothing on Unix, but on Windows
+  converts a string from `\` path format to `/`.
+- `exeExt`: Returns the right executable extension for the current OS
+  (`".exe"` for Windows, `""` for others).
+
+Example:
+
+```yaml
+version: '3'
+
+tasks:
+  print-os:
+    cmds:
+      - echo '{{OS}} {{ARCH}}'
+      - echo '{{if eq OS "windows"}}windows-command{{else}}unix-command{{end}}'
+      # This will be path/to/file on Unix but path\to\file on Windows
+      - echo '{{fromSlash "path/to/file"}}'
+  enumerated-file:
+    vars:
+      CONTENT: |
+        foo
+        bar
+    cmds:
+      - |
+        cat << EOF > output.txt
+        {{range $i, $line := .CONTENT | splitLines -}}
+        {{printf "%3d" $i}}: {{$line}}
+        {{end}}EOF
+```
+
+## Help
+
+Running `task --list` (or `task -l`) lists all tasks with a description.
+The following Taskfile:
+
+```yaml
+version: '3'
+
+tasks:
+  build:
+    desc: Build the go binary.
+    cmds:
+      - go build -v -i main.go
+
+  test:
+    desc: Run all the go tests.
+    cmds:
+      - go test -race ./...
+
+  js:
+    cmds:
+      - minify -o public/script.js src/js
+
+  css:
+    cmds:
+      - minify -o public/style.css src/css
+```
+
+would print the following output:
+
+```bash
+* build:   Build the go binary.
+* test:    Run all the go tests.
+```
+
+## Display summary of task
+
+Running `task --summary task-name` will show a summary of a task.
+The following Taskfile:
+
+```yaml
+version: '3'
+
+tasks:
+  release:
+    deps: [build]
+    summary: |
+      Release your project to github
+
+      It will build your project before starting the release.
+      Please make sure that you have set GITHUB_TOKEN before starting.
+    cmds:
+      - your-release-tool
+
+  build:
+    cmds:
+      - your-build-tool
+```
+
+with running ``task --summary release`` would print the following output:
+
+```
+task: release
+
+Release your project to github
+
+It will build your project before starting the release.
+Please make sure that you have set GITHUB_TOKEN before starting.
+
+dependencies:
+ - build
+
+commands:
+ - your-release-tool
+```
+If a summary is missing, the description will be printed.
+If the task does not have a summary or a description, a warning is printed.
+
+Please note: *showing the summary will not execute the command*.
+
+## Overriding task name
+
+Sometimes you may want to override the task name print on summary, up-to-date
+messages to STDOUT, etc. In this case you can just set `label:`, which can also
+be interpolated with variables:
+
+```yaml
+version: '3'
+
+tasks:
+  default:
+    - task: print
+      vars:
+        MESSAGE: hello
+    - task: print
+      vars:
+        MESSAGE: world
+
+  print:
+    label: 'print-{{.MESSAGE}}'
+    cmds:
+      - echo "{{.MESSAGE}}"
+```
+
+## Silent mode
+
+Silent mode disables echoing of commands before Task runs it.
+For the following Taskfile:
+
+```yaml
+version: '3'
+
+tasks:
+  echo:
+    cmds:
+      - echo "Print something"
+```
+
+Normally this will be print:
+
+```sh
+echo "Print something"
+Print something
+```
+
+With silent mode on, the below will be print instead:
+
+```sh
+Print something
+```
+
+There are four ways to enable silent mode:
+
+* At command level:
+
+```yaml
+version: '3'
+
+tasks:
+  echo:
+    cmds:
+      - cmd: echo "Print something"
+        silent: true
+```
+
+* At task level:
+
+```yaml
+version: '3'
+
+tasks:
+  echo:
+    cmds:
+      - echo "Print something"
+    silent: true
+```
+
+* Globally at Taskfile level:
+
+```yaml
+version: '3'
+
+silent: true
+
+tasks:
+  echo:
+    cmds:
+      - echo "Print something"
+```
+
+* Or globally with `--silent` or `-s` flag
+
+If you want to suppress STDOUT instead, just redirect a command to `/dev/null`:
+
+```yaml
+version: '3'
+
+tasks:
+  echo:
+    cmds:
+      - echo "This will print nothing" > /dev/null
+```
+
+## Dry run mode
+
+Dry run mode (`--dry`) compiles and steps through each task, printing the commands
+that would be run without executing them. This is useful for debugging your Taskfiles.
+
+## Ignore errors
+
+You have the option to ignore errors during command execution.
+Given the following Taskfile:
+
+```yaml
+version: '3'
+
+tasks:
+  echo:
+    cmds:
+      - exit 1
+      - echo "Hello World"
+```
+
+Task will abort the execution after running `exit 1` because the status code `1` stands for `EXIT_FAILURE`.
+However it is possible to continue with execution using `ignore_error`:
+
+```yaml
+version: '3'
+
+tasks:
+  echo:
+    cmds:
+      - cmd: exit 1
+        ignore_error: true
+      - echo "Hello World"
+```
+
+`ignore_error` can also be set for a task, which mean errors will be suppressed
+for all commands. But keep in mind this option won't propagate to other tasks
+called either by `deps` or `cmds`!
+
+## Output syntax
+
+By default, Task just redirect the STDOUT and STDERR of the running commands
+to the shell in real time. This is good for having live feedback for log
+printed by commands, but the output can become messy if you have multiple
+commands running at the same time and printing lots of stuff.
+
+To make this more customizable, there are currently three different output
+options you can choose:
+
+- `interleaved` (default)
+- `group`
+- `prefixed`
+
+To choose another one, just set it to root in the Taskfile:
+
+```yaml
+version: '3'
+
+output: 'group'
+
+tasks:
+  # ...
+```
+
+ The `group` output will print the entire output of a command once, after it
+ finishes, so you won't have live feedback for commands that take a long time
+ to run.
+
+ The `prefix` output will prefix every line printed by a command with
+ `[task-name] ` as the prefix, but you can customize the prefix for a command
+ with the `prefix:` attribute:
+
+ ```yaml
+version: '3'
+
+output: prefixed
+
+tasks:
+  default:
+    deps:
+      - task: print
+        vars: {TEXT: foo}
+      - task: print
+        vars: {TEXT: bar}
+      - task: print
+        vars: {TEXT: baz}
+
+  print:
+    cmds:
+      - echo "{{.TEXT}}"
+    prefix: "print-{{.TEXT}}"
+    silent: true
+```
+
+```bash
+$ task default
+[print-foo] foo
+[print-bar] bar
+[print-baz] baz
+```
+
+> The `output` option can also be specified by the `--output` or `-o` flags.
+
+## Short task syntax
+
+Starting on Task v3, you can now write tasks with a shorter syntax if they
+have the default settings (e.g. no custom `env:`, `vars:`, `desc:`, `silent:` , etc):
+
+```yaml
+version: '3'
+
+tasks:
+  build: go build -v -o ./app{{exeExt}} .
+
+  run:
+    - task: build
+    - ./app{{exeExt}} -h localhost -p 8080
+```
+
+## Watch tasks
+
+With the flags `--watch` or `-w` task will watch for file changes
+and run the task again. This requires the `sources` attribute to be given,
+so task knows which files to watch.
+
+[gotemplate]: https://golang.org/pkg/text/template/
+[minify]: https://github.com/tdewolff/minify/tree/master/cmd/minify

errors.go

@@ -0,0 +1,43 @@
+package task
+
+import (
+	"errors"
+	"fmt"
+)
+
+var (
+	// ErrTaskfileAlreadyExists is returned on creating a Taskfile if one already exists
+	ErrTaskfileAlreadyExists = errors.New("task: A Taskfile already exists")
+)
+
+type taskNotFoundError struct {
+	taskName string
+}
+
+func (err *taskNotFoundError) Error() string {
+	return fmt.Sprintf(`task: Task "%s" not found`, err.taskName)
+}
+
+type taskRunError struct {
+	taskName string
+	err      error
+}
+
+func (err *taskRunError) Error() string {
+	return fmt.Sprintf(`task: Failed to run task "%s": %v`, err.taskName, err.err)
+}
+
+// MaximumTaskCallExceededError is returned when a task is called too
+// many times. In this case you probably have a cyclic dependendy or
+// infinite loop
+type MaximumTaskCallExceededError struct {
+	task string
+}
+
+func (e *MaximumTaskCallExceededError) Error() string {
+	return fmt.Sprintf(
+		`task: maximum task call exceeded (%d) for task "%s": probably an cyclic dep or infinite loop`,
+		MaximumTaskCall,
+		e.task,
+	)
+}

file.go

@@ -1,87 +0,0 @@
-package task
-
-import (
-	"os"
-	"time"
-
-	"github.com/mattn/go-zglob"
-)
-
-var dirsToSkip = []string{
-	".git",
-	"node_modules",
-}
-
-func minTime(a, b time.Time) time.Time {
-	if !a.IsZero() && a.Before(b) {
-		return a
-	}
-	return b
-}
-func maxTime(a, b time.Time) time.Time {
-	if a.After(b) {
-		return a
-	}
-	return b
-}
-
-func getPatternsMinTime(patterns []string) (m time.Time, err error) {
-	for _, p := range patterns {
-		mp, err := getPatternMinTime(p)
-		if err != nil {
-			return time.Time{}, err
-		}
-		m = minTime(m, mp)
-	}
-	return
-}
-func getPatternsMaxTime(patterns []string) (m time.Time, err error) {
-	for _, p := range patterns {
-		mp, err := getPatternMaxTime(p)
-		if err != nil {
-			return time.Time{}, err
-		}
-		m = maxTime(m, mp)
-	}
-	return
-}
-
-func getPatternMinTime(pattern string) (minTime time.Time, err error) {
-	files, err := zglob.Glob(pattern)
-	if err != nil {
-		return time.Time{}, err
-	}
-
-	for _, f := range files {
-		info, err := os.Stat(f)
-		if err != nil {
-			return time.Time{}, err
-		}
-
-		modTime := info.ModTime()
-		if minTime.IsZero() || modTime.Before(minTime) {
-			minTime = modTime
-		}
-	}
-	return
-}
-
-func getPatternMaxTime(pattern string) (maxTime time.Time, err error) {
-	files, err := zglob.Glob(pattern)
-	if err != nil {
-		return time.Time{}, err
-	}
-
-	for _, f := range files {
-		info, err := os.Stat(f)
-		if err != nil {
-			return time.Time{}, err
-		}
-
-		modTime := info.ModTime()
-		if modTime.After(maxTime) {
-			maxTime = modTime
-		}
-	}
-	return
-}

go.mod

@@ -0,0 +1,17 @@
+module github.com/go-task/task/v3
+
+require (
+	github.com/fatih/color v1.7.0
+	github.com/go-task/slim-sprig v0.0.0-20210107165309-348f09dbbbc0
+	github.com/joho/godotenv v1.3.0
+	github.com/mattn/go-colorable v0.1.2 // indirect
+	github.com/mattn/go-zglob v0.0.1
+	github.com/radovskyb/watcher v1.0.5
+	github.com/spf13/pflag v1.0.5
+	github.com/stretchr/testify v1.5.1
+	golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9
+	gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c
+	mvdan.cc/sh/v3 v3.2.4
+)
+
+go 1.13

go.sum

@@ -0,0 +1,59 @@
+github.com/creack/pty v1.1.11 h1:07n33Z8lZxZ2qwegKbObQohDhXDQxiMMz1NOUGYlesw=
+github.com/creack/pty v1.1.11/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/fatih/color v1.7.0 h1:DkWD4oS2D8LGGgTQ6IvwJJXSL5Vp2ffcQg58nFV38Ys=
+github.com/fatih/color v1.7.0/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5KwzbycvMj4=
+github.com/go-task/slim-sprig v0.0.0-20210107165309-348f09dbbbc0 h1:p104kn46Q8WdvHunIJ9dAyjPVtrBPhSr3KT2yUst43I=
+github.com/go-task/slim-sprig v0.0.0-20210107165309-348f09dbbbc0/go.mod h1:fyg7847qk6SyHyPtNmDHnmrv/HOrqktSC+C9fM+CJOE=
+github.com/google/renameio v0.1.0/go.mod h1:KWCgfxg9yswjAJkECMjeO8J8rahYeXnNhOm40UhjYkI=
+github.com/joho/godotenv v1.3.0 h1:Zjp+RcGpHhGlrMbJzXTrZZPrWj+1vfm90La1wgB6Bhc=
+github.com/joho/godotenv v1.3.0/go.mod h1:7hK45KPybAkOC6peb+G5yklZfMxEjkZhHbwpqxOKXbg=
+github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
+github.com/kr/pretty v0.2.1 h1:Fmg33tUaq4/8ym9TJN1x7sLJnHVwhP33CNkpYV/7rwI=
+github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
+github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
+github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
+github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
+github.com/mattn/go-colorable v0.1.2 h1:/bC9yWikZXAL9uJdulbSfyVNIR3n3trXl+v8+1sx8mU=
+github.com/mattn/go-colorable v0.1.2/go.mod h1:U0ppj6V5qS13XJ6of8GYAs25YV2eR4EVcfRqFIhoBtE=
+github.com/mattn/go-isatty v0.0.8 h1:HLtExJ+uU2HOZ+wI0Tt5DtUDrx8yhUqDcp7fYERX4CE=
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+github.com/mattn/go-zglob v0.0.1 h1:xsEx/XUoVlI6yXjqBK062zYhRTZltCNmYPx6v+8DNaY=
+github.com/mattn/go-zglob v0.0.1/go.mod h1:9fxibJccNxU2cnpIKLRRFA7zX7qhkJIQWBb449FYHOo=
+github.com/pkg/diff v0.0.0-20200914180035-5b29258ca4f7/go.mod h1:zO8QMzTeZd5cpnIkz/Gn6iK0jDfGicM1nynOkkPIl28=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
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+github.com/radovskyb/watcher v1.0.5 h1:wqt7gb+HjGacvFoLTKeT44C+XVPxu7bvHvKT1IvZ7rw=
+github.com/radovskyb/watcher v1.0.5/go.mod h1:78okwvY5wPdzcb1UYnip1pvrZNIVEIh/Cm+ZuvsUYIg=
+github.com/rogpeppe/go-internal v1.6.2/go.mod h1:xXDCJY+GAPziupqXw64V24skbSoqbTEfhy4qGm1nDQc=
+github.com/sergi/go-diff v1.0.0/go.mod h1:0CfEIISq7TuYL3j771MWULgwwjU+GofnZX9QAmXWZgo=
+github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
+github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
+github.com/stretchr/testify v1.5.1 h1:nOGnQDM7FYENwehXlg/kFVnos3rEvtKTjRvOWSzb6H4=
+github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
+golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9 h1:SQFwaSi55rU7vdNs9Yr0Z324VNlrF+0wMqRXT4St8ck=
+golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sys v0.0.0-20190222072716-a9d3bda3a223/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20191026070338-33540a1f6037/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20201029080932-201ba4db2418 h1:HlFl4V6pEMziuLXyRkm5BIYq1y1GAbb02pRlWvI54OM=
+golang.org/x/sys v0.0.0-20201029080932-201ba4db2418/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/term v0.0.0-20191110171634-ad39bd3f0407 h1:5zh5atpUEdIc478E/ebrIaHLKcfVvG6dL/fGv7BcMoM=
+golang.org/x/term v0.0.0-20191110171634-ad39bd3f0407/go.mod h1:Nr5EML6q2oocZ2LXRh80K7BxOlk5/8JxuGnuhpl+muw=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 h1:qIbj1fsPNlZgppZ+VLlY7N33q108Sa+fhmuc+sWQYwY=
+gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/errgo.v2 v2.1.0/go.mod h1:hNsd1EY+bozCKY1Ytp96fpM3vjJbqLJn88ws8XvfDNI=
+gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
+gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+mvdan.cc/editorconfig v0.1.1-0.20200121172147-e40951bde157/go.mod h1:Ge4atmRUYqueGppvJ7JNrtqpqokoJEFxYbP0Z+WeKS8=
+mvdan.cc/sh/v3 v3.2.4 h1:+fZaWcXWRjYAvqzEKoDhDM3DkxdDUykU2iw0VMKFe9s=
+mvdan.cc/sh/v3 v3.2.4/go.mod h1:fPQmabBpREM/XQ9YXSU5ZFZ/Sm+PmKP9/vkFHgYKJEI=

help.go

@@ -0,0 +1,42 @@
+package task
+
+import (
+	"fmt"
+	"sort"
+	"text/tabwriter"
+
+	"github.com/go-task/task/v3/internal/logger"
+	"github.com/go-task/task/v3/taskfile"
+)
+
+// PrintTasksHelp prints help os tasks that have a description
+func (e *Executor) PrintTasksHelp() {
+	tasks := e.tasksWithDesc()
+	if len(tasks) == 0 {
+		e.Logger.Outf(logger.Yellow, "task: No tasks with description available")
+		return
+	}
+	e.Logger.Outf(logger.Default, "task: Available tasks for this project:")
+
+	// Format in tab-separated columns with a tab stop of 8.
+	w := tabwriter.NewWriter(e.Stdout, 0, 8, 0, '\t', 0)
+	for _, task := range tasks {
+		fmt.Fprintf(w, "* %s: \t%s\n", task.Name(), task.Desc)
+	}
+	w.Flush()
+}
+
+func (e *Executor) tasksWithDesc() (tasks []*taskfile.Task) {
+	tasks = make([]*taskfile.Task, 0, len(e.Taskfile.Tasks))
+	for _, task := range e.Taskfile.Tasks {
+		if task.Desc != "" {
+			compiledTask, err := e.FastCompiledTask(taskfile.Call{Task: task.Task})
+			if err == nil {
+				task = compiledTask
+			}
+			tasks = append(tasks, task)
+		}
+	}
+	sort.Slice(tasks, func(i, j int) bool { return tasks[i].Task < tasks[j].Task })
+	return
+}

init.go

@@ -0,0 +1,38 @@
+package task
+
+import (
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+)
+
+const defaultTaskfile = `# https://taskfile.dev
+
+version: '3'
+
+vars:
+  GREETING: Hello, World!
+
+tasks:
+  default:
+    cmds:
+      - echo "{{.GREETING}}"
+    silent: true
+`
+
+// InitTaskfile Taskfile creates a new Taskfile
+func InitTaskfile(w io.Writer, dir string) error {
+	f := filepath.Join(dir, "Taskfile.yml")
+
+	if _, err := os.Stat(f); err == nil {
+		return ErrTaskfileAlreadyExists
+	}
+
+	if err := ioutil.WriteFile(f, []byte(defaultTaskfile), 0644); err != nil {
+		return err
+	}
+	fmt.Fprintf(w, "Taskfile.yml created in the current directory\n")
+	return nil
+}

install-task.sh

@@ -0,0 +1,383 @@
+#!/bin/sh
+set -e
+# Code generated by godownloader on 2021-01-12T13:40:40Z. DO NOT EDIT.
+#
+
+usage() {
+  this=$1
+  cat <<EOF
+$this: download go binaries for go-task/task
+
+Usage: $this [-b] bindir [-d] [tag]
+  -b sets bindir or installation directory, Defaults to ./bin
+  -d turns on debug logging
+   [tag] is a tag from
+   https://github.com/go-task/task/releases
+   If tag is missing, then the latest will be used.
+
+ Generated by godownloader
+  https://github.com/goreleaser/godownloader
+
+EOF
+  exit 2
+}
+
+parse_args() {
+  #BINDIR is ./bin unless set be ENV
+  # over-ridden by flag below
+
+  BINDIR=${BINDIR:-./bin}
+  while getopts "b:dh?x" arg; do
+    case "$arg" in
+      b) BINDIR="$OPTARG" ;;
+      d) log_set_priority 10 ;;
+      h | \?) usage "$0" ;;
+      x) set -x ;;
+    esac
+  done
+  shift $((OPTIND - 1))
+  TAG=$1
+}
+# this function wraps all the destructive operations
+# if a curl|bash cuts off the end of the script due to
+# network, either nothing will happen or will syntax error
+# out preventing half-done work
+execute() {
+  tmpdir=$(mktemp -d)
+  log_debug "downloading files into ${tmpdir}"
+  http_download "${tmpdir}/${TARBALL}" "${TARBALL_URL}"
+  http_download "${tmpdir}/${CHECKSUM}" "${CHECKSUM_URL}"
+  hash_sha256_verify "${tmpdir}/${TARBALL}" "${tmpdir}/${CHECKSUM}"
+  srcdir="${tmpdir}"
+  (cd "${tmpdir}" && untar "${TARBALL}")
+  test ! -d "${BINDIR}" && install -d "${BINDIR}"
+  for binexe in $BINARIES; do
+    if [ "$OS" = "windows" ]; then
+      binexe="${binexe}.exe"
+    fi
+    install "${srcdir}/${binexe}" "${BINDIR}/"
+    log_info "installed ${BINDIR}/${binexe}"
+  done
+  rm -rf "${tmpdir}"
+}
+get_binaries() {
+  case "$PLATFORM" in
+    darwin/amd64) BINARIES="task" ;;
+    darwin/arm64) BINARIES="task" ;;
+    darwin/armv6) BINARIES="task" ;;
+    linux/386) BINARIES="task" ;;
+    linux/amd64) BINARIES="task" ;;
+    linux/arm64) BINARIES="task" ;;
+    linux/armv6) BINARIES="task" ;;
+    windows/386) BINARIES="task" ;;
+    windows/amd64) BINARIES="task" ;;
+    windows/arm64) BINARIES="task" ;;
+    windows/armv6) BINARIES="task" ;;
+    *)
+      log_crit "platform $PLATFORM is not supported.  Make sure this script is up-to-date and file request at https://github.com/${PREFIX}/issues/new"
+      exit 1
+      ;;
+  esac
+}
+tag_to_version() {
+  if [ -z "${TAG}" ]; then
+    log_info "checking GitHub for latest tag"
+  else
+    log_info "checking GitHub for tag '${TAG}'"
+  fi
+  REALTAG=$(github_release "$OWNER/$REPO" "${TAG}") && true
+  if test -z "$REALTAG"; then
+    log_crit "unable to find '${TAG}' - use 'latest' or see https://github.com/${PREFIX}/releases for details"
+    exit 1
+  fi
+  # if version starts with 'v', remove it
+  TAG="$REALTAG"
+  VERSION=${TAG#v}
+}
+adjust_format() {
+  # change format (tar.gz or zip) based on OS
+  case ${OS} in
+    windows) FORMAT=zip ;;
+  esac
+  true
+}
+adjust_os() {
+  # adjust archive name based on OS
+  true
+}
+adjust_arch() {
+  # adjust archive name based on ARCH
+  true
+}
+
+cat /dev/null <<EOF
+------------------------------------------------------------------------
+https://github.com/client9/shlib - portable posix shell functions
+Public domain - http://unlicense.org
+https://github.com/client9/shlib/blob/master/LICENSE.md
+but credit (and pull requests) appreciated.
+------------------------------------------------------------------------
+EOF
+is_command() {
+  command -v "$1" >/dev/null
+}
+echoerr() {
+  echo "$@" 1>&2
+}
+log_prefix() {
+  echo "$0"
+}
+_logp=6
+log_set_priority() {
+  _logp="$1"
+}
+log_priority() {
+  if test -z "$1"; then
+    echo "$_logp"
+    return
+  fi
+  [ "$1" -le "$_logp" ]
+}
+log_tag() {
+  case $1 in
+    0) echo "emerg" ;;
+    1) echo "alert" ;;
+    2) echo "crit" ;;
+    3) echo "err" ;;
+    4) echo "warning" ;;
+    5) echo "notice" ;;
+    6) echo "info" ;;
+    7) echo "debug" ;;
+    *) echo "$1" ;;
+  esac
+}
+log_debug() {
+  log_priority 7 || return 0
+  echoerr "$(log_prefix)" "$(log_tag 7)" "$@"
+}
+log_info() {
+  log_priority 6 || return 0
+  echoerr "$(log_prefix)" "$(log_tag 6)" "$@"
+}
+log_err() {
+  log_priority 3 || return 0
+  echoerr "$(log_prefix)" "$(log_tag 3)" "$@"
+}
+log_crit() {
+  log_priority 2 || return 0
+  echoerr "$(log_prefix)" "$(log_tag 2)" "$@"
+}
+uname_os() {
+  os=$(uname -s | tr '[:upper:]' '[:lower:]')
+  case "$os" in
+    cygwin_nt*) os="windows" ;;
+    mingw*) os="windows" ;;
+    msys_nt*) os="windows" ;;
+  esac
+  echo "$os"
+}
+uname_arch() {
+  arch=$(uname -m)
+  case $arch in
+    x86_64) arch="amd64" ;;
+    x86) arch="386" ;;
+    i686) arch="386" ;;
+    i386) arch="386" ;;
+    aarch64) arch="arm64" ;;
+    armv5*) arch="armv5" ;;
+    armv6*) arch="armv6" ;;
+    armv7*) arch="armv7" ;;
+  esac
+  echo ${arch}
+}
+uname_os_check() {
+  os=$(uname_os)
+  case "$os" in
+    darwin) return 0 ;;
+    dragonfly) return 0 ;;
+    freebsd) return 0 ;;
+    linux) return 0 ;;
+    android) return 0 ;;
+    nacl) return 0 ;;
+    netbsd) return 0 ;;
+    openbsd) return 0 ;;
+    plan9) return 0 ;;
+    solaris) return 0 ;;
+    windows) return 0 ;;
+  esac
+  log_crit "uname_os_check '$(uname -s)' got converted to '$os' which is not a GOOS value. Please file bug at https://github.com/client9/shlib"
+  return 1
+}
+uname_arch_check() {
+  arch=$(uname_arch)
+  case "$arch" in
+    386) return 0 ;;
+    amd64) return 0 ;;
+    arm64) return 0 ;;
+    armv5) return 0 ;;
+    armv6) return 0 ;;
+    armv7) return 0 ;;
+    ppc64) return 0 ;;
+    ppc64le) return 0 ;;
+    mips) return 0 ;;
+    mipsle) return 0 ;;
+    mips64) return 0 ;;
+    mips64le) return 0 ;;
+    s390x) return 0 ;;
+    amd64p32) return 0 ;;
+  esac
+  log_crit "uname_arch_check '$(uname -m)' got converted to '$arch' which is not a GOARCH value.  Please file bug report at https://github.com/client9/shlib"
+  return 1
+}
+untar() {
+  tarball=$1
+  case "${tarball}" in
+    *.tar.gz | *.tgz) tar --no-same-owner -xzf "${tarball}" ;;
+    *.tar) tar --no-same-owner -xf "${tarball}" ;;
+    *.zip) unzip "${tarball}" ;;
+    *)
+      log_err "untar unknown archive format for ${tarball}"
+      return 1
+      ;;
+  esac
+}
+http_download_curl() {
+  local_file=$1
+  source_url=$2
+  header=$3
+  if [ -z "$header" ]; then
+    code=$(curl -w '%{http_code}' -sL -o "$local_file" "$source_url")
+  else
+    code=$(curl -w '%{http_code}' -sL -H "$header" -o "$local_file" "$source_url")
+  fi
+  if [ "$code" != "200" ]; then
+    log_debug "http_download_curl received HTTP status $code"
+    return 1
+  fi
+  return 0
+}
+http_download_wget() {
+  local_file=$1
+  source_url=$2
+  header=$3
+  if [ -z "$header" ]; then
+    wget -q -O "$local_file" "$source_url"
+  else
+    wget -q --header "$header" -O "$local_file" "$source_url"
+  fi
+}
+http_download() {
+  log_debug "http_download $2"
+  if is_command curl; then
+    http_download_curl "$@"
+    return
+  elif is_command wget; then
+    http_download_wget "$@"
+    return
+  fi
+  log_crit "http_download unable to find wget or curl"
+  return 1
+}
+http_copy() {
+  tmp=$(mktemp)
+  http_download "${tmp}" "$1" "$2" || return 1
+  body=$(cat "$tmp")
+  rm -f "${tmp}"
+  echo "$body"
+}
+github_release() {
+  owner_repo=$1
+  version=$2
+  test -z "$version" && version="latest"
+  giturl="https://github.com/${owner_repo}/releases/${version}"
+  json=$(http_copy "$giturl" "Accept:application/json")
+  test -z "$json" && return 1
+  version=$(echo "$json" | tr -s '\n' ' ' | sed 's/.*"tag_name":"//' | sed 's/".*//')
+  test -z "$version" && return 1
+  echo "$version"
+}
+hash_sha256() {
+  TARGET=${1:-/dev/stdin}
+  if is_command gsha256sum; then
+    hash=$(gsha256sum "$TARGET") || return 1
+    echo "$hash" | cut -d ' ' -f 1
+  elif is_command sha256sum; then
+    hash=$(sha256sum "$TARGET") || return 1
+    echo "$hash" | cut -d ' ' -f 1
+  elif is_command shasum; then
+    hash=$(shasum -a 256 "$TARGET" 2>/dev/null) || return 1
+    echo "$hash" | cut -d ' ' -f 1
+  elif is_command openssl; then
+    hash=$(openssl -dst openssl dgst -sha256 "$TARGET") || return 1
+    echo "$hash" | cut -d ' ' -f a
+  else
+    log_crit "hash_sha256 unable to find command to compute sha-256 hash"
+    return 1
+  fi
+}
+hash_sha256_verify() {
+  TARGET=$1
+  checksums=$2
+  if [ -z "$checksums" ]; then
+    log_err "hash_sha256_verify checksum file not specified in arg2"
+    return 1
+  fi
+  BASENAME=${TARGET##*/}
+  want=$(grep "${BASENAME}" "${checksums}" 2>/dev/null | tr '\t' ' ' | cut -d ' ' -f 1)
+  if [ -z "$want" ]; then
+    log_err "hash_sha256_verify unable to find checksum for '${TARGET}' in '${checksums}'"
+    return 1
+  fi
+  got=$(hash_sha256 "$TARGET")
+  if [ "$want" != "$got" ]; then
+    log_err "hash_sha256_verify checksum for '$TARGET' did not verify ${want} vs $got"
+    return 1
+  fi
+}
+cat /dev/null <<EOF
+------------------------------------------------------------------------
+End of functions from https://github.com/client9/shlib
+------------------------------------------------------------------------
+EOF
+
+PROJECT_NAME="task"
+OWNER=go-task
+REPO="task"
+BINARY=task
+FORMAT=tar.gz
+OS=$(uname_os)
+ARCH=$(uname_arch)
+PREFIX="$OWNER/$REPO"
+
+# use in logging routines
+log_prefix() {
+	echo "$PREFIX"
+}
+PLATFORM="${OS}/${ARCH}"
+GITHUB_DOWNLOAD=https://github.com/${OWNER}/${REPO}/releases/download
+
+uname_os_check "$OS"
+uname_arch_check "$ARCH"
+
+parse_args "$@"
+
+get_binaries
+
+tag_to_version
+
+adjust_format
+
+adjust_os
+
+adjust_arch
+
+log_info "found version: ${VERSION} for ${TAG}/${OS}/${ARCH}"
+
+NAME=${BINARY}_${OS}_${ARCH}
+TARBALL=${NAME}.${FORMAT}
+TARBALL_URL=${GITHUB_DOWNLOAD}/${TAG}/${TARBALL}
+CHECKSUM=task_checksums.txt
+CHECKSUM_URL=${GITHUB_DOWNLOAD}/${TAG}/${CHECKSUM}
+
+
+execute

internal/compiler/compiler.go

@@ -0,0 +1,14 @@
+package compiler
+
+import (
+	"github.com/go-task/task/v3/taskfile"
+)
+
+// Compiler handles compilation of a task before its execution.
+// E.g. variable merger, template processing, etc.
+type Compiler interface {
+	GetVariables(t *taskfile.Task, call taskfile.Call) (*taskfile.Vars, error)
+	FastGetVariables(t *taskfile.Task, call taskfile.Call) (*taskfile.Vars, error)
+	HandleDynamicVar(v taskfile.Var, dir string) (string, error)
+	ResetCache()
+}

internal/compiler/env.go

@@ -0,0 +1,20 @@
+package compiler
+
+import (
+	"os"
+	"strings"
+
+	"github.com/go-task/task/v3/taskfile"
+)
+
+// GetEnviron the all return all environment variables encapsulated on a
+// taskfile.Vars
+func GetEnviron() *taskfile.Vars {
+	m := &taskfile.Vars{}
+	for _, e := range os.Environ() {
+		keyVal := strings.SplitN(e, "=", 2)
+		key, val := keyVal[0], keyVal[1]
+		m.Set(key, taskfile.Var{Static: val})
+	}
+	return m
+}

internal/compiler/v2/compiler_v2.go

@@ -0,0 +1,127 @@
+package v2
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"strings"
+	"sync"
+
+	"github.com/go-task/task/v3/internal/compiler"
+	"github.com/go-task/task/v3/internal/execext"
+	"github.com/go-task/task/v3/internal/logger"
+	"github.com/go-task/task/v3/internal/templater"
+	"github.com/go-task/task/v3/taskfile"
+)
+
+var _ compiler.Compiler = &CompilerV2{}
+
+type CompilerV2 struct {
+	Dir string
+
+	Taskvars     *taskfile.Vars
+	TaskfileVars *taskfile.Vars
+
+	Expansions int
+
+	Logger *logger.Logger
+
+	dynamicCache   map[string]string
+	muDynamicCache sync.Mutex
+}
+
+// FastGetVariables is a no-op on v2
+func (c *CompilerV2) FastGetVariables(t *taskfile.Task, call taskfile.Call) (*taskfile.Vars, error) {
+	return c.GetVariables(t, call)
+}
+
+// GetVariables returns fully resolved variables following the priority order:
+// 1. Task variables
+// 2. Call variables
+// 3. Taskfile variables
+// 4. Taskvars file variables
+// 5. Environment variables
+func (c *CompilerV2) GetVariables(t *taskfile.Task, call taskfile.Call) (*taskfile.Vars, error) {
+	vr := varResolver{
+		c:    c,
+		vars: compiler.GetEnviron(),
+	}
+	vr.vars.Set("TASK", taskfile.Var{Static: t.Task})
+
+	for _, vars := range []*taskfile.Vars{c.Taskvars, c.TaskfileVars, call.Vars, t.Vars} {
+		for i := 0; i < c.Expansions; i++ {
+			vr.merge(vars)
+		}
+	}
+	return vr.vars, vr.err
+}
+
+type varResolver struct {
+	c    *CompilerV2
+	vars *taskfile.Vars
+	err  error
+}
+
+func (vr *varResolver) merge(vars *taskfile.Vars) {
+	if vr.err != nil {
+		return
+	}
+	tr := templater.Templater{Vars: vr.vars}
+	vars.Range(func(k string, v taskfile.Var) error {
+		v = taskfile.Var{
+			Static: tr.Replace(v.Static),
+			Sh:     tr.Replace(v.Sh),
+		}
+		static, err := vr.c.HandleDynamicVar(v, "")
+		if err != nil {
+			vr.err = err
+			return err
+		}
+		vr.vars.Set(k, taskfile.Var{Static: static})
+		return nil
+	})
+	vr.err = tr.Err()
+}
+
+func (c *CompilerV2) HandleDynamicVar(v taskfile.Var, _ string) (string, error) {
+	if v.Static != "" || v.Sh == "" {
+		return v.Static, nil
+	}
+
+	c.muDynamicCache.Lock()
+	defer c.muDynamicCache.Unlock()
+
+	if c.dynamicCache == nil {
+		c.dynamicCache = make(map[string]string, 30)
+	}
+	if result, ok := c.dynamicCache[v.Sh]; ok {
+		return result, nil
+	}
+
+	var stdout bytes.Buffer
+	opts := &execext.RunCommandOptions{
+		Command: v.Sh,
+		Stdout:  &stdout,
+		Stderr:  c.Logger.Stderr,
+	}
+	if err := execext.RunCommand(context.Background(), opts); err != nil {
+		return "", fmt.Errorf(`task: Command "%s" in taskvars file failed: %s`, opts.Command, err)
+	}
+
+	// Trim a single trailing newline from the result to make most command
+	// output easier to use in shell commands.
+	result := strings.TrimSuffix(stdout.String(), "\n")
+
+	c.dynamicCache[v.Sh] = result
+	c.Logger.VerboseErrf(logger.Magenta, `task: dynamic variable: '%s' result: '%s'`, v.Sh, result)
+
+	return result, nil
+}
+
+// ResetCache clear the dymanic variables cache
+func (c *CompilerV2) ResetCache() {
+	c.muDynamicCache.Lock()
+	defer c.muDynamicCache.Unlock()
+
+	c.dynamicCache = nil
+}

internal/compiler/v3/compiler_v3.go

@@ -0,0 +1,147 @@
+package v3
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"path/filepath"
+	"strings"
+	"sync"
+
+	"github.com/go-task/task/v3/internal/compiler"
+	"github.com/go-task/task/v3/internal/execext"
+	"github.com/go-task/task/v3/internal/logger"
+	"github.com/go-task/task/v3/internal/templater"
+	"github.com/go-task/task/v3/taskfile"
+)
+
+var _ compiler.Compiler = &CompilerV3{}
+
+type CompilerV3 struct {
+	Dir string
+
+	TaskfileEnv  *taskfile.Vars
+	TaskfileVars *taskfile.Vars
+
+	Logger *logger.Logger
+
+	dynamicCache   map[string]string
+	muDynamicCache sync.Mutex
+}
+
+func (c *CompilerV3) GetVariables(t *taskfile.Task, call taskfile.Call) (*taskfile.Vars, error) {
+	return c.getVariables(t, call, true)
+}
+
+func (c *CompilerV3) FastGetVariables(t *taskfile.Task, call taskfile.Call) (*taskfile.Vars, error) {
+	return c.getVariables(t, call, false)
+}
+
+func (c *CompilerV3) getVariables(t *taskfile.Task, call taskfile.Call, evaluateShVars bool) (*taskfile.Vars, error) {
+	result := compiler.GetEnviron()
+	result.Set("TASK", taskfile.Var{Static: t.Task})
+
+	getRangeFunc := func(dir string) func(k string, v taskfile.Var) error {
+		return func(k string, v taskfile.Var) error {
+			tr := templater.Templater{Vars: result, RemoveNoValue: true}
+
+			if !evaluateShVars {
+				result.Set(k, taskfile.Var{Static: tr.Replace(v.Static)})
+				return nil
+			}
+
+			v = taskfile.Var{
+				Static: tr.Replace(v.Static),
+				Sh:     tr.Replace(v.Sh),
+				Dir:    v.Dir,
+			}
+			if err := tr.Err(); err != nil {
+				return err
+			}
+			static, err := c.HandleDynamicVar(v, dir)
+			if err != nil {
+				return err
+			}
+			result.Set(k, taskfile.Var{Static: static})
+			return nil
+		}
+	}
+	rangeFunc := getRangeFunc(c.Dir)
+
+	if err := c.TaskfileEnv.Range(rangeFunc); err != nil {
+		return nil, err
+	}
+	if err := c.TaskfileVars.Range(rangeFunc); err != nil {
+		return nil, err
+	}
+	if err := call.Vars.Range(rangeFunc); err != nil {
+		return nil, err
+	}
+
+	// NOTE(@andreynering): We're manually joining these paths here because
+	// this is the raw task, not the compiled one.
+	tr := templater.Templater{Vars: result, RemoveNoValue: true}
+	dir := tr.Replace(t.Dir)
+	if err := tr.Err(); err != nil {
+		return nil, err
+	}
+	if !filepath.IsAbs(dir) {
+		dir = filepath.Join(c.Dir, dir)
+	}
+	taskRangeFunc := getRangeFunc(dir)
+
+	if err := t.Vars.Range(taskRangeFunc); err != nil {
+		return nil, err
+	}
+
+	return result, nil
+}
+
+func (c *CompilerV3) HandleDynamicVar(v taskfile.Var, dir string) (string, error) {
+	if v.Static != "" || v.Sh == "" {
+		return v.Static, nil
+	}
+
+	c.muDynamicCache.Lock()
+	defer c.muDynamicCache.Unlock()
+
+	if c.dynamicCache == nil {
+		c.dynamicCache = make(map[string]string, 30)
+	}
+	if result, ok := c.dynamicCache[v.Sh]; ok {
+		return result, nil
+	}
+
+	// NOTE(@andreynering): If a var have a specific dir, use this instead
+	if v.Dir != "" {
+		dir = v.Dir
+	}
+
+	var stdout bytes.Buffer
+	opts := &execext.RunCommandOptions{
+		Command: v.Sh,
+		Dir:     dir,
+		Stdout:  &stdout,
+		Stderr:  c.Logger.Stderr,
+	}
+	if err := execext.RunCommand(context.Background(), opts); err != nil {
+		return "", fmt.Errorf(`task: Command "%s" in taskvars file failed: %s`, opts.Command, err)
+	}
+
+	// Trim a single trailing newline from the result to make most command
+	// output easier to use in shell commands.
+	result := strings.TrimSuffix(stdout.String(), "\n")
+
+	c.dynamicCache[v.Sh] = result
+	c.Logger.VerboseErrf(logger.Magenta, `task: dynamic variable: '%s' result: '%s'`, v.Sh, result)
+
+	return result, nil
+}
+
+// ResetCache clear the dymanic variables cache
+func (c *CompilerV3) ResetCache() {
+	c.muDynamicCache.Lock()
+	defer c.muDynamicCache.Unlock()
+
+	c.dynamicCache = nil
+}

internal/execext/devnull.go

@@ -0,0 +1,13 @@
+package execext
+
+import (
+	"io"
+)
+
+var _ io.ReadWriteCloser = devNull{}
+
+type devNull struct{}
+
+func (devNull) Read(p []byte) (int, error)  { return 0, io.EOF }
+func (devNull) Write(p []byte) (int, error) { return len(p), nil }
+func (devNull) Close() error                { return nil }

internal/execext/exec.go

@@ -0,0 +1,89 @@
+package execext
+
+import (
+	"context"
+	"errors"
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"mvdan.cc/sh/v3/expand"
+	"mvdan.cc/sh/v3/interp"
+	"mvdan.cc/sh/v3/shell"
+	"mvdan.cc/sh/v3/syntax"
+)
+
+// RunCommandOptions is the options for the RunCommand func
+type RunCommandOptions struct {
+	Command string
+	Dir     string
+	Env     []string
+	Stdin   io.Reader
+	Stdout  io.Writer
+	Stderr  io.Writer
+}
+
+var (
+	// ErrNilOptions is returned when a nil options is given
+	ErrNilOptions = errors.New("execext: nil options given")
+)
+
+// RunCommand runs a shell command
+func RunCommand(ctx context.Context, opts *RunCommandOptions) error {
+	if opts == nil {
+		return ErrNilOptions
+	}
+
+	p, err := syntax.NewParser().Parse(strings.NewReader(opts.Command), "")
+	if err != nil {
+		return err
+	}
+
+	environ := opts.Env
+	if len(environ) == 0 {
+		environ = os.Environ()
+	}
+
+	r, err := interp.New(
+		interp.Params("-e"),
+		interp.Dir(opts.Dir),
+		interp.Env(expand.ListEnviron(environ...)),
+		interp.OpenHandler(openHandler),
+		interp.StdIO(opts.Stdin, opts.Stdout, opts.Stderr),
+	)
+	if err != nil {
+		return err
+	}
+	return r.Run(ctx, p)
+}
+
+// IsExitError returns true the given error is an exis status error
+func IsExitError(err error) bool {
+	if _, ok := interp.IsExitStatus(err); ok {
+		return true
+	}
+	return false
+}
+
+// Expand is a helper to mvdan.cc/shell.Fields that returns the first field
+// if available.
+func Expand(s string) (string, error) {
+	s = filepath.ToSlash(s)
+	s = strings.Replace(s, " ", `\ `, -1)
+	fields, err := shell.Fields(s, nil)
+	if err != nil {
+		return "", err
+	}
+	if len(fields) > 0 {
+		return fields[0], nil
+	}
+	return "", nil
+}
+
+func openHandler(ctx context.Context, path string, flag int, perm os.FileMode) (io.ReadWriteCloser, error) {
+	if path == "/dev/null" {
+		return devNull{}, nil
+	}
+	return interp.DefaultOpenHandler()(ctx, path, flag, perm)
+}

internal/logger/logger.go

@@ -0,0 +1,64 @@
+package logger
+
+import (
+	"io"
+
+	"github.com/fatih/color"
+)
+
+type PrintFunc func(io.Writer, string, ...interface{})
+
+var (
+	Default PrintFunc = color.New(color.Reset).FprintfFunc()
+	Blue    PrintFunc = color.New(color.FgBlue).FprintfFunc()
+	Green   PrintFunc = color.New(color.FgGreen).FprintfFunc()
+	Cyan    PrintFunc = color.New(color.FgCyan).FprintfFunc()
+	Yellow  PrintFunc = color.New(color.FgYellow).FprintfFunc()
+	Magenta PrintFunc = color.New(color.FgMagenta).FprintfFunc()
+	Red     PrintFunc = color.New(color.FgRed).FprintfFunc()
+)
+
+// Logger is just a wrapper that prints stuff to STDOUT or STDERR,
+// with optional color.
+type Logger struct {
+	Stdout  io.Writer
+	Stderr  io.Writer
+	Verbose bool
+	Color   bool
+}
+
+// Outf prints stuff to STDOUT.
+func (l *Logger) Outf(print PrintFunc, s string, args ...interface{}) {
+	if len(args) == 0 {
+		s, args = "%s", []interface{}{s}
+	}
+	if !l.Color {
+		print = Default
+	}
+	print(l.Stdout, s+"\n", args...)
+}
+
+// VerboseOutf prints stuff to STDOUT if verbose mode is enabled.
+func (l *Logger) VerboseOutf(print PrintFunc, s string, args ...interface{}) {
+	if l.Verbose {
+		l.Outf(print, s, args...)
+	}
+}
+
+// Errf prints stuff to STDERR.
+func (l *Logger) Errf(print PrintFunc, s string, args ...interface{}) {
+	if len(args) == 0 {
+		s, args = "%s", []interface{}{s}
+	}
+	if !l.Color {
+		print = Default
+	}
+	print(l.Stderr, s+"\n", args...)
+}
+
+// VerboseErrf prints stuff to STDERR if verbose mode is enabled.
+func (l *Logger) VerboseErrf(print PrintFunc, s string, args ...interface{}) {
+	if l.Verbose {
+		l.Errf(print, s, args...)
+	}
+}

internal/output/group.go

@@ -0,0 +1,26 @@
+package output
+
+import (
+	"bytes"
+	"io"
+)
+
+type Group struct{}
+
+func (Group) WrapWriter(w io.Writer, _ string) io.Writer {
+	return &groupWriter{writer: w}
+}
+
+type groupWriter struct {
+	writer io.Writer
+	buff   bytes.Buffer
+}
+
+func (gw *groupWriter) Write(p []byte) (int, error) {
+	return gw.buff.Write(p)
+}
+
+func (gw *groupWriter) Close() error {
+	_, err := io.Copy(gw.writer, &gw.buff)
+	return err
+}

internal/output/interleaved.go

@@ -0,0 +1,11 @@
+package output
+
+import (
+	"io"
+)
+
+type Interleaved struct{}
+
+func (Interleaved) WrapWriter(w io.Writer, _ string) io.Writer {
+	return w
+}

internal/output/output.go

@@ -0,0 +1,9 @@
+package output
+
+import (
+	"io"
+)
+
+type Output interface {
+	WrapWriter(w io.Writer, prefix string) io.Writer
+}

internal/output/output_test.go

@@ -0,0 +1,63 @@
+package output_test
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"github.com/go-task/task/v3/internal/output"
+)
+
+func TestInterleaved(t *testing.T) {
+	var b bytes.Buffer
+	var o output.Output = output.Interleaved{}
+	var w = o.WrapWriter(&b, "")
+
+	fmt.Fprintln(w, "foo\nbar")
+	assert.Equal(t, "foo\nbar\n", b.String())
+	fmt.Fprintln(w, "baz")
+	assert.Equal(t, "foo\nbar\nbaz\n", b.String())
+}
+
+func TestGroup(t *testing.T) {
+	var b bytes.Buffer
+	var o output.Output = output.Group{}
+	var w = o.WrapWriter(&b, "").(io.WriteCloser)
+
+	fmt.Fprintln(w, "foo\nbar")
+	assert.Equal(t, "", b.String())
+	fmt.Fprintln(w, "baz")
+	assert.Equal(t, "", b.String())
+	assert.NoError(t, w.Close())
+	assert.Equal(t, "foo\nbar\nbaz\n", b.String())
+}
+
+func TestPrefixed(t *testing.T) {
+	var b bytes.Buffer
+	var o output.Output = output.Prefixed{}
+	var w = o.WrapWriter(&b, "prefix").(io.WriteCloser)
+
+	t.Run("simple use cases", func(t *testing.T) {
+		b.Reset()
+
+		fmt.Fprintln(w, "foo\nbar")
+		assert.Equal(t, "[prefix] foo\n[prefix] bar\n", b.String())
+		fmt.Fprintln(w, "baz")
+		assert.Equal(t, "[prefix] foo\n[prefix] bar\n[prefix] baz\n", b.String())
+	})
+
+	t.Run("multiple writes for a single line", func(t *testing.T) {
+		b.Reset()
+
+		for _, char := range []string{"T", "e", "s", "t", "!"} {
+			fmt.Fprint(w, char)
+			assert.Equal(t, "", b.String())
+		}
+
+		assert.NoError(t, w.Close())
+		assert.Equal(t, "[prefix] Test!\n", b.String())
+	})
+}

internal/output/prefixed.go

@@ -0,0 +1,65 @@
+package output
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"strings"
+)
+
+type Prefixed struct{}
+
+func (Prefixed) WrapWriter(w io.Writer, prefix string) io.Writer {
+	return &prefixWriter{writer: w, prefix: prefix}
+}
+
+type prefixWriter struct {
+	writer io.Writer
+	prefix string
+	buff   bytes.Buffer
+}
+
+func (pw *prefixWriter) Write(p []byte) (int, error) {
+	n, err := pw.buff.Write(p)
+	if err != nil {
+		return n, err
+	}
+
+	return n, pw.writeOutputLines(false)
+}
+
+func (pw *prefixWriter) Close() error {
+	return pw.writeOutputLines(true)
+}
+
+func (pw *prefixWriter) writeOutputLines(force bool) error {
+	for {
+		switch line, err := pw.buff.ReadString('\n'); err {
+		case nil:
+			if err = pw.writeLine(line); err != nil {
+				return err
+			}
+		case io.EOF:
+			// if this line was not a complete line, re-add to the buffer
+			if !force && !strings.HasSuffix(line, "\n") {
+				_, err = pw.buff.WriteString(line)
+				return err
+			}
+
+			return pw.writeLine(line)
+		default:
+			return err
+		}
+	}
+}
+
+func (pw *prefixWriter) writeLine(line string) error {
+	if line == "" {
+		return nil
+	}
+	if !strings.HasSuffix(line, "\n") {
+		line += "\n"
+	}
+	_, err := fmt.Fprintf(pw.writer, "[%s] %s", pw.prefix, line)
+	return err
+}

internal/status/checksum.go

@@ -0,0 +1,119 @@
+package status
+
+import (
+	"crypto/md5"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strings"
+)
+
+// Checksum validades if a task is up to date by calculating its source
+// files checksum
+type Checksum struct {
+	BaseDir   string
+	TaskDir   string
+	Task      string
+	Sources   []string
+	Generates []string
+	Dry       bool
+}
+
+// IsUpToDate implements the Checker interface
+func (c *Checksum) IsUpToDate() (bool, error) {
+	if len(c.Sources) == 0 {
+		return false, nil
+	}
+
+	checksumFile := c.checksumFilePath()
+
+	data, _ := ioutil.ReadFile(checksumFile)
+	oldMd5 := strings.TrimSpace(string(data))
+
+	sources, err := globs(c.TaskDir, c.Sources)
+	if err != nil {
+		return false, err
+	}
+
+	newMd5, err := c.checksum(sources...)
+	if err != nil {
+		return false, nil
+	}
+
+	if !c.Dry {
+		_ = os.MkdirAll(filepath.Join(c.BaseDir, ".task", "checksum"), 0755)
+		if err = ioutil.WriteFile(checksumFile, []byte(newMd5+"\n"), 0644); err != nil {
+			return false, err
+		}
+	}
+
+	if len(c.Generates) > 0 {
+		// For each specified 'generates' field, check whether the files actually exist
+		for _, g := range c.Generates {
+			generates, err := glob(c.TaskDir, g)
+			if os.IsNotExist(err) {
+				return false, nil
+			}
+			if err != nil {
+				return false, err
+			}
+			if len(generates) == 0 {
+				return false, nil
+			}
+		}
+	}
+
+	return oldMd5 == newMd5, nil
+}
+
+func (c *Checksum) checksum(files ...string) (string, error) {
+	h := md5.New()
+
+	for _, f := range files {
+		// also sum the filename, so checksum changes for renaming a file
+		if _, err := io.Copy(h, strings.NewReader(filepath.Base(f))); err != nil {
+			return "", err
+		}
+		f, err := os.Open(f)
+		if err != nil {
+			return "", err
+		}
+		if _, err = io.Copy(h, f); err != nil {
+			return "", err
+		}
+	}
+
+	return fmt.Sprintf("%x", h.Sum(nil)), nil
+}
+
+// Value implements the Checker Interface
+func (c *Checksum) Value() (interface{}, error) {
+	return c.checksum()
+}
+
+// OnError implements the Checker interface
+func (c *Checksum) OnError() error {
+	if len(c.Sources) == 0 {
+		return nil
+	}
+	return os.Remove(c.checksumFilePath())
+}
+
+// Kind implements the Checker Interface
+func (*Checksum) Kind() string {
+	return "checksum"
+}
+
+func (c *Checksum) checksumFilePath() string {
+	return filepath.Join(c.BaseDir, ".task", "checksum", c.normalizeFilename(c.Task))
+}
+
+var checksumFilenameRegexp = regexp.MustCompile("[^A-z0-9]")
+
+// replaces invalid caracters on filenames with "-"
+func (*Checksum) normalizeFilename(f string) string {
+	return checksumFilenameRegexp.ReplaceAllString(f, "-")
+}

internal/status/checksum_test.go

@@ -0,0 +1,21 @@
+package status
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestNormalizeFilename(t *testing.T) {
+	tests := []struct {
+		In, Out string
+	}{
+		{"foobarbaz", "foobarbaz"},
+		{"foo/bar/baz", "foo-bar-baz"},
+		{"foo@bar/baz", "foo-bar-baz"},
+		{"foo1bar2baz3", "foo1bar2baz3"},
+	}
+	for _, test := range tests {
+		assert.Equal(t, test.Out, (&Checksum{}).normalizeFilename(test.In))
+	}
+}

internal/status/glob.go

@@ -0,0 +1,50 @@
+package status
+
+import (
+	"os"
+	"path/filepath"
+	"sort"
+
+	"github.com/mattn/go-zglob"
+
+	"github.com/go-task/task/v3/internal/execext"
+)
+
+func globs(dir string, globs []string) ([]string, error) {
+	files := make([]string, 0)
+	for _, g := range globs {
+		f, err := glob(dir, g)
+		if err != nil {
+			continue
+		}
+		files = append(files, f...)
+	}
+	sort.Strings(files)
+	return files, nil
+}
+
+func glob(dir string, g string) ([]string, error) {
+	files := make([]string, 0)
+	if !filepath.IsAbs(g) {
+		g = filepath.Join(dir, g)
+	}
+	g, err := execext.Expand(g)
+	if err != nil {
+		return nil, err
+	}
+	fs, err := zglob.Glob(g)
+	if err != nil {
+		return nil, err
+	}
+	for _, f := range fs {
+		info, err := os.Stat(f)
+		if err != nil {
+			return nil, err
+		}
+		if info.IsDir() {
+			continue
+		}
+		files = append(files, f)
+	}
+	return files, nil
+}

internal/status/none.go

@@ -0,0 +1,23 @@
+package status
+
+// None is a no-op Checker
+type None struct{}
+
+// IsUpToDate implements the Checker interface
+func (None) IsUpToDate() (bool, error) {
+	return false, nil
+}
+
+// Value implements the Checker interface
+func (None) Value() (interface{}, error) {
+	return "", nil
+}
+
+func (None) Kind() string {
+	return "none"
+}
+
+// OnError implements the Checker interface
+func (None) OnError() error {
+	return nil
+}

internal/status/status.go

@@ -0,0 +1,15 @@
+package status
+
+var (
+	_ Checker = &Timestamp{}
+	_ Checker = &Checksum{}
+	_ Checker = None{}
+)
+
+// Checker is an interface that checks if the status is up-to-date
+type Checker interface {
+	IsUpToDate() (bool, error)
+	Value() (interface{}, error)
+	OnError() error
+	Kind() string
+}

internal/status/timestamp.go

@@ -0,0 +1,108 @@
+package status
+
+import (
+	"os"
+	"time"
+)
+
+// Timestamp checks if any source change compared with the generated files,
+// using file modifications timestamps.
+type Timestamp struct {
+	Dir       string
+	Sources   []string
+	Generates []string
+}
+
+// IsUpToDate implements the Checker interface
+func (t *Timestamp) IsUpToDate() (bool, error) {
+	if len(t.Sources) == 0 || len(t.Generates) == 0 {
+		return false, nil
+	}
+
+	sources, err := globs(t.Dir, t.Sources)
+	if err != nil {
+		return false, nil
+	}
+	generates, err := globs(t.Dir, t.Generates)
+	if err != nil {
+		return false, nil
+	}
+
+	sourcesMaxTime, err := getMaxTime(sources...)
+	if err != nil || sourcesMaxTime.IsZero() {
+		return false, nil
+	}
+
+	generatesMinTime, err := getMinTime(generates...)
+	if err != nil || generatesMinTime.IsZero() {
+		return false, nil
+	}
+
+	return !generatesMinTime.Before(sourcesMaxTime), nil
+}
+
+func (t *Timestamp) Kind() string {
+	return "timestamp"
+}
+
+// Value implements the Checker Interface
+func (t *Timestamp) Value() (interface{}, error) {
+	sources, err := globs(t.Dir, t.Sources)
+	if err != nil {
+		return time.Now(), err
+	}
+
+	sourcesMaxTime, err := getMaxTime(sources...)
+	if err != nil {
+		return time.Now(), err
+	}
+
+	if sourcesMaxTime.IsZero() {
+		return time.Unix(0, 0), nil
+	}
+
+	return sourcesMaxTime, nil
+}
+
+func getMinTime(files ...string) (time.Time, error) {
+	var t time.Time
+	for _, f := range files {
+		info, err := os.Stat(f)
+		if err != nil {
+			return time.Time{}, err
+		}
+		t = minTime(t, info.ModTime())
+	}
+	return t, nil
+}
+
+func getMaxTime(files ...string) (time.Time, error) {
+	var t time.Time
+	for _, f := range files {
+		info, err := os.Stat(f)
+		if err != nil {
+			return time.Time{}, err
+		}
+		t = maxTime(t, info.ModTime())
+	}
+	return t, nil
+}
+
+func minTime(a, b time.Time) time.Time {
+	if !a.IsZero() && a.Before(b) {
+		return a
+	}
+	return b
+}
+
+func maxTime(a, b time.Time) time.Time {
+	if a.After(b) {
+		return a
+	}
+	return b
+}
+
+// OnError implements the Checker interface
+func (*Timestamp) OnError() error {
+	return nil
+}

internal/summary/summary.go

@@ -0,0 +1,103 @@
+package summary
+
+import (
+	"strings"
+
+	"github.com/go-task/task/v3/internal/logger"
+	"github.com/go-task/task/v3/taskfile"
+)
+
+func PrintTasks(l *logger.Logger, t *taskfile.Taskfile, c []taskfile.Call) {
+	for i, call := range c {
+		PrintSpaceBetweenSummaries(l, i)
+		PrintTask(l, t.Tasks[call.Task])
+	}
+}
+
+func PrintSpaceBetweenSummaries(l *logger.Logger, i int) {
+	spaceRequired := i > 0
+	if !spaceRequired {
+		return
+	}
+
+	l.Outf(logger.Default, "")
+	l.Outf(logger.Default, "")
+}
+
+func PrintTask(l *logger.Logger, t *taskfile.Task) {
+	printTaskName(l, t)
+	printTaskDescribingText(t, l)
+	printTaskDependencies(l, t)
+	printTaskCommands(l, t)
+}
+
+func printTaskDescribingText(t *taskfile.Task, l *logger.Logger) {
+	if hasSummary(t) {
+		printTaskSummary(l, t)
+	} else if hasDescription(t) {
+		printTaskDescription(l, t)
+	} else {
+		printNoDescriptionOrSummary(l)
+	}
+}
+
+func hasSummary(t *taskfile.Task) bool {
+	return t.Summary != ""
+}
+
+func printTaskSummary(l *logger.Logger, t *taskfile.Task) {
+	lines := strings.Split(t.Summary, "\n")
+	for i, line := range lines {
+		notLastLine := i+1 < len(lines)
+		if notLastLine || line != "" {
+			l.Outf(logger.Default, line)
+		}
+	}
+}
+
+func printTaskName(l *logger.Logger, t *taskfile.Task) {
+	l.Outf(logger.Default, "task: %s", t.Name())
+	l.Outf(logger.Default, "")
+}
+
+func hasDescription(t *taskfile.Task) bool {
+	return t.Desc != ""
+}
+
+func printTaskDescription(l *logger.Logger, t *taskfile.Task) {
+	l.Outf(logger.Default, t.Desc)
+}
+
+func printNoDescriptionOrSummary(l *logger.Logger) {
+	l.Outf(logger.Default, "(task does not have description or summary)")
+}
+
+func printTaskDependencies(l *logger.Logger, t *taskfile.Task) {
+	if len(t.Deps) == 0 {
+		return
+	}
+
+	l.Outf(logger.Default, "")
+	l.Outf(logger.Default, "dependencies:")
+
+	for _, d := range t.Deps {
+		l.Outf(logger.Default, " - %s", d.Task)
+	}
+}
+
+func printTaskCommands(l *logger.Logger, t *taskfile.Task) {
+	if len(t.Cmds) == 0 {
+		return
+	}
+
+	l.Outf(logger.Default, "")
+	l.Outf(logger.Default, "commands:")
+	for _, c := range t.Cmds {
+		isCommand := c.Cmd != ""
+		if isCommand {
+			l.Outf(logger.Default, " - %s", c.Cmd)
+		} else {
+			l.Outf(logger.Default, " - Task: %s", c.Task)
+		}
+	}
+}

internal/summary/summary_test.go

@@ -0,0 +1,173 @@
+package summary_test
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"github.com/go-task/task/v3/internal/logger"
+	"github.com/go-task/task/v3/internal/summary"
+	"github.com/go-task/task/v3/taskfile"
+)
+
+func TestPrintsDependenciesIfPresent(t *testing.T) {
+	buffer, l := createDummyLogger()
+	task := &taskfile.Task{
+		Deps: []*taskfile.Dep{
+			{Task: "dep1"},
+			{Task: "dep2"},
+			{Task: "dep3"},
+		},
+	}
+
+	summary.PrintTask(&l, task)
+
+	assert.Contains(t, buffer.String(), "\ndependencies:\n - dep1\n - dep2\n - dep3\n")
+}
+
+func createDummyLogger() (*bytes.Buffer, logger.Logger) {
+	buffer := &bytes.Buffer{}
+	l := logger.Logger{
+		Stderr:  buffer,
+		Stdout:  buffer,
+		Verbose: false,
+	}
+	return buffer, l
+}
+
+func TestDoesNotPrintDependenciesIfMissing(t *testing.T) {
+	buffer, l := createDummyLogger()
+	task := &taskfile.Task{
+		Deps: []*taskfile.Dep{},
+	}
+
+	summary.PrintTask(&l, task)
+
+	assert.NotContains(t, buffer.String(), "dependencies:")
+}
+
+func TestPrintTaskName(t *testing.T) {
+	buffer, l := createDummyLogger()
+	task := &taskfile.Task{
+		Task: "my-task-name",
+	}
+
+	summary.PrintTask(&l, task)
+
+	assert.Contains(t, buffer.String(), "task: my-task-name\n")
+}
+
+func TestPrintTaskCommandsIfPresent(t *testing.T) {
+	buffer, l := createDummyLogger()
+	task := &taskfile.Task{
+		Cmds: []*taskfile.Cmd{
+			{Cmd: "command-1"},
+			{Cmd: "command-2"},
+			{Task: "task-1"},
+		},
+	}
+
+	summary.PrintTask(&l, task)
+
+	assert.Contains(t, buffer.String(), "\ncommands:\n")
+	assert.Contains(t, buffer.String(), "\n - command-1\n")
+	assert.Contains(t, buffer.String(), "\n - command-2\n")
+	assert.Contains(t, buffer.String(), "\n - Task: task-1\n")
+}
+
+func TestDoesNotPrintCommandIfMissing(t *testing.T) {
+	buffer, l := createDummyLogger()
+	task := &taskfile.Task{
+		Cmds: []*taskfile.Cmd{},
+	}
+
+	summary.PrintTask(&l, task)
+
+	assert.NotContains(t, buffer.String(), "commands")
+}
+
+func TestLayout(t *testing.T) {
+	buffer, l := createDummyLogger()
+	task := &taskfile.Task{
+		Task:    "sample-task",
+		Summary: "line1\nline2\nline3\n",
+		Deps: []*taskfile.Dep{
+			{Task: "dependency"},
+		},
+		Cmds: []*taskfile.Cmd{
+			{Cmd: "command"},
+		},
+	}
+
+	summary.PrintTask(&l, task)
+
+	assert.Equal(t, expectedOutput(), buffer.String())
+}
+
+func expectedOutput() string {
+	expected := `task: sample-task
+
+line1
+line2
+line3
+
+dependencies:
+ - dependency
+
+commands:
+ - command
+`
+	return expected
+}
+
+func TestPrintDescriptionAsFallback(t *testing.T) {
+	buffer, l := createDummyLogger()
+	taskWithoutSummary := &taskfile.Task{
+		Desc: "description",
+	}
+
+	taskWithSummary := &taskfile.Task{
+		Desc:    "description",
+		Summary: "summary",
+	}
+	taskWithoutSummaryOrDescription := &taskfile.Task{}
+
+	summary.PrintTask(&l, taskWithoutSummary)
+
+	assert.Contains(t, buffer.String(), "description")
+
+	buffer.Reset()
+	summary.PrintTask(&l, taskWithSummary)
+
+	assert.NotContains(t, buffer.String(), "description")
+
+	buffer.Reset()
+	summary.PrintTask(&l, taskWithoutSummaryOrDescription)
+
+	assert.Contains(t, buffer.String(), "\n(task does not have description or summary)\n")
+
+}
+
+func TestPrintAllWithSpaces(t *testing.T) {
+	buffer, l := createDummyLogger()
+
+	t1 := &taskfile.Task{Task: "t1"}
+	t2 := &taskfile.Task{Task: "t2"}
+	t3 := &taskfile.Task{Task: "t3"}
+
+	tasks := make(taskfile.Tasks, 3)
+	tasks["t1"] = t1
+	tasks["t2"] = t2
+	tasks["t3"] = t3
+
+	summary.PrintTasks(&l,
+		&taskfile.Taskfile{Tasks: tasks},
+		[]taskfile.Call{{Task: "t1"}, {Task: "t2"}, {Task: "t3"}})
+
+	assert.True(t, strings.HasPrefix(buffer.String(), "task: t1"))
+	assert.Contains(t, buffer.String(), "\n(task does not have description or summary)\n\n\ntask: t2")
+	assert.Contains(t, buffer.String(), "\n(task does not have description or summary)\n\n\ntask: t3")
+
+}

internal/templater/funcs.go

@@ -0,0 +1,52 @@
+package templater
+
+import (
+	"path/filepath"
+	"runtime"
+	"strings"
+	"text/template"
+
+	"github.com/go-task/slim-sprig"
+)
+
+var (
+	templateFuncs template.FuncMap
+)
+
+func init() {
+	taskFuncs := template.FuncMap{
+		"OS":   func() string { return runtime.GOOS },
+		"ARCH": func() string { return runtime.GOARCH },
+		"catLines": func(s string) string {
+			s = strings.Replace(s, "\r\n", " ", -1)
+			return strings.Replace(s, "\n", " ", -1)
+		},
+		"splitLines": func(s string) []string {
+			s = strings.Replace(s, "\r\n", "\n", -1)
+			return strings.Split(s, "\n")
+		},
+		"fromSlash": func(path string) string {
+			return filepath.FromSlash(path)
+		},
+		"toSlash": func(path string) string {
+			return filepath.ToSlash(path)
+		},
+		"exeExt": func() string {
+			if runtime.GOOS == "windows" {
+				return ".exe"
+			}
+			return ""
+		},
+		// IsSH is deprecated.
+		"IsSH": func() bool { return true },
+	}
+	// Deprecated aliases for renamed functions.
+	taskFuncs["FromSlash"] = taskFuncs["fromSlash"]
+	taskFuncs["ToSlash"] = taskFuncs["toSlash"]
+	taskFuncs["ExeExt"] = taskFuncs["exeExt"]
+
+	templateFuncs = sprig.TxtFuncMap()
+	for k, v := range taskFuncs {
+		templateFuncs[k] = v
+	}
+}

internal/templater/templater.go

@@ -0,0 +1,85 @@
+package templater
+
+import (
+	"bytes"
+	"strings"
+	"text/template"
+
+	"github.com/go-task/task/v3/taskfile"
+)
+
+// Templater is a help struct that allow us to call "replaceX" funcs multiple
+// times, without having to check for error each time. The first error that
+// happen will be assigned to r.err, and consecutive calls to funcs will just
+// return the zero value.
+type Templater struct {
+	Vars          *taskfile.Vars
+	RemoveNoValue bool
+
+	cacheMap map[string]interface{}
+	err      error
+}
+
+func (r *Templater) ResetCache() {
+	r.cacheMap = r.Vars.ToCacheMap()
+}
+
+func (r *Templater) Replace(str string) string {
+	if r.err != nil || str == "" {
+		return ""
+	}
+
+	templ, err := template.New("").Funcs(templateFuncs).Parse(str)
+	if err != nil {
+		r.err = err
+		return ""
+	}
+
+	if r.cacheMap == nil {
+		r.cacheMap = r.Vars.ToCacheMap()
+	}
+
+	var b bytes.Buffer
+	if err = templ.Execute(&b, r.cacheMap); err != nil {
+		r.err = err
+		return ""
+	}
+	if r.RemoveNoValue {
+		return strings.ReplaceAll(b.String(), "<no value>", "")
+	}
+	return b.String()
+}
+
+func (r *Templater) ReplaceSlice(strs []string) []string {
+	if r.err != nil || len(strs) == 0 {
+		return nil
+	}
+
+	new := make([]string, len(strs))
+	for i, str := range strs {
+		new[i] = r.Replace(str)
+	}
+	return new
+}
+
+func (r *Templater) ReplaceVars(vars *taskfile.Vars) *taskfile.Vars {
+	if r.err != nil || vars.Len() == 0 {
+		return nil
+	}
+
+	var new taskfile.Vars
+	vars.Range(func(k string, v taskfile.Var) error {
+		new.Set(k, taskfile.Var{
+			Static: r.Replace(v.Static),
+			Live:   v.Live,
+			Sh:     r.Replace(v.Sh),
+		})
+		return nil
+	})
+
+	return &new
+}
+
+func (r *Templater) Err() error {
+	return r.err
+}

precondition.go

@@ -0,0 +1,32 @@
+package task
+
+import (
+	"context"
+	"errors"
+
+	"github.com/go-task/task/v3/internal/execext"
+	"github.com/go-task/task/v3/internal/logger"
+	"github.com/go-task/task/v3/taskfile"
+)
+
+var (
+	// ErrPreconditionFailed is returned when a precondition fails
+	ErrPreconditionFailed = errors.New("task: precondition not met")
+)
+
+func (e *Executor) areTaskPreconditionsMet(ctx context.Context, t *taskfile.Task) (bool, error) {
+	for _, p := range t.Preconditions {
+		err := execext.RunCommand(ctx, &execext.RunCommandOptions{
+			Command: p.Sh,
+			Dir:     t.Dir,
+			Env:     getEnviron(t),
+		})
+
+		if err != nil {
+			e.Logger.Errf(logger.Magenta, "task: %s", p.Msg)
+			return false, ErrPreconditionFailed
+		}
+	}
+
+	return true, nil
+}

status.go

@@ -0,0 +1,102 @@
+package task
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/go-task/task/v3/internal/execext"
+	"github.com/go-task/task/v3/internal/logger"
+	"github.com/go-task/task/v3/internal/status"
+	"github.com/go-task/task/v3/taskfile"
+)
+
+// Status returns an error if any the of given tasks is not up-to-date
+func (e *Executor) Status(ctx context.Context, calls ...taskfile.Call) error {
+	for _, call := range calls {
+		t, err := e.CompiledTask(call)
+		if err != nil {
+			return err
+		}
+		isUpToDate, err := e.isTaskUpToDate(ctx, t)
+		if err != nil {
+			return err
+		}
+		if !isUpToDate {
+			return fmt.Errorf(`task: Task "%s" is not up-to-date`, t.Name())
+		}
+	}
+	return nil
+}
+
+func (e *Executor) isTaskUpToDate(ctx context.Context, t *taskfile.Task) (bool, error) {
+	if len(t.Status) > 0 {
+		return e.isTaskUpToDateStatus(ctx, t)
+	}
+
+	checker, err := e.getStatusChecker(t)
+	if err != nil {
+		return false, err
+	}
+
+	return checker.IsUpToDate()
+}
+
+func (e *Executor) statusOnError(t *taskfile.Task) error {
+	checker, err := e.getStatusChecker(t)
+	if err != nil {
+		return err
+	}
+	return checker.OnError()
+}
+
+func (e *Executor) getStatusChecker(t *taskfile.Task) (status.Checker, error) {
+	method := t.Method
+	if method == "" {
+		method = e.Taskfile.Method
+	}
+	switch method {
+	case "timestamp":
+		return e.timestampChecker(t), nil
+	case "checksum":
+		return e.checksumChecker(t), nil
+	case "none":
+		return status.None{}, nil
+	default:
+		return nil, fmt.Errorf(`task: invalid method "%s"`, method)
+	}
+}
+
+func (e *Executor) timestampChecker(t *taskfile.Task) status.Checker {
+	return &status.Timestamp{
+		Dir:       t.Dir,
+		Sources:   t.Sources,
+		Generates: t.Generates,
+	}
+}
+
+func (e *Executor) checksumChecker(t *taskfile.Task) status.Checker {
+	return &status.Checksum{
+		BaseDir:   e.Dir,
+		TaskDir:   t.Dir,
+		Task:      t.Name(),
+		Sources:   t.Sources,
+		Generates: t.Generates,
+		Dry:       e.Dry,
+	}
+}
+
+func (e *Executor) isTaskUpToDateStatus(ctx context.Context, t *taskfile.Task) (bool, error) {
+	for _, s := range t.Status {
+		err := execext.RunCommand(ctx, &execext.RunCommandOptions{
+			Command: s,
+			Dir:     t.Dir,
+			Env:     getEnviron(t),
+		})
+		if err != nil {
+			e.Logger.VerboseOutf(logger.Yellow, "task: status command %s exited non-zero: %s", s, err)
+			return false, nil
+		}
+		e.Logger.VerboseOutf(logger.Yellow, "task: status command %s exited zero", s)
+	}
+	return true, nil
+}

task.go

@@ -1,137 +1,430 @@
 package task
 
 import (
+	"context"
+	"errors"
 	"fmt"
-	"io/ioutil"
-	"log"
+	"io"
 	"os"
-	"os/exec"
+	"sync"
+	"sync/atomic"
 
-	"gopkg.in/yaml.v2"
+	"github.com/go-task/task/v3/internal/compiler"
+	compilerv2 "github.com/go-task/task/v3/internal/compiler/v2"
+	compilerv3 "github.com/go-task/task/v3/internal/compiler/v3"
+	"github.com/go-task/task/v3/internal/execext"
+	"github.com/go-task/task/v3/internal/logger"
+	"github.com/go-task/task/v3/internal/output"
+	"github.com/go-task/task/v3/internal/summary"
+	"github.com/go-task/task/v3/taskfile"
+	"github.com/go-task/task/v3/taskfile/read"
+
+	"golang.org/x/sync/errgroup"
 )
 
-var (
-	TaskFilePath = "Taskfile.yml"
-	ShExists     bool
-	ShPath       string
-
-	Tasks = make(map[string]*Task)
+const (
+	// MaximumTaskCall is the max number of times a task can be called.
+	// This exists to prevent infinite loops on cyclic dependencies
+	MaximumTaskCall = 100
 )
 
-func init() {
-	var err error
-	ShPath, err = exec.LookPath("sh")
-	if err != nil {
-		return
-	}
-	ShExists = true
+// Executor executes a Taskfile
+type Executor struct {
+	Taskfile *taskfile.Taskfile
+
+	Dir         string
+	Entrypoint  string
+	Force       bool
+	Watch       bool
+	Verbose     bool
+	Silent      bool
+	Dry         bool
+	Summary     bool
+	Parallel    bool
+	Color       bool
+	Concurrency int
+
+	Stdin  io.Reader
+	Stdout io.Writer
+	Stderr io.Writer
+
+	Logger      *logger.Logger
+	Compiler    compiler.Compiler
+	Output      output.Output
+	OutputStyle string
+
+	taskvars *taskfile.Vars
+
+	concurrencySemaphore chan struct{}
+	taskCallCount        map[string]*int32
+	mkdirMutexMap        map[string]*sync.Mutex
 }
 
-type Task struct {
-	Cmds      []string
-	Deps      []string
-	Sources   []string
-	Generates []string
-}
-
-type TaskNotFoundError struct {
-	taskName string
-}
-
-func (err *TaskNotFoundError) Error() string {
-	return fmt.Sprintf(`Task "%s" not found`, err.taskName)
-}
-
-type TaskRunError struct {
-	taskName string
-	err      error
-}
-
-func (err *TaskRunError) Error() string {
-	return fmt.Sprintf(`Failed to run task "%s": %v`, err.taskName, err.err)
-}
-
-func Run() {
-	log.SetFlags(0)
-
-	args := os.Args[1:]
-	if len(args) == 0 {
-		log.Fatal("No argument given")
-	}
-
-	file, err := ioutil.ReadFile(TaskFilePath)
-	if err != nil {
-		if os.IsNotExist(err) {
-			log.Fatal("Taskfile.yml not found")
-		}
-		log.Fatal(err)
-	}
-
-	if err = yaml.Unmarshal(file, &Tasks); err != nil {
-		log.Fatal(err)
-	}
-
-	for _, a := range args {
-		if err = RunTask(a); err != nil {
-			log.Fatal(err)
+// Run runs Task
+func (e *Executor) Run(ctx context.Context, calls ...taskfile.Call) error {
+	// check if given tasks exist
+	for _, c := range calls {
+		if _, ok := e.Taskfile.Tasks[c.Task]; !ok {
+			// FIXME: move to the main package
+			e.PrintTasksHelp()
+			return &taskNotFoundError{taskName: c.Task}
 		}
 	}
-}
 
-func RunTask(name string) error {
-	t, ok := Tasks[name]
-	if !ok {
-		return &TaskNotFoundError{name}
-	}
-
-	if isTaskUpToDate(t) {
-		log.Printf(`Task "%s" is up to date`, name)
+	if e.Summary {
+		for i, c := range calls {
+			compiledTask, err := e.FastCompiledTask(c)
+			if err != nil {
+				return nil
+			}
+			summary.PrintSpaceBetweenSummaries(e.Logger, i)
+			summary.PrintTask(e.Logger, compiledTask)
+		}
 		return nil
 	}
 
-	for _, d := range t.Deps {
-		if err := RunTask(d); err != nil {
+	if e.Watch {
+		return e.watchTasks(calls...)
+	}
+
+	g, ctx := errgroup.WithContext(ctx)
+	for _, c := range calls {
+		c := c
+		if e.Parallel {
+			g.Go(func() error { return e.RunTask(ctx, c) })
+		} else {
+			if err := e.RunTask(ctx, c); err != nil {
+				return err
+			}
+		}
+	}
+	return g.Wait()
+}
+
+// Setup setups Executor's internal state
+func (e *Executor) Setup() error {
+	if e.Entrypoint == "" {
+		e.Entrypoint = "Taskfile.yml"
+	}
+
+	var err error
+	e.Taskfile, err = read.Taskfile(e.Dir, e.Entrypoint)
+	if err != nil {
+		return err
+	}
+
+	v, err := e.Taskfile.ParsedVersion()
+	if err != nil {
+		return err
+	}
+
+	if v < 3.0 {
+		e.taskvars, err = read.Taskvars(e.Dir)
+		if err != nil {
 			return err
 		}
 	}
 
-	for _, c := range t.Cmds {
-		if err := runCommand(c); err != nil {
-			return &TaskRunError{name, err}
+	if e.Stdin == nil {
+		e.Stdin = os.Stdin
+	}
+	if e.Stdout == nil {
+		e.Stdout = os.Stdout
+	}
+	if e.Stderr == nil {
+		e.Stderr = os.Stderr
+	}
+	e.Logger = &logger.Logger{
+		Stdout:  e.Stdout,
+		Stderr:  e.Stderr,
+		Verbose: e.Verbose,
+		Color:   e.Color,
+	}
+
+	if v < 2 {
+		return fmt.Errorf(`task: Taskfile versions prior to v2 are not supported anymore`)
+	}
+
+	// consider as equal to the greater version if round
+	if v == 2.0 {
+		v = 2.6
+	}
+
+	if v > 3.0 {
+		return fmt.Errorf(`task: Taskfile versions greater than v3.0 not implemented in the version of Task`)
+	}
+
+	// Color available only on v3
+	if v < 3 {
+		e.Logger.Color = false
+	}
+
+	if v < 3 {
+		e.Compiler = &compilerv2.CompilerV2{
+			Dir:          e.Dir,
+			Taskvars:     e.taskvars,
+			TaskfileVars: e.Taskfile.Vars,
+			Expansions:   e.Taskfile.Expansions,
+			Logger:       e.Logger,
+		}
+	} else {
+		e.Compiler = &compilerv3.CompilerV3{
+			Dir:          e.Dir,
+			TaskfileEnv:  e.Taskfile.Env,
+			TaskfileVars: e.Taskfile.Vars,
+			Logger:       e.Logger,
+		}
+	}
+
+	if v < 2.1 && e.Taskfile.Output != "" {
+		return fmt.Errorf(`task: Taskfile option "output" is only available starting on Taskfile version v2.1`)
+	}
+	if v < 2.2 && e.Taskfile.Includes.Len() > 0 {
+		return fmt.Errorf(`task: Including Taskfiles is only available starting on Taskfile version v2.2`)
+	}
+	if v >= 3.0 && e.Taskfile.Expansions > 2 {
+		return fmt.Errorf(`task: The "expansions" setting is not available anymore on v3.0`)
+	}
+
+	if e.OutputStyle != "" {
+		e.Taskfile.Output = e.OutputStyle
+	}
+	switch e.Taskfile.Output {
+	case "", "interleaved":
+		e.Output = output.Interleaved{}
+	case "group":
+		e.Output = output.Group{}
+	case "prefixed":
+		e.Output = output.Prefixed{}
+	default:
+		return fmt.Errorf(`task: output option "%s" not recognized`, e.Taskfile.Output)
+	}
+
+	if e.Taskfile.Method == "" {
+		if v >= 3 {
+			e.Taskfile.Method = "checksum"
+		} else {
+			e.Taskfile.Method = "timestamp"
+		}
+	}
+
+	if v <= 2.1 {
+		err := errors.New(`task: Taskfile option "ignore_error" is only available starting on Taskfile version v2.1`)
+
+		for _, task := range e.Taskfile.Tasks {
+			if task.IgnoreError {
+				return err
+			}
+			for _, cmd := range task.Cmds {
+				if cmd.IgnoreError {
+					return err
+				}
+			}
+		}
+	}
+
+	if v < 2.6 {
+		for _, task := range e.Taskfile.Tasks {
+			if len(task.Preconditions) > 0 {
+				return errors.New(`task: Task option "preconditions" is only available starting on Taskfile version v2.6`)
+			}
+		}
+	}
+
+	if v < 3 {
+		err := e.Taskfile.Includes.Range(func(_ string, taskfile taskfile.IncludedTaskfile) error {
+			if taskfile.AdvancedImport {
+				return errors.New(`task: Import with additional parameters is only available starting on Taskfile version v3`)
+			}
+			return nil
+		})
+		if err != nil {
+			return err
+		}
+	}
+
+	e.taskCallCount = make(map[string]*int32, len(e.Taskfile.Tasks))
+	e.mkdirMutexMap = make(map[string]*sync.Mutex, len(e.Taskfile.Tasks))
+	for k := range e.Taskfile.Tasks {
+		e.taskCallCount[k] = new(int32)
+		e.mkdirMutexMap[k] = &sync.Mutex{}
+	}
+
+	if e.Concurrency > 0 {
+		e.concurrencySemaphore = make(chan struct{}, e.Concurrency)
+	}
+	return nil
+}
+
+// RunTask runs a task by its name
+func (e *Executor) RunTask(ctx context.Context, call taskfile.Call) error {
+	t, err := e.CompiledTask(call)
+	if err != nil {
+		return err
+	}
+	if !e.Watch && atomic.AddInt32(e.taskCallCount[call.Task], 1) >= MaximumTaskCall {
+		return &MaximumTaskCallExceededError{task: call.Task}
+	}
+
+	release := e.acquireConcurrencyLimit()
+	defer release()
+
+	if err := e.runDeps(ctx, t); err != nil {
+		return err
+	}
+
+	if !e.Force {
+		preCondMet, err := e.areTaskPreconditionsMet(ctx, t)
+		if err != nil {
+			return err
+		}
+
+		upToDate, err := e.isTaskUpToDate(ctx, t)
+		if err != nil {
+			return err
+		}
+
+		if upToDate && preCondMet {
+			if !e.Silent {
+				e.Logger.Errf(logger.Magenta, `task: Task "%s" is up to date`, t.Name())
+			}
+			return nil
+		}
+	}
+
+	if err := e.mkdir(t); err != nil {
+		e.Logger.Errf(logger.Red, "task: cannot make directory %q: %v", t.Dir, err)
+	}
+
+	for i := range t.Cmds {
+		if err := e.runCommand(ctx, t, call, i); err != nil {
+			if err2 := e.statusOnError(t); err2 != nil {
+				e.Logger.VerboseErrf(logger.Yellow, "task: error cleaning status on error: %v", err2)
+			}
+
+			if execext.IsExitError(err) && t.IgnoreError {
+				e.Logger.VerboseErrf(logger.Yellow, "task: task error ignored: %v", err)
+				continue
+			}
+
+			return &taskRunError{t.Task, err}
 		}
 	}
 	return nil
 }
 
-func isTaskUpToDate(t *Task) bool {
-	if len(t.Sources) == 0 || len(t.Generates) == 0 {
-		return false
+func (e *Executor) mkdir(t *taskfile.Task) error {
+	if t.Dir == "" {
+		return nil
 	}
 
-	sourcesMaxTime, err := getPatternsMaxTime(t.Sources)
-	if err != nil || sourcesMaxTime.IsZero() {
-		return false
-	}
+	mutex := e.mkdirMutexMap[t.Task]
+	mutex.Lock()
+	defer mutex.Unlock()
 
-	generatesMinTime, err := getPatternsMinTime(t.Generates)
-	if err != nil || generatesMinTime.IsZero() {
-		return false
-	}
-
-	return generatesMinTime.After(sourcesMaxTime)
-}
-
-func runCommand(c string) error {
-	var cmd *exec.Cmd
-	if ShExists {
-		cmd = exec.Command(ShPath, "-c", c)
-	} else {
-		cmd = exec.Command("cmd", "/C", c)
-	}
-	cmd.Stdout = os.Stdout
-	cmd.Stderr = os.Stderr
-	if err := cmd.Run(); err != nil {
-		return err
+	if _, err := os.Stat(t.Dir); os.IsNotExist(err) {
+		if err := os.MkdirAll(t.Dir, 0755); err != nil {
+			return err
+		}
 	}
 	return nil
 }
+
+func (e *Executor) runDeps(ctx context.Context, t *taskfile.Task) error {
+	g, ctx := errgroup.WithContext(ctx)
+
+	reacquire := e.releaseConcurrencyLimit()
+	defer reacquire()
+
+	for _, d := range t.Deps {
+		d := d
+
+		g.Go(func() error {
+			err := e.RunTask(ctx, taskfile.Call{Task: d.Task, Vars: d.Vars})
+			if err != nil {
+				return err
+			}
+			return nil
+		})
+	}
+
+	return g.Wait()
+}
+
+func (e *Executor) runCommand(ctx context.Context, t *taskfile.Task, call taskfile.Call, i int) error {
+	cmd := t.Cmds[i]
+
+	switch {
+	case cmd.Task != "":
+		reacquire := e.releaseConcurrencyLimit()
+		defer reacquire()
+
+		err := e.RunTask(ctx, taskfile.Call{Task: cmd.Task, Vars: cmd.Vars})
+		if err != nil {
+			return err
+		}
+		return nil
+	case cmd.Cmd != "":
+		if e.Verbose || (!cmd.Silent && !t.Silent && !e.Taskfile.Silent && !e.Silent) {
+			e.Logger.Errf(logger.Green, "task: %s", cmd.Cmd)
+		}
+
+		if e.Dry {
+			return nil
+		}
+
+		stdOut := e.Output.WrapWriter(e.Stdout, t.Prefix)
+		stdErr := e.Output.WrapWriter(e.Stderr, t.Prefix)
+		defer func() {
+			if _, ok := stdOut.(*os.File); !ok {
+				if closer, ok := stdOut.(io.Closer); ok {
+					closer.Close()
+				}
+			}
+			if _, ok := stdErr.(*os.File); !ok {
+				if closer, ok := stdErr.(io.Closer); ok {
+					closer.Close()
+				}
+			}
+		}()
+
+		err := execext.RunCommand(ctx, &execext.RunCommandOptions{
+			Command: cmd.Cmd,
+			Dir:     t.Dir,
+			Env:     getEnviron(t),
+			Stdin:   e.Stdin,
+			Stdout:  stdOut,
+			Stderr:  stdErr,
+		})
+		if execext.IsExitError(err) && cmd.IgnoreError {
+			e.Logger.VerboseErrf(logger.Yellow, "task: command error ignored: %v", err)
+			return nil
+		}
+		return err
+	default:
+		return nil
+	}
+}
+
+func getEnviron(t *taskfile.Task) []string {
+	if t.Env == nil {
+		return nil
+	}
+
+	environ := os.Environ()
+
+	for k, v := range t.Env.ToCacheMap() {
+		str, isString := v.(string)
+		if !isString {
+			continue
+		}
+
+		if _, alreadySet := os.LookupEnv(k); alreadySet {
+			continue
+		}
+
+		environ = append(environ, fmt.Sprintf("%s=%s", k, str))
+	}
+
+	return environ
+}

task_test.go

@@ -0,0 +1,917 @@
+package task_test
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"github.com/go-task/task/v3"
+	"github.com/go-task/task/v3/taskfile"
+)
+
+// fileContentTest provides a basic reusable test-case for running a Taskfile
+// and inspect generated files.
+type fileContentTest struct {
+	Dir       string
+	Target    string
+	TrimSpace bool
+	Files     map[string]string
+}
+
+func (fct fileContentTest) name(file string) string {
+	return fmt.Sprintf("target=%q,file=%q", fct.Target, file)
+}
+
+func (fct fileContentTest) Run(t *testing.T) {
+	for f := range fct.Files {
+		_ = os.Remove(filepath.Join(fct.Dir, f))
+	}
+
+	e := &task.Executor{
+		Dir:    fct.Dir,
+		Stdout: ioutil.Discard,
+		Stderr: ioutil.Discard,
+	}
+	assert.NoError(t, e.Setup(), "e.Setup()")
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: fct.Target}), "e.Run(target)")
+
+	for name, expectContent := range fct.Files {
+		t.Run(fct.name(name), func(t *testing.T) {
+			b, err := ioutil.ReadFile(filepath.Join(fct.Dir, name))
+			assert.NoError(t, err, "Error reading file")
+			s := string(b)
+			if fct.TrimSpace {
+				s = strings.TrimSpace(s)
+			}
+			assert.Equal(t, expectContent, s, "unexpected file content")
+		})
+	}
+}
+
+func TestEmptyTask(t *testing.T) {
+	e := &task.Executor{
+		Dir:    "testdata/empty_task",
+		Stdout: ioutil.Discard,
+		Stderr: ioutil.Discard,
+	}
+	assert.NoError(t, e.Setup(), "e.Setup()")
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "default"}))
+}
+
+func TestEnv(t *testing.T) {
+	tt := fileContentTest{
+		Dir:       "testdata/env",
+		Target:    "default",
+		TrimSpace: false,
+		Files: map[string]string{
+			"local.txt":  "GOOS='linux' GOARCH='amd64' CGO_ENABLED='0'\n",
+			"global.txt": "FOO='foo' BAR='overriden' BAZ='baz'\n",
+		},
+	}
+	tt.Run(t)
+}
+
+func TestVarsV2(t *testing.T) {
+	tt := fileContentTest{
+		Dir:       "testdata/vars/v2",
+		Target:    "default",
+		TrimSpace: true,
+		Files: map[string]string{
+			"foo.txt":              "foo",
+			"bar.txt":              "bar",
+			"baz.txt":              "baz",
+			"tmpl_foo.txt":         "foo",
+			"tmpl_bar.txt":         "bar",
+			"tmpl_foo2.txt":        "foo2",
+			"tmpl_bar2.txt":        "bar2",
+			"shtmpl_foo.txt":       "foo",
+			"shtmpl_foo2.txt":      "foo2",
+			"nestedtmpl_foo.txt":   "<no value>",
+			"nestedtmpl_foo2.txt":  "foo2",
+			"foo2.txt":             "foo2",
+			"bar2.txt":             "bar2",
+			"baz2.txt":             "baz2",
+			"tmpl2_foo.txt":        "<no value>",
+			"tmpl2_foo2.txt":       "foo2",
+			"tmpl2_bar.txt":        "<no value>",
+			"tmpl2_bar2.txt":       "bar2",
+			"shtmpl2_foo.txt":      "<no value>",
+			"shtmpl2_foo2.txt":     "foo2",
+			"nestedtmpl2_foo2.txt": "<no value>",
+			"override.txt":         "bar",
+			"nested.txt":           "Taskvars-TaskfileVars-TaskVars",
+			"task_name.txt":        "hello",
+		},
+	}
+	tt.Run(t)
+	// Ensure identical results when running hello task directly.
+	tt.Target = "hello"
+	tt.Run(t)
+}
+
+func TestVarsV3(t *testing.T) {
+	tt := fileContentTest{
+		Dir:    "testdata/vars/v3",
+		Target: "default",
+		Files: map[string]string{
+			"missing-var.txt":  "\n",
+			"var-order.txt":    "ABCDEF\n",
+			"dependent-sh.txt": "123456\n",
+			"with-call.txt":    "Hi, ABC123!\n",
+			"from-dot-env.txt": "From .env file\n",
+		},
+	}
+	tt.Run(t)
+}
+
+func TestMultilineVars(t *testing.T) {
+	for _, dir := range []string{"testdata/vars/v2/multiline"} {
+		tt := fileContentTest{
+			Dir:       dir,
+			Target:    "default",
+			TrimSpace: false,
+			Files: map[string]string{
+				// Note:
+				// - task does not strip a trailing newline from var entries
+				// - task strips one trailing newline from shell output
+				// - the cat command adds a trailing newline
+				"echo_foobar.txt":      "foo\nbar\n",
+				"echo_n_foobar.txt":    "foo\nbar\n",
+				"echo_n_multiline.txt": "\n\nfoo\n  bar\nfoobar\n\nbaz\n\n",
+				"var_multiline.txt":    "\n\nfoo\n  bar\nfoobar\n\nbaz\n\n\n",
+				"var_catlines.txt":     "  foo   bar foobar  baz  \n",
+				"var_enumfile.txt":     "0:\n1:\n2:foo\n3:  bar\n4:foobar\n5:\n6:baz\n7:\n8:\n",
+			},
+		}
+		tt.Run(t)
+	}
+}
+
+func TestVarsInvalidTmpl(t *testing.T) {
+	const (
+		dir         = "testdata/vars/v2"
+		target      = "invalid-var-tmpl"
+		expectError = "template: :1: unexpected EOF"
+	)
+
+	e := &task.Executor{
+		Dir:    dir,
+		Stdout: ioutil.Discard,
+		Stderr: ioutil.Discard,
+	}
+	assert.NoError(t, e.Setup(), "e.Setup()")
+	assert.EqualError(t, e.Run(context.Background(), taskfile.Call{Task: target}), expectError, "e.Run(target)")
+}
+
+func TestConcurrency(t *testing.T) {
+	const (
+		dir    = "testdata/concurrency"
+		target = "default"
+	)
+
+	e := &task.Executor{
+		Dir:         dir,
+		Stdout:      ioutil.Discard,
+		Stderr:      ioutil.Discard,
+		Concurrency: 1,
+	}
+	assert.NoError(t, e.Setup(), "e.Setup()")
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: target}), "e.Run(target)")
+}
+
+func TestParams(t *testing.T) {
+	tt := fileContentTest{
+		Dir:       "testdata/params",
+		Target:    "default",
+		TrimSpace: false,
+		Files: map[string]string{
+			"hello.txt":       "Hello\n",
+			"world.txt":       "World\n",
+			"exclamation.txt": "!\n",
+			"dep1.txt":        "Dependence1\n",
+			"dep2.txt":        "Dependence2\n",
+			"spanish.txt":     "¡Holla mundo!\n",
+			"spanish-dep.txt": "¡Holla dependencia!\n",
+			"portuguese.txt":  "Olá, mundo!\n",
+			"portuguese2.txt": "Olá, mundo!\n",
+			"german.txt":      "Welt!\n",
+		},
+	}
+	tt.Run(t)
+}
+
+func TestDeps(t *testing.T) {
+	const dir = "testdata/deps"
+
+	files := []string{
+		"d1.txt",
+		"d2.txt",
+		"d3.txt",
+		"d11.txt",
+		"d12.txt",
+		"d13.txt",
+		"d21.txt",
+		"d22.txt",
+		"d23.txt",
+		"d31.txt",
+		"d32.txt",
+		"d33.txt",
+	}
+
+	for _, f := range files {
+		_ = os.Remove(filepath.Join(dir, f))
+	}
+
+	e := &task.Executor{
+		Dir:    dir,
+		Stdout: ioutil.Discard,
+		Stderr: ioutil.Discard,
+	}
+	assert.NoError(t, e.Setup())
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "default"}))
+
+	for _, f := range files {
+		f = filepath.Join(dir, f)
+		if _, err := os.Stat(f); err != nil {
+			t.Errorf("File %s should exist", f)
+		}
+	}
+}
+
+func TestStatus(t *testing.T) {
+	const dir = "testdata/status"
+	var file = filepath.Join(dir, "foo.txt")
+
+	_ = os.Remove(file)
+
+	if _, err := os.Stat(file); err == nil {
+		t.Errorf("File should not exist: %v", err)
+	}
+
+	var buff bytes.Buffer
+	e := &task.Executor{
+		Dir:    dir,
+		Stdout: &buff,
+		Stderr: &buff,
+		Silent: true,
+	}
+	assert.NoError(t, e.Setup())
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "gen-foo"}))
+
+	if _, err := os.Stat(file); err != nil {
+		t.Errorf("File should exist: %v", err)
+	}
+
+	e.Silent = false
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "gen-foo"}))
+
+	if buff.String() != `task: Task "gen-foo" is up to date`+"\n" {
+		t.Errorf("Wrong output message: %s", buff.String())
+	}
+}
+
+func TestPrecondition(t *testing.T) {
+	const dir = "testdata/precondition"
+
+	var buff bytes.Buffer
+	e := &task.Executor{
+		Dir:    dir,
+		Stdout: &buff,
+		Stderr: &buff,
+	}
+
+	// A precondition that has been met
+	assert.NoError(t, e.Setup())
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "foo"}))
+	if buff.String() != "" {
+		t.Errorf("Got Output when none was expected: %s", buff.String())
+	}
+
+	// A precondition that was not met
+	assert.Error(t, e.Run(context.Background(), taskfile.Call{Task: "impossible"}))
+
+	if buff.String() != "task: 1 != 0 obviously!\n" {
+		t.Errorf("Wrong output message: %s", buff.String())
+	}
+	buff.Reset()
+
+	// Calling a task with a precondition in a dependency fails the task
+	assert.Error(t, e.Run(context.Background(), taskfile.Call{Task: "depends_on_impossible"}))
+
+	if buff.String() != "task: 1 != 0 obviously!\n" {
+		t.Errorf("Wrong output message: %s", buff.String())
+	}
+	buff.Reset()
+
+	// Calling a task with a precondition in a cmd fails the task
+	assert.Error(t, e.Run(context.Background(), taskfile.Call{Task: "executes_failing_task_as_cmd"}))
+	if buff.String() != "task: 1 != 0 obviously!\n" {
+		t.Errorf("Wrong output message: %s", buff.String())
+	}
+	buff.Reset()
+}
+
+func TestGenerates(t *testing.T) {
+	const dir = "testdata/generates"
+
+	const (
+		srcTask        = "sub/src.txt"
+		relTask        = "rel.txt"
+		absTask        = "abs.txt"
+		fileWithSpaces = "my text file.txt"
+	)
+
+	var srcFile = filepath.Join(dir, srcTask)
+
+	for _, task := range []string{srcTask, relTask, absTask, fileWithSpaces} {
+		path := filepath.Join(dir, task)
+		_ = os.Remove(path)
+		if _, err := os.Stat(path); err == nil {
+			t.Errorf("File should not exist: %v", err)
+		}
+	}
+
+	buff := bytes.NewBuffer(nil)
+	e := &task.Executor{
+		Dir:    dir,
+		Stdout: buff,
+		Stderr: buff,
+	}
+	assert.NoError(t, e.Setup())
+
+	for _, theTask := range []string{relTask, absTask, fileWithSpaces} {
+		var destFile = filepath.Join(dir, theTask)
+		var upToDate = fmt.Sprintf("task: Task \"%s\" is up to date\n", srcTask) +
+			fmt.Sprintf("task: Task \"%s\" is up to date\n", theTask)
+
+		// Run task for the first time.
+		assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: theTask}))
+
+		if _, err := os.Stat(srcFile); err != nil {
+			t.Errorf("File should exist: %v", err)
+		}
+		if _, err := os.Stat(destFile); err != nil {
+			t.Errorf("File should exist: %v", err)
+		}
+		// Ensure task was not incorrectly found to be up-to-date on first run.
+		if buff.String() == upToDate {
+			t.Errorf("Wrong output message: %s", buff.String())
+		}
+		buff.Reset()
+
+		// Re-run task to ensure it's now found to be up-to-date.
+		assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: theTask}))
+		if buff.String() != upToDate {
+			t.Errorf("Wrong output message: %s", buff.String())
+		}
+		buff.Reset()
+	}
+}
+
+func TestStatusChecksum(t *testing.T) {
+	const dir = "testdata/checksum"
+
+	files := []string{
+		"generated.txt",
+		".task/checksum/build",
+	}
+
+	for _, f := range files {
+		_ = os.Remove(filepath.Join(dir, f))
+
+		_, err := os.Stat(filepath.Join(dir, f))
+		assert.Error(t, err)
+	}
+
+	var buff bytes.Buffer
+	e := task.Executor{
+		Dir:    dir,
+		Stdout: &buff,
+		Stderr: &buff,
+	}
+	assert.NoError(t, e.Setup())
+
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "build"}))
+	for _, f := range files {
+		_, err := os.Stat(filepath.Join(dir, f))
+		assert.NoError(t, err)
+	}
+
+	buff.Reset()
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "build"}))
+	assert.Equal(t, `task: Task "build" is up to date`+"\n", buff.String())
+}
+
+func TestLabelUpToDate(t *testing.T) {
+	const dir = "testdata/label_uptodate"
+
+	var buff bytes.Buffer
+	e := task.Executor{
+		Dir:    dir,
+		Stdout: &buff,
+		Stderr: &buff,
+	}
+	assert.NoError(t, e.Setup())
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "foo"}))
+	assert.Contains(t, buff.String(), "foobar")
+}
+
+func TestLabelSummary(t *testing.T) {
+	const dir = "testdata/label_summary"
+
+	var buff bytes.Buffer
+	e := task.Executor{
+		Dir:     dir,
+		Summary: true,
+		Stdout:  &buff,
+		Stderr:  &buff,
+	}
+	assert.NoError(t, e.Setup())
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "foo"}))
+	assert.Contains(t, buff.String(), "foobar")
+}
+
+func TestLabelInStatus(t *testing.T) {
+	const dir = "testdata/label_status"
+
+	e := task.Executor{
+		Dir: dir,
+	}
+	assert.NoError(t, e.Setup())
+	err := e.Status(context.Background(), taskfile.Call{Task: "foo"})
+	if assert.Error(t, err) {
+		assert.Contains(t, err.Error(), "foobar")
+	}
+}
+
+func TestLabelWithVariableExpansion(t *testing.T) {
+	const dir = "testdata/label_var"
+
+	var buff bytes.Buffer
+	e := task.Executor{
+		Dir:    dir,
+		Stdout: &buff,
+		Stderr: &buff,
+	}
+	assert.NoError(t, e.Setup())
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "foo"}))
+	assert.Contains(t, buff.String(), "foobaz")
+}
+
+func TestLabelInSummary(t *testing.T) {
+	const dir = "testdata/label_summary"
+
+	var buff bytes.Buffer
+	e := task.Executor{
+		Dir:    dir,
+		Stdout: &buff,
+		Stderr: &buff,
+	}
+	assert.NoError(t, e.Setup())
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "foo"}))
+	assert.Contains(t, buff.String(), "foobar")
+}
+
+func TestLabelInList(t *testing.T) {
+	const dir = "testdata/label_list"
+
+	var buff bytes.Buffer
+	e := task.Executor{
+		Dir:    dir,
+		Stdout: &buff,
+		Stderr: &buff,
+	}
+	assert.NoError(t, e.Setup())
+	e.PrintTasksHelp()
+	assert.Contains(t, buff.String(), "foobar")
+}
+
+func TestStatusVariables(t *testing.T) {
+	const dir = "testdata/status_vars"
+
+	_ = os.RemoveAll(filepath.Join(dir, ".task"))
+	_ = os.Remove(filepath.Join(dir, "generated.txt"))
+
+	var buff bytes.Buffer
+	e := task.Executor{
+		Dir:     dir,
+		Stdout:  &buff,
+		Stderr:  &buff,
+		Silent:  false,
+		Verbose: true,
+	}
+	assert.NoError(t, e.Setup())
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "build"}))
+
+	assert.Contains(t, buff.String(), "d41d8cd98f00b204e9800998ecf8427e")
+
+	inf, err := os.Stat(filepath.Join(dir, "source.txt"))
+	assert.NoError(t, err)
+	ts := fmt.Sprintf("%d", inf.ModTime().Unix())
+	tf := fmt.Sprintf("%s", inf.ModTime())
+
+	assert.Contains(t, buff.String(), ts)
+	assert.Contains(t, buff.String(), tf)
+}
+
+func TestInit(t *testing.T) {
+	const dir = "testdata/init"
+	var file = filepath.Join(dir, "Taskfile.yml")
+
+	_ = os.Remove(file)
+	if _, err := os.Stat(file); err == nil {
+		t.Errorf("Taskfile.yml should not exist")
+	}
+
+	if err := task.InitTaskfile(ioutil.Discard, dir); err != nil {
+		t.Error(err)
+	}
+
+	if _, err := os.Stat(file); err != nil {
+		t.Errorf("Taskfile.yml should exist")
+	}
+}
+
+func TestCyclicDep(t *testing.T) {
+	const dir = "testdata/cyclic"
+
+	e := task.Executor{
+		Dir:    dir,
+		Stdout: ioutil.Discard,
+		Stderr: ioutil.Discard,
+	}
+	assert.NoError(t, e.Setup())
+	assert.IsType(t, &task.MaximumTaskCallExceededError{}, e.Run(context.Background(), taskfile.Call{Task: "task-1"}))
+}
+
+func TestTaskVersion(t *testing.T) {
+	tests := []struct {
+		Dir     string
+		Version string
+	}{
+		{"testdata/version/v2", "2"},
+	}
+
+	for _, test := range tests {
+		t.Run(test.Dir, func(t *testing.T) {
+			e := task.Executor{
+				Dir:    test.Dir,
+				Stdout: ioutil.Discard,
+				Stderr: ioutil.Discard,
+			}
+			assert.NoError(t, e.Setup())
+			assert.Equal(t, test.Version, e.Taskfile.Version)
+			assert.Equal(t, 2, len(e.Taskfile.Tasks))
+		})
+	}
+}
+
+func TestTaskIgnoreErrors(t *testing.T) {
+	const dir = "testdata/ignore_errors"
+
+	e := task.Executor{
+		Dir:    dir,
+		Stdout: ioutil.Discard,
+		Stderr: ioutil.Discard,
+	}
+	assert.NoError(t, e.Setup())
+
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "task-should-pass"}))
+	assert.Error(t, e.Run(context.Background(), taskfile.Call{Task: "task-should-fail"}))
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "cmd-should-pass"}))
+	assert.Error(t, e.Run(context.Background(), taskfile.Call{Task: "cmd-should-fail"}))
+}
+
+func TestExpand(t *testing.T) {
+	const dir = "testdata/expand"
+
+	home, err := os.UserHomeDir()
+	if err != nil {
+		t.Errorf("Couldn't get $HOME: %v", err)
+	}
+	var buff bytes.Buffer
+
+	e := task.Executor{
+		Dir:    dir,
+		Stdout: &buff,
+		Stderr: &buff,
+	}
+	assert.NoError(t, e.Setup())
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "pwd"}))
+	assert.Equal(t, home, strings.TrimSpace(buff.String()))
+}
+
+func TestDry(t *testing.T) {
+	const dir = "testdata/dry"
+
+	file := filepath.Join(dir, "file.txt")
+	_ = os.Remove(file)
+
+	var buff bytes.Buffer
+
+	e := task.Executor{
+		Dir:    dir,
+		Stdout: &buff,
+		Stderr: &buff,
+		Dry:    true,
+	}
+	assert.NoError(t, e.Setup())
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "build"}))
+
+	assert.Equal(t, "task: touch file.txt", strings.TrimSpace(buff.String()))
+	if _, err := os.Stat(file); err == nil {
+		t.Errorf("File should not exist %s", file)
+	}
+}
+
+// TestDryChecksum tests if the checksum file is not being written to disk
+// if the dry mode is enabled.
+func TestDryChecksum(t *testing.T) {
+	const dir = "testdata/dry_checksum"
+
+	checksumFile := filepath.Join(dir, ".task/checksum/default")
+	_ = os.Remove(checksumFile)
+
+	e := task.Executor{
+		Dir:    dir,
+		Stdout: ioutil.Discard,
+		Stderr: ioutil.Discard,
+		Dry:    true,
+	}
+	assert.NoError(t, e.Setup())
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "default"}))
+
+	_, err := os.Stat(checksumFile)
+	assert.Error(t, err, "checksum file should not exist")
+
+	e.Dry = false
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "default"}))
+	_, err = os.Stat(checksumFile)
+	assert.NoError(t, err, "checksum file should exist")
+}
+
+func TestIncludes(t *testing.T) {
+	tt := fileContentTest{
+		Dir:       "testdata/includes",
+		Target:    "default",
+		TrimSpace: true,
+		Files: map[string]string{
+			"main.txt":                                  "main",
+			"included_directory.txt":                    "included_directory",
+			"included_directory_without_dir.txt":        "included_directory_without_dir",
+			"included_taskfile_without_dir.txt":         "included_taskfile_without_dir",
+			"./module2/included_directory_with_dir.txt": "included_directory_with_dir",
+			"./module2/included_taskfile_with_dir.txt":  "included_taskfile_with_dir",
+			"os_include.txt":                            "os",
+		},
+	}
+	tt.Run(t)
+}
+
+func TestIncorrectVersionIncludes(t *testing.T) {
+	const dir = "testdata/incorrect_includes"
+	expectedError := "task: Import with additional parameters is only available starting on Taskfile version v3"
+
+	var buff bytes.Buffer
+	e := task.Executor{
+		Dir:    dir,
+		Stdout: &buff,
+		Stderr: &buff,
+		Silent: true,
+	}
+
+	assert.EqualError(t, e.Setup(), expectedError)
+}
+
+func TestIncludesEmptyMain(t *testing.T) {
+	tt := fileContentTest{
+		Dir:       "testdata/includes_empty",
+		Target:    "included:default",
+		TrimSpace: true,
+		Files: map[string]string{
+			"file.txt": "default",
+		},
+	}
+	tt.Run(t)
+}
+
+func TestIncludesDependencies(t *testing.T) {
+	tt := fileContentTest{
+		Dir:       "testdata/includes_deps",
+		Target:    "default",
+		TrimSpace: true,
+		Files: map[string]string{
+			"default.txt":     "default",
+			"called_dep.txt":  "called_dep",
+			"called_task.txt": "called_task",
+		},
+	}
+	tt.Run(t)
+}
+
+func TestIncludesCallingRoot(t *testing.T) {
+	tt := fileContentTest{
+		Dir:       "testdata/includes_call_root_task",
+		Target:    "included:call-root",
+		TrimSpace: true,
+		Files: map[string]string{
+			"root_task.txt": "root task",
+		},
+	}
+	tt.Run(t)
+}
+
+func TestSummary(t *testing.T) {
+	const dir = "testdata/summary"
+
+	var buff bytes.Buffer
+	e := task.Executor{
+		Dir:     dir,
+		Stdout:  &buff,
+		Stderr:  &buff,
+		Summary: true,
+		Silent:  true,
+	}
+	assert.NoError(t, e.Setup())
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "task-with-summary"}, taskfile.Call{Task: "other-task-with-summary"}))
+
+	data, err := ioutil.ReadFile(filepath.Join(dir, "task-with-summary.txt"))
+	assert.NoError(t, err)
+
+	expectedOutput := string(data)
+	if runtime.GOOS == "windows" {
+		expectedOutput = strings.Replace(expectedOutput, "\r\n", "\n", -1)
+	}
+
+	assert.Equal(t, expectedOutput, buff.String())
+}
+
+func TestWhenNoDirAttributeItRunsInSameDirAsTaskfile(t *testing.T) {
+	const expected = "dir"
+	const dir = "testdata/" + expected
+	var out bytes.Buffer
+	e := &task.Executor{
+		Dir:    dir,
+		Stdout: &out,
+		Stderr: &out,
+	}
+
+	assert.NoError(t, e.Setup())
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "whereami"}))
+
+	// got should be the "dir" part of "testdata/dir"
+	got := strings.TrimSuffix(filepath.Base(out.String()), "\n")
+	assert.Equal(t, expected, got, "Mismatch in the working directory")
+}
+
+func TestWhenDirAttributeAndDirExistsItRunsInThatDir(t *testing.T) {
+	const expected = "exists"
+	const dir = "testdata/dir/explicit_exists"
+	var out bytes.Buffer
+	e := &task.Executor{
+		Dir:    dir,
+		Stdout: &out,
+		Stderr: &out,
+	}
+
+	assert.NoError(t, e.Setup())
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "whereami"}))
+
+	got := strings.TrimSuffix(filepath.Base(out.String()), "\n")
+	assert.Equal(t, expected, got, "Mismatch in the working directory")
+}
+
+func TestWhenDirAttributeItCreatesMissingAndRunsInThatDir(t *testing.T) {
+	const expected = "createme"
+	const dir = "testdata/dir/explicit_doesnt_exist/"
+	const toBeCreated = dir + expected
+	const target = "whereami"
+	var out bytes.Buffer
+	e := &task.Executor{
+		Dir:    dir,
+		Stdout: &out,
+		Stderr: &out,
+	}
+
+	// Ensure that the directory to be created doesn't actually exist.
+	_ = os.RemoveAll(toBeCreated)
+	if _, err := os.Stat(toBeCreated); err == nil {
+		t.Errorf("Directory should not exist: %v", err)
+	}
+	assert.NoError(t, e.Setup())
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: target}))
+
+	got := strings.TrimSuffix(filepath.Base(out.String()), "\n")
+	assert.Equal(t, expected, got, "Mismatch in the working directory")
+
+	// Clean-up after ourselves only if no error.
+	_ = os.RemoveAll(toBeCreated)
+}
+
+func TestDynamicVariablesShouldRunOnTheTaskDir(t *testing.T) {
+	tt := fileContentTest{
+		Dir:       "testdata/dir/dynamic_var",
+		Target:    "default",
+		TrimSpace: false,
+		Files: map[string]string{
+			"subdirectory/from_root_taskfile.txt":          "subdirectory\n",
+			"subdirectory/from_included_taskfile.txt":      "subdirectory\n",
+			"subdirectory/from_included_taskfile_task.txt": "subdirectory\n",
+			"subdirectory/from_interpolated_dir.txt":       "subdirectory\n",
+		},
+	}
+	tt.Run(t)
+}
+
+func TestDisplaysErrorOnUnsupportedVersion(t *testing.T) {
+	e := task.Executor{
+		Dir:    "testdata/version/v1",
+		Stdout: ioutil.Discard,
+		Stderr: ioutil.Discard,
+	}
+	err := e.Setup()
+	assert.Error(t, err)
+	assert.Equal(t, "task: Taskfile versions prior to v2 are not supported anymore", err.Error())
+
+}
+
+func TestShortTaskNotation(t *testing.T) {
+	const dir = "testdata/short_task_notation"
+
+	var buff bytes.Buffer
+	e := task.Executor{
+		Dir:    dir,
+		Stdout: &buff,
+		Stderr: &buff,
+		Silent: true,
+	}
+	assert.NoError(t, e.Setup())
+	assert.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "default"}))
+	assert.Equal(t, "string-slice-1\nstring-slice-2\nstring\n", buff.String())
+}
+
+func TestDotenvShouldIncludeAllEnvFiles(t *testing.T) {
+	tt := fileContentTest{
+		Dir:       "testdata/dotenv/default",
+		Target:    "default",
+		TrimSpace: false,
+		Files: map[string]string{
+			"include.txt": "INCLUDE1='from_include1' INCLUDE2='from_include2'\n",
+		},
+	}
+	tt.Run(t)
+}
+
+func TestDotenvShouldErrorWhenIncludingDependantDotenvs(t *testing.T) {
+	const dir = "testdata/dotenv/error_included_envs"
+	const entry = "Taskfile.yml"
+
+	var buff bytes.Buffer
+	e := task.Executor{
+		Dir:        dir,
+		Entrypoint: entry,
+		Summary:    true,
+		Stdout:     &buff,
+		Stderr:     &buff,
+	}
+
+	err := e.Setup()
+	assert.Error(t, err)
+	assert.Contains(t, err.Error(), "move the dotenv")
+}
+
+func TestDotenvShouldAllowMissingEnv(t *testing.T) {
+	tt := fileContentTest{
+		Dir:       "testdata/dotenv/missing_env",
+		Target:    "default",
+		TrimSpace: false,
+		Files: map[string]string{
+			"include.txt": "INCLUDE1='' INCLUDE2=''\n",
+		},
+	}
+	tt.Run(t)
+}
+
+func TestExitImmediately(t *testing.T) {
+	const dir = "testdata/exit_immediately"
+
+	var buff bytes.Buffer
+	e := task.Executor{
+		Dir:    dir,
+		Stdout: &buff,
+		Stderr: &buff,
+		Silent: true,
+	}
+	assert.NoError(t, e.Setup())
+
+	assert.Error(t, e.Run(context.Background(), taskfile.Call{Task: "default"}))
+	assert.Contains(t, buff.String(), `"this_should_fail": executable file not found in $PATH`)
+}

taskfile/call.go

@@ -0,0 +1,7 @@
+package taskfile
+
+// Call is the parameters to a task call
+type Call struct {
+	Task string
+	Vars *Vars
+}

taskfile/cmd.go

@@ -0,0 +1,81 @@
+package taskfile
+
+import (
+	"errors"
+	"strings"
+)
+
+// Cmd is a task command
+type Cmd struct {
+	Cmd         string
+	Silent      bool
+	Task        string
+	Vars        *Vars
+	IgnoreError bool
+}
+
+// Dep is a task dependency
+type Dep struct {
+	Task string
+	Vars *Vars
+}
+
+var (
+	// ErrCantUnmarshalCmd is returned for invalid command YAML
+	ErrCantUnmarshalCmd = errors.New("task: can't unmarshal cmd value")
+	// ErrCantUnmarshalDep is returned for invalid dependency YAML
+	ErrCantUnmarshalDep = errors.New("task: can't unmarshal dep value")
+)
+
+// UnmarshalYAML implements yaml.Unmarshaler interface
+func (c *Cmd) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var cmd string
+	if err := unmarshal(&cmd); err == nil {
+		if strings.HasPrefix(cmd, "^") {
+			c.Task = strings.TrimPrefix(cmd, "^")
+		} else {
+			c.Cmd = cmd
+		}
+		return nil
+	}
+	var cmdStruct struct {
+		Cmd         string
+		Silent      bool
+		IgnoreError bool `yaml:"ignore_error"`
+	}
+	if err := unmarshal(&cmdStruct); err == nil && cmdStruct.Cmd != "" {
+		c.Cmd = cmdStruct.Cmd
+		c.Silent = cmdStruct.Silent
+		c.IgnoreError = cmdStruct.IgnoreError
+		return nil
+	}
+	var taskCall struct {
+		Task string
+		Vars *Vars
+	}
+	if err := unmarshal(&taskCall); err == nil {
+		c.Task = taskCall.Task
+		c.Vars = taskCall.Vars
+		return nil
+	}
+	return ErrCantUnmarshalCmd
+}
+
+// UnmarshalYAML implements yaml.Unmarshaler interface
+func (d *Dep) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var task string
+	if err := unmarshal(&task); err == nil {
+		d.Task = task
+		return nil
+	}
+	var taskCall struct {
+		Task string
+		Vars *Vars
+	}
+	if err := unmarshal(&taskCall); err == nil {
+		d.Task = taskCall.Task
+		d.Vars = taskCall.Vars
+		return nil
+	}
+	return ErrCantUnmarshalDep
+}

taskfile/included_taskfile.go

@@ -0,0 +1,109 @@
+package taskfile
+
+import (
+	"errors"
+
+	"gopkg.in/yaml.v3"
+)
+
+var (
+	// ErrCantUnmarshalIncludedTaskfile is returned for invalid var YAML.
+	ErrCantUnmarshalIncludedTaskfile = errors.New("task: can't unmarshal included value")
+)
+
+// IncludedTaskfile represents information about included tasksfile
+type IncludedTaskfile struct {
+	Taskfile       string
+	Dir            string
+	AdvancedImport bool
+}
+
+// IncludedTaskfiles represents information about included tasksfiles
+type IncludedTaskfiles struct {
+	Keys    []string
+	Mapping map[string]IncludedTaskfile
+}
+
+// UnmarshalYAML implements the yaml.Unmarshaler interface.
+func (tfs *IncludedTaskfiles) UnmarshalYAML(node *yaml.Node) error {
+	if node.Kind != yaml.MappingNode {
+		return errors.New("task: includes is not a map")
+	}
+
+	// NOTE(@andreynering): on this style of custom unmarsheling,
+	// even number contains the keys, while odd numbers contains
+	// the values.
+	for i := 0; i < len(node.Content); i += 2 {
+		keyNode := node.Content[i]
+		valueNode := node.Content[i+1]
+
+		var v IncludedTaskfile
+		if err := valueNode.Decode(&v); err != nil {
+			return err
+		}
+		tfs.Set(keyNode.Value, v)
+	}
+	return nil
+}
+
+// Len returns the length of the map
+func (tfs *IncludedTaskfiles) Len() int {
+	if tfs == nil {
+		return 0
+	}
+	return len(tfs.Keys)
+}
+
+// Merge merges the given IncludedTaskfiles into the caller one
+func (tfs *IncludedTaskfiles) Merge(other *IncludedTaskfiles) {
+	other.Range(func(key string, value IncludedTaskfile) error {
+		tfs.Set(key, value)
+		return nil
+	})
+}
+
+// Set sets a value to a given key
+func (tfs *IncludedTaskfiles) Set(key string, includedTaskfile IncludedTaskfile) {
+	if tfs.Mapping == nil {
+		tfs.Mapping = make(map[string]IncludedTaskfile, 1)
+	}
+	if !stringSliceContains(tfs.Keys, key) {
+		tfs.Keys = append(tfs.Keys, key)
+	}
+	tfs.Mapping[key] = includedTaskfile
+}
+
+// Range allows you to loop into the included taskfiles in its right order
+func (tfs *IncludedTaskfiles) Range(yield func(key string, includedTaskfile IncludedTaskfile) error) error {
+	if tfs == nil {
+		return nil
+	}
+	for _, k := range tfs.Keys {
+		if err := yield(k, tfs.Mapping[k]); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// UnmarshalYAML implements yaml.Unmarshaler interface
+func (it *IncludedTaskfile) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var str string
+	if err := unmarshal(&str); err == nil {
+		it.Taskfile = str
+		return nil
+	}
+
+	var includedTaskfile struct {
+		Taskfile string
+		Dir      string
+	}
+	if err := unmarshal(&includedTaskfile); err == nil {
+		it.Dir = includedTaskfile.Dir
+		it.Taskfile = includedTaskfile.Taskfile
+		it.AdvancedImport = true
+		return nil
+	}
+
+	return ErrCantUnmarshalIncludedTaskfile
+}

taskfile/merge.go

@@ -0,0 +1,66 @@
+package taskfile
+
+import (
+	"fmt"
+	"strings"
+)
+
+// NamespaceSeparator contains the character that separates namescapes
+const NamespaceSeparator = ":"
+
+// Merge merges the second Taskfile into the first
+func Merge(t1, t2 *Taskfile, namespaces ...string) error {
+	if t1.Version != t2.Version {
+		return fmt.Errorf(`Taskfiles versions should match. First is "%s" but second is "%s"`, t1.Version, t2.Version)
+	}
+
+	if t2.Expansions != 0 && t2.Expansions != 2 {
+		t1.Expansions = t2.Expansions
+	}
+	if t2.Output != "" {
+		t1.Output = t2.Output
+	}
+
+	if t1.Includes == nil {
+		t1.Includes = &IncludedTaskfiles{}
+	}
+	t1.Includes.Merge(t2.Includes)
+
+	if t1.Vars == nil {
+		t1.Vars = &Vars{}
+	}
+	if t1.Env == nil {
+		t1.Env = &Vars{}
+	}
+	t1.Vars.Merge(t2.Vars)
+	t1.Env.Merge(t2.Env)
+
+	if t1.Tasks == nil {
+		t1.Tasks = make(Tasks)
+	}
+	for k, v := range t2.Tasks {
+		// FIXME(@andreynering): Refactor this block, otherwise we can
+		// have serious side-effects in the future, since we're editing
+		// the original references instead of deep copying them.
+
+		t1.Tasks[taskNameWithNamespace(k, namespaces...)] = v
+
+		for _, dep := range v.Deps {
+			dep.Task = taskNameWithNamespace(dep.Task, namespaces...)
+		}
+		for _, cmd := range v.Cmds {
+			if cmd.Task != "" {
+				cmd.Task = taskNameWithNamespace(cmd.Task, namespaces...)
+			}
+		}
+	}
+
+	return nil
+}
+
+func taskNameWithNamespace(taskName string, namespaces ...string) string {
+	if strings.HasPrefix(taskName, ":") {
+		return strings.TrimPrefix(taskName, ":")
+	}
+	return strings.Join(append(namespaces, taskName), NamespaceSeparator)
+}

taskfile/precondition.go

@@ -0,0 +1,45 @@
+package taskfile
+
+import (
+	"errors"
+	"fmt"
+)
+
+var (
+	// ErrCantUnmarshalPrecondition is returned for invalid precond YAML.
+	ErrCantUnmarshalPrecondition = errors.New("task: Can't unmarshal precondition value")
+)
+
+// Precondition represents a precondition necessary for a task to run
+type Precondition struct {
+	Sh  string
+	Msg string
+}
+
+// UnmarshalYAML implements yaml.Unmarshaler interface.
+func (p *Precondition) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var cmd string
+
+	if err := unmarshal(&cmd); err == nil {
+		p.Sh = cmd
+		p.Msg = fmt.Sprintf("`%s` failed", cmd)
+		return nil
+	}
+
+	var sh struct {
+		Sh  string
+		Msg string
+	}
+
+	if err := unmarshal(&sh); err != nil {
+		return err
+	}
+
+	p.Sh = sh.Sh
+	p.Msg = sh.Msg
+	if p.Msg == "" {
+		p.Msg = fmt.Sprintf("%s failed", sh.Sh)
+	}
+
+	return nil
+}

taskfile/precondition_test.go

@@ -0,0 +1,48 @@
+package taskfile_test
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"gopkg.in/yaml.v3"
+
+	"github.com/go-task/task/v3/taskfile"
+)
+
+func TestPreconditionParse(t *testing.T) {
+	tests := []struct {
+		content  string
+		v        interface{}
+		expected interface{}
+	}{
+		{
+			"test -f foo.txt",
+			&taskfile.Precondition{},
+			&taskfile.Precondition{Sh: `test -f foo.txt`, Msg: "`test -f foo.txt` failed"},
+		},
+		{
+			"sh: '[ 1 = 0 ]'",
+			&taskfile.Precondition{},
+			&taskfile.Precondition{Sh: "[ 1 = 0 ]", Msg: "[ 1 = 0 ] failed"},
+		},
+		{`
+sh: "[ 1 = 2 ]"
+msg: "1 is not 2"
+`,
+			&taskfile.Precondition{},
+			&taskfile.Precondition{Sh: "[ 1 = 2 ]", Msg: "1 is not 2"},
+		},
+		{`
+sh: "[ 1 = 2 ]"
+msg: "1 is not 2"
+`,
+			&taskfile.Precondition{},
+			&taskfile.Precondition{Sh: "[ 1 = 2 ]", Msg: "1 is not 2"},
+		},
+	}
+	for _, test := range tests {
+		err := yaml.Unmarshal([]byte(test.content), test.v)
+		assert.NoError(t, err)
+		assert.Equal(t, test.expected, test.v)
+	}
+}

taskfile/read/taskfile.go

@@ -0,0 +1,158 @@
+package read
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"runtime"
+
+	"github.com/joho/godotenv"
+	"gopkg.in/yaml.v3"
+
+	"github.com/go-task/task/v3/internal/templater"
+	"github.com/go-task/task/v3/taskfile"
+)
+
+var (
+	// ErrIncludedTaskfilesCantHaveIncludes is returned when a included Taskfile contains includes
+	ErrIncludedTaskfilesCantHaveIncludes = errors.New("task: Included Taskfiles can't have includes. Please, move the include to the main Taskfile")
+	// ErrIncludedTaskfilesCantHaveDotenvs is returned when a included Taskfile contains dotenvs
+	ErrIncludedTaskfilesCantHaveDotenvs = errors.New("task: Included Taskfiles can't have dotenv declarations. Please, move the dotenv declaration to the main Taskfile")
+)
+
+// Taskfile reads a Taskfile for a given directory
+func Taskfile(dir string, entrypoint string) (*taskfile.Taskfile, error) {
+	path := filepath.Join(dir, entrypoint)
+	if _, err := os.Stat(path); err != nil {
+		return nil, fmt.Errorf(`task: No Taskfile found on "%s". Use "task --init" to create a new one`, path)
+	}
+	t, err := readTaskfile(path)
+	if err != nil {
+		return nil, err
+	}
+
+	v, err := t.ParsedVersion()
+	if err != nil {
+		return nil, err
+	}
+
+	if v >= 3.0 {
+		for _, dotEnvPath := range t.Dotenv {
+			if !filepath.IsAbs(dotEnvPath) {
+				dotEnvPath = filepath.Join(dir, dotEnvPath)
+			}
+			if _, err := os.Stat(dotEnvPath); os.IsNotExist(err) {
+				continue
+			}
+
+			envs, err := godotenv.Read(dotEnvPath)
+			if err != nil {
+				return nil, err
+			}
+			for key, value := range envs {
+				if _, ok := t.Env.Mapping[key]; !ok {
+					t.Env.Set(key, taskfile.Var{Static: value})
+				}
+			}
+		}
+	}
+
+	err = t.Includes.Range(func(namespace string, includedTask taskfile.IncludedTaskfile) error {
+		if v >= 3.0 {
+			tr := templater.Templater{Vars: &taskfile.Vars{}, RemoveNoValue: true}
+			includedTask = taskfile.IncludedTaskfile{
+				Taskfile:       tr.Replace(includedTask.Taskfile),
+				Dir:            tr.Replace(includedTask.Dir),
+				AdvancedImport: includedTask.AdvancedImport,
+			}
+			if err := tr.Err(); err != nil {
+				return err
+			}
+		}
+
+		if filepath.IsAbs(includedTask.Taskfile) {
+			path = includedTask.Taskfile
+		} else {
+			path = filepath.Join(dir, includedTask.Taskfile)
+		}
+
+		info, err := os.Stat(path)
+		if err != nil {
+			return err
+		}
+		if info.IsDir() {
+			path = filepath.Join(path, "Taskfile.yml")
+		}
+		includedTaskfile, err := readTaskfile(path)
+		if err != nil {
+			return err
+		}
+		if includedTaskfile.Includes.Len() > 0 {
+			return ErrIncludedTaskfilesCantHaveIncludes
+		}
+
+		if v >= 3.0 && len(includedTaskfile.Dotenv) > 0 {
+			return ErrIncludedTaskfilesCantHaveDotenvs
+		}
+
+		if includedTask.AdvancedImport {
+			for k, v := range includedTaskfile.Vars.Mapping {
+				o := v
+				o.Dir = filepath.Join(dir, includedTask.Dir)
+				includedTaskfile.Vars.Mapping[k] = o
+			}
+			for k, v := range includedTaskfile.Env.Mapping {
+				o := v
+				o.Dir = filepath.Join(dir, includedTask.Dir)
+				includedTaskfile.Env.Mapping[k] = o
+			}
+
+			for _, task := range includedTaskfile.Tasks {
+				if !filepath.IsAbs(task.Dir) {
+					task.Dir = filepath.Join(includedTask.Dir, task.Dir)
+				}
+			}
+		}
+
+		if err = taskfile.Merge(t, includedTaskfile, namespace); err != nil {
+			return err
+		}
+		return nil
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	if v < 3.0 {
+		path = filepath.Join(dir, fmt.Sprintf("Taskfile_%s.yml", runtime.GOOS))
+		if _, err = os.Stat(path); err == nil {
+			osTaskfile, err := readTaskfile(path)
+			if err != nil {
+				return nil, err
+			}
+			if err = taskfile.Merge(t, osTaskfile); err != nil {
+				return nil, err
+			}
+		}
+	}
+
+	for name, task := range t.Tasks {
+		if task == nil {
+			task = &taskfile.Task{}
+			t.Tasks[name] = task
+		}
+		task.Task = name
+	}
+
+	return t, nil
+}
+
+func readTaskfile(file string) (*taskfile.Taskfile, error) {
+	f, err := os.Open(file)
+	if err != nil {
+		return nil, err
+	}
+	var t taskfile.Taskfile
+	return &t, yaml.NewDecoder(f).Decode(&t)
+}

taskfile/read/taskvars.go

@@ -0,0 +1,45 @@
+package read
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"runtime"
+
+	"gopkg.in/yaml.v3"
+
+	"github.com/go-task/task/v3/taskfile"
+)
+
+// Taskvars reads a Taskvars for a given directory
+func Taskvars(dir string) (*taskfile.Vars, error) {
+	vars := &taskfile.Vars{}
+
+	path := filepath.Join(dir, "Taskvars.yml")
+	if _, err := os.Stat(path); err == nil {
+		vars, err = readTaskvars(path)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	path = filepath.Join(dir, fmt.Sprintf("Taskvars_%s.yml", runtime.GOOS))
+	if _, err := os.Stat(path); err == nil {
+		osVars, err := readTaskvars(path)
+		if err != nil {
+			return nil, err
+		}
+		vars.Merge(osVars)
+	}
+
+	return vars, nil
+}
+
+func readTaskvars(file string) (*taskfile.Vars, error) {
+	f, err := os.Open(file)
+	if err != nil {
+		return nil, err
+	}
+	var vars taskfile.Vars
+	return &vars, yaml.NewDecoder(f).Decode(&vars)
+}

taskfile/slice.go

@@ -0,0 +1,10 @@
+package taskfile
+
+func stringSliceContains(s []string, str string) bool {
+	for _, v := range s {
+		if v == str {
+			return true
+		}
+	}
+	return false
+}

taskfile/task.go

@@ -0,0 +1,96 @@
+package taskfile
+
+import (
+	"errors"
+)
+
+// Tasks represents a group of tasks
+type Tasks map[string]*Task
+
+// Task represents a task
+type Task struct {
+	Task          string
+	Cmds          []*Cmd
+	Deps          []*Dep
+	Label         string
+	Desc          string
+	Summary       string
+	Sources       []string
+	Generates     []string
+	Status        []string
+	Preconditions []*Precondition
+	Dir           string
+	Vars          *Vars
+	Env           *Vars
+	Silent        bool
+	Method        string
+	Prefix        string
+	IgnoreError   bool
+}
+
+var (
+	// ErrCantUnmarshalTask is returned for invalid task YAML
+	ErrCantUnmarshalTask = errors.New("task: can't unmarshal task value")
+)
+
+func (t *Task) Name() string {
+	if t.Label != "" {
+		return t.Label
+	}
+	return t.Task
+}
+
+func (t *Task) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var cmd Cmd
+	if err := unmarshal(&cmd); err == nil && cmd.Cmd != "" {
+		t.Cmds = append(t.Cmds, &cmd)
+		return nil
+	}
+
+	var cmds []*Cmd
+	if err := unmarshal(&cmds); err == nil && len(cmds) > 0 {
+		t.Cmds = cmds
+		return nil
+	}
+
+	var task struct {
+		Cmds          []*Cmd
+		Deps          []*Dep
+		Label         string
+		Desc          string
+		Summary       string
+		Sources       []string
+		Generates     []string
+		Status        []string
+		Preconditions []*Precondition
+		Dir           string
+		Vars          *Vars
+		Env           *Vars
+		Silent        bool
+		Method        string
+		Prefix        string
+		IgnoreError   bool `yaml:"ignore_error"`
+	}
+	if err := unmarshal(&task); err == nil {
+		t.Cmds = task.Cmds
+		t.Deps = task.Deps
+		t.Label = task.Label
+		t.Desc = task.Desc
+		t.Summary = task.Summary
+		t.Sources = task.Sources
+		t.Generates = task.Generates
+		t.Status = task.Status
+		t.Preconditions = task.Preconditions
+		t.Dir = task.Dir
+		t.Vars = task.Vars
+		t.Env = task.Env
+		t.Silent = task.Silent
+		t.Method = task.Method
+		t.Prefix = task.Prefix
+		t.IgnoreError = task.IgnoreError
+
+		return nil
+	}
+
+	return ErrCantUnmarshalTask
+}

taskfile/taskfile.go

@@ -0,0 +1,68 @@
+package taskfile
+
+import (
+	"fmt"
+	"strconv"
+)
+
+// Taskfile represents a Taskfile.yml
+type Taskfile struct {
+	Version    string
+	Expansions int
+	Output     string
+	Method     string
+	Includes   *IncludedTaskfiles
+	Vars       *Vars
+	Env        *Vars
+	Tasks      Tasks
+	Silent     bool
+	Dotenv     []string
+}
+
+// UnmarshalYAML implements yaml.Unmarshaler interface
+func (tf *Taskfile) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var taskfile struct {
+		Version    string
+		Expansions int
+		Output     string
+		Method     string
+		Includes   *IncludedTaskfiles
+		Vars       *Vars
+		Env        *Vars
+		Tasks      Tasks
+		Silent     bool
+		Dotenv     []string
+	}
+	if err := unmarshal(&taskfile); err != nil {
+		return err
+	}
+	tf.Version = taskfile.Version
+	tf.Expansions = taskfile.Expansions
+	tf.Output = taskfile.Output
+	tf.Method = taskfile.Method
+	tf.Includes = taskfile.Includes
+	tf.Vars = taskfile.Vars
+	tf.Env = taskfile.Env
+	tf.Tasks = taskfile.Tasks
+	tf.Silent = taskfile.Silent
+	tf.Dotenv = taskfile.Dotenv
+	if tf.Expansions <= 0 {
+		tf.Expansions = 2
+	}
+	if tf.Vars == nil {
+		tf.Vars = &Vars{}
+	}
+	if tf.Env == nil {
+		tf.Env = &Vars{}
+	}
+	return nil
+}
+
+// ParsedVersion returns the version as a float64
+func (tf *Taskfile) ParsedVersion() (float64, error) {
+	v, err := strconv.ParseFloat(tf.Version, 64)
+	if err != nil {
+		return 0, fmt.Errorf(`task: Could not parse taskfile version "%s": %v`, tf.Version, err)
+	}
+	return v, nil
+}

taskfile/taskfile_test.go

@@ -0,0 +1,66 @@
+package taskfile_test
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"gopkg.in/yaml.v3"
+
+	"github.com/go-task/task/v3/taskfile"
+)
+
+func TestCmdParse(t *testing.T) {
+	const (
+		yamlCmd      = `echo "a string command"`
+		yamlDep      = `"task-name"`
+		yamlTaskCall = `
+task: another-task
+vars:
+  PARAM1: VALUE1
+  PARAM2: VALUE2
+`
+	)
+	tests := []struct {
+		content  string
+		v        interface{}
+		expected interface{}
+	}{
+		{
+			yamlCmd,
+			&taskfile.Cmd{},
+			&taskfile.Cmd{Cmd: `echo "a string command"`},
+		},
+		{
+			yamlTaskCall,
+			&taskfile.Cmd{},
+			&taskfile.Cmd{Task: "another-task", Vars: &taskfile.Vars{
+				Keys: []string{"PARAM1", "PARAM2"},
+				Mapping: map[string]taskfile.Var{
+					"PARAM1": taskfile.Var{Static: "VALUE1"},
+					"PARAM2": taskfile.Var{Static: "VALUE2"},
+				},
+			}},
+		},
+		{
+			yamlDep,
+			&taskfile.Dep{},
+			&taskfile.Dep{Task: "task-name"},
+		},
+		{
+			yamlTaskCall,
+			&taskfile.Dep{},
+			&taskfile.Dep{Task: "another-task", Vars: &taskfile.Vars{
+				Keys: []string{"PARAM1", "PARAM2"},
+				Mapping: map[string]taskfile.Var{
+					"PARAM1": taskfile.Var{Static: "VALUE1"},
+					"PARAM2": taskfile.Var{Static: "VALUE2"},
+				},
+			}},
+		},
+	}
+	for _, test := range tests {
+		err := yaml.Unmarshal([]byte(test.content), test.v)
+		assert.NoError(t, err)
+		assert.Equal(t, test.expected, test.v)
+	}
+}

taskfile/var.go

@@ -0,0 +1,133 @@
+package taskfile
+
+import (
+	"errors"
+	"strings"
+
+	"gopkg.in/yaml.v3"
+)
+
+var (
+	// ErrCantUnmarshalVar is returned for invalid var YAML.
+	ErrCantUnmarshalVar = errors.New("task: can't unmarshal var value")
+)
+
+// Vars is a string[string] variables map.
+type Vars struct {
+	Keys    []string
+	Mapping map[string]Var
+}
+
+// UnmarshalYAML implements the yaml.Unmarshaler interface.
+func (vs *Vars) UnmarshalYAML(node *yaml.Node) error {
+	if node.Kind != yaml.MappingNode {
+		return errors.New("task: vars is not a map")
+	}
+
+	// NOTE(@andreynering): on this style of custom unmarsheling,
+	// even number contains the keys, while odd numbers contains
+	// the values.
+	for i := 0; i < len(node.Content); i += 2 {
+		keyNode := node.Content[i]
+		valueNode := node.Content[i+1]
+
+		var v Var
+		if err := valueNode.Decode(&v); err != nil {
+			return err
+		}
+		vs.Set(keyNode.Value, v)
+	}
+	return nil
+}
+
+// Merge merges the given Vars into the caller one
+func (vs *Vars) Merge(other *Vars) {
+	other.Range(func(key string, value Var) error {
+		vs.Set(key, value)
+		return nil
+	})
+}
+
+// Set sets a value to a given key
+func (vs *Vars) Set(key string, value Var) {
+	if vs.Mapping == nil {
+		vs.Mapping = make(map[string]Var, 1)
+	}
+	if !stringSliceContains(vs.Keys, key) {
+		vs.Keys = append(vs.Keys, key)
+	}
+	vs.Mapping[key] = value
+}
+
+// Range allows you to loop into the vars in its right order
+func (vs *Vars) Range(yield func(key string, value Var) error) error {
+	if vs == nil {
+		return nil
+	}
+	for _, k := range vs.Keys {
+		if err := yield(k, vs.Mapping[k]); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// ToCacheMap converts Vars to a map containing only the static
+// variables
+func (vs *Vars) ToCacheMap() (m map[string]interface{}) {
+	m = make(map[string]interface{}, vs.Len())
+	vs.Range(func(k string, v Var) error {
+		if v.Sh != "" {
+			// Dynamic variable is not yet resolved; trigger
+			// <no value> to be used in templates.
+			return nil
+		}
+
+		if v.Live != nil {
+			m[k] = v.Live
+		} else {
+			m[k] = v.Static
+		}
+		return nil
+	})
+	return
+}
+
+// Len returns the size of the map
+func (vs *Vars) Len() int {
+	if vs == nil {
+		return 0
+	}
+	return len(vs.Keys)
+}
+
+// Var represents either a static or dynamic variable.
+type Var struct {
+	Static string
+	Live   interface{}
+	Sh     string
+	Dir    string
+}
+
+// UnmarshalYAML implements yaml.Unmarshaler interface.
+func (v *Var) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var str string
+	if err := unmarshal(&str); err == nil {
+		if strings.HasPrefix(str, "$") {
+			v.Sh = strings.TrimPrefix(str, "$")
+		} else {
+			v.Static = str
+		}
+		return nil
+	}
+
+	var sh struct {
+		Sh string
+	}
+	if err := unmarshal(&sh); err == nil {
+		v.Sh = sh.Sh
+		return nil
+	}
+
+	return ErrCantUnmarshalVar
+}

testdata/checksum/.gitignore

@@ -0,0 +1,2 @@
+.task/
+generated.txt

testdata/checksum/Taskfile.yml

@@ -0,0 +1,12 @@
+version: '3'
+
+tasks:
+  build:
+    cmds:
+      - cp ./source.txt ./generated.txt
+    sources:
+      - ./**/glob-with-inexistent-file.txt
+      - ./source.txt
+    generates:
+      - ./generated.txt
+    method: checksum

testdata/checksum/source.txt

@@ -0,0 +1 @@
+Hello, World!

testdata/concurrency/Taskfile.yml

@@ -0,0 +1,32 @@
+version: '2'
+
+tasks:
+  default:
+    deps:
+      - t1
+
+  t1:
+    deps:
+      - t3
+      - t4
+    cmds:
+      - task: t2
+      - echo done 1
+  t2:
+    deps:
+      - t5
+      - t6
+    cmds:
+      - echo done 2
+  t3:
+    cmds:
+      - echo done 3
+  t4:
+    cmds:
+      - echo done 4
+  t5:
+    cmds:
+      - echo done 5
+  t6:
+    cmds:
+      - echo done 6

testdata/cyclic/Taskfile.yml

@@ -0,0 +1,10 @@
+version: '3'
+
+tasks:
+  task-1:
+    deps:
+      - task: task-2
+
+  task-2:
+    deps:
+      - task: task-1

testdata/deps/.gitignore

@@ -0,0 +1 @@
+*.txt

testdata/deps/Taskfile.yml

@@ -0,0 +1,56 @@
+version: '3'
+
+tasks:
+  default:
+    deps: [d1, d2, d3]
+
+  d1:
+    deps: [d11, d12, d13]
+    cmds:
+      - echo 'Text' > d1.txt
+
+  d2:
+    deps: [d21, d22, d23]
+    cmds:
+      - echo 'Text' > d2.txt
+
+  d3:
+    deps: [d31, d32, d33]
+    cmds:
+      - echo 'Text' > d3.txt
+
+  d11:
+    cmds:
+      - echo 'Text' > d11.txt
+
+  d12:
+    cmds:
+      - echo 'Text' > d12.txt
+
+  d13:
+    cmds:
+      - echo 'Text' > d13.txt
+
+  d21:
+    cmds:
+      - echo 'Text' > d21.txt
+
+  d22:
+    cmds:
+      - echo 'Text' > d22.txt
+
+  d23:
+    cmds:
+      - echo 'Text' > d23.txt
+
+  d31:
+    cmds:
+      - echo 'Text' > d31.txt
+
+  d32:
+    cmds:
+      - echo 'Text' > d32.txt
+
+  d33:
+    cmds:
+      - echo 'Text' > d33.txt

testdata/dir/Taskfile.yml

@@ -0,0 +1,7 @@
+version: '3'
+
+tasks:
+  whereami:
+    cmds:
+      - pwd
+    silent: true

testdata/dir/dynamic_var/.gitignore

@@ -0,0 +1 @@
+*.txt

testdata/dir/dynamic_var/Taskfile.yml

@@ -0,0 +1,33 @@
+version: '3'
+
+includes:
+  sub:
+    taskfile: subdirectory
+    dir: subdirectory
+
+vars:
+  DIRECTORY: subdirectory
+
+tasks:
+  default:
+    - task: from-root-taskfile
+    - task: sub:from-included-taskfile
+    - task: sub:from-included-taskfile-task
+    - task: from-interpolated-dir
+
+  from-root-taskfile:
+    cmds:
+      - echo '{{.TASK_DIR}}' > from_root_taskfile.txt
+    dir: subdirectory
+    vars:
+      TASK_DIR:
+        sh: basename $(pwd)
+    silent: true
+
+  from-interpolated-dir:
+    cmds:
+      - echo '{{.INTERPOLATED_DIR}}' > from_interpolated_dir.txt
+    dir: '{{.DIRECTORY}}'
+    vars:
+      INTERPOLATED_DIR:
+        sh: basename $(pwd)

testdata/dir/dynamic_var/subdirectory/Taskfile.yml

@@ -0,0 +1,19 @@
+version: '3'
+
+vars:
+  TASKFILE_DIR:
+    sh: basename $(pwd)
+
+tasks:
+  from-included-taskfile:
+    cmds:
+      - echo '{{.TASKFILE_DIR}}' > from_included_taskfile.txt
+    silent: true
+
+  from-included-taskfile-task:
+    cmds:
+      - echo '{{.TASKFILE_TASK_DIR}}' > from_included_taskfile_task.txt
+    silent: true
+    vars:
+      TASKFILE_TASK_DIR:
+        sh: basename $(pwd)

testdata/dir/explicit_doesnt_exist/Taskfile.yml

@@ -0,0 +1,8 @@
+version: '3'
+
+tasks:
+  whereami:
+    dir: createme
+    cmds:
+      - pwd
+    silent: true

testdata/dir/explicit_exists/Taskfile.yml

@@ -0,0 +1,8 @@
+version: '3'
+
+tasks:
+  whereami:
+    dir: exists
+    cmds:
+      - pwd
+    silent: true

testdata/dotenv/.gitignore

@@ -0,0 +1 @@
+*.txt

testdata/dotenv/default/Taskfile.yml

@@ -0,0 +1,8 @@
+version: '3'
+
+dotenv: ['../include1/.env', '../include1/envs/.env']
+
+tasks:
+  default:
+    cmds:
+      - echo "INCLUDE1='$INCLUDE1' INCLUDE2='$INCLUDE2'" > include.txt