fix: make task failure errors include stack of running tasks (#2286)

Previously if a task was run as a dependency of another task,
the error message simply reported something like:

    exit status 1

It is desirable instead to name the root task and all child tasks in the tree
to the failing task.

After this PR, the error message will read:

    task: Failed to run task "root": task: Failed to run task "failing-task": exit status 1

errors/errors_task.go

@@ -54,6 +54,10 @@ func (err *TaskRunError) TaskExitCode() int {
 	return err.Code()
 }
 
+func (err *TaskRunError) Unwrap() error {
+	return err.Err
+}
+
 // TaskInternalError when the user attempts to invoke a task that is internal.
 type TaskInternalError struct {
 	TaskName string

executor_test.go

@@ -665,6 +665,15 @@ func TestLabel(t *testing.T) {
 		),
 		WithTask("foo"),
 	)
+
+	NewExecutorTest(t,
+		WithName("label in error"),
+		WithExecutorOptions(
+			task.WithDir("testdata/label_error"),
+		),
+		WithTask("foo"),
+		WithRunError(),
+	)
 }
 
 func TestPromptInSummary(t *testing.T) {

task.go

@@ -150,7 +150,7 @@ func (e *Executor) RunTask(ctx context.Context, call *Call) error {
 	release := e.acquireConcurrencyLimit()
 	defer release()
 
-	return e.startExecution(ctx, t, func(ctx context.Context) error {
+	if err = e.startExecution(ctx, t, func(ctx context.Context) error {
 		e.Logger.VerboseErrf(logger.Magenta, "task: %q started\n", call.Task)
 		if err := e.runDeps(ctx, t); err != nil {
 			return err
@@ -228,16 +228,16 @@ func (e *Executor) RunTask(ctx context.Context, call *Call) error {
 					deferredExitCode = uint8(exitCode)
 				}
 
-				if call.Indirect {
-					return err
-				}
-
-				return &errors.TaskRunError{TaskName: t.Task, Err: err}
+				return err
 			}
 		}
 		e.Logger.VerboseErrf(logger.Magenta, "task: %q finished\n", call.Task)
 		return nil
-	})
+	}); err != nil {
+		return &errors.TaskRunError{TaskName: t.Name(), Err: err}
+	}
+
+	return nil
 }
 
 func (e *Executor) mkdir(t *ast.Task) error {

task_test.go

@@ -569,7 +569,9 @@ func TestCyclicDep(t *testing.T) {
 		task.WithStderr(io.Discard),
 	)
 	require.NoError(t, e.Setup())
-	assert.IsType(t, &errors.TaskCalledTooManyTimesError{}, e.Run(t.Context(), &task.Call{Task: "task-1"}))
+	err := e.Run(t.Context(), &task.Call{Task: "task-1"})
+	var taskCalledTooManyTimesError *errors.TaskCalledTooManyTimesError
+	assert.ErrorAs(t, err, &taskCalledTooManyTimesError)
 }
 
 func TestTaskVersion(t *testing.T) {

testdata/label_error/Taskfile.yml

@@ -0,0 +1,7 @@
+version: '3'
+
+tasks:
+  foo:
+    label: "foobar"
+    cmds:
+      - "false"

testdata/label_error/testdata/TestLabel-label_in_error-err-run.golden

@@ -0,0 +1 @@
+task: Failed to run task "foobar": exit status 1

testdata/label_error/testdata/TestLabel-label_in_error.golden

@@ -0,0 +1 @@
+task: [foobar] false

testdata/precondition/testdata/TestPrecondition-a_precondition_was_not_met-err-run.golden

@@ -1 +1 @@
-task: precondition not met
+task: Failed to run task "impossible": task: precondition not met

testdata/precondition/testdata/TestPrecondition-precondition_in_cmd_fails_the_task-err-run.golden

@@ -1 +1 @@
-task: Failed to run task "executes_failing_task_as_cmd": task: precondition not met
+task: Failed to run task "executes_failing_task_as_cmd": task: Failed to run task "impossible": task: precondition not met

testdata/precondition/testdata/TestPrecondition-precondition_in_dependency_fails_the_task-err-run.golden

@@ -1 +1 @@
-task: precondition not met
+task: Failed to run task "depends_on_impossible": task: Failed to run task "impossible": task: precondition not met

testdata/prompt/testdata/TestPromptAssumeYes-task_should_raise_errors.TaskCancelledError-err-run.golden

@@ -1 +1 @@
-task: Task "foo" cancelled by user
+task: Failed to run task "foo": task: Task "foo" cancelled by user

testdata/prompt/testdata/TestPromptInSummary-test_Enter_stops_task-test_Enter_stops_task-err-run.golden

@@ -1 +1 @@
-task: Task "foo" cancelled by user
+task: Failed to run task "foo": task: Task "foo" cancelled by user

testdata/prompt/testdata/TestPromptInSummary-test_junk_value_stops_task-test_junk_value_stops_task-err-run.golden

@@ -1 +1 @@
-task: Task "foo" cancelled by user
+task: Failed to run task "foo": task: Task "foo" cancelled by user

testdata/prompt/testdata/TestPromptInSummary-test_stops_task-test_stops_task-err-run.golden

@@ -1 +1 @@
-task: Task "foo" cancelled by user
+task: Failed to run task "foo": task: Task "foo" cancelled by user