From c3a5233afe5bda82902673480436360d9caad526 Mon Sep 17 00:00:00 2001
From: Marcin Kulik <m@ku1ik.com>
Date: Sat, 20 Apr 2024 14:02:53 +0200
Subject: [PATCH] Add package to flake outputs

---
 flake.lock | 71 +++++++++++++++++++++++++++++++++++++++++++++++++++++-
 flake.nix  | 61 ++++++++++++++++++++++++++++++++++------------
 2 files changed, 116 insertions(+), 16 deletions(-)

diff --git a/flake.lock b/flake.lock
index b360569..533caa8 100644
--- a/flake.lock
+++ b/flake.lock
@@ -18,6 +18,24 @@
         "type": "github"
       }
     },
+    "flake-utils_2": {
+      "inputs": {
+        "systems": "systems_2"
+      },
+      "locked": {
+        "lastModified": 1705309234,
+        "narHash": "sha256-uNRRNRKmJyCRC/8y1RqBkqWBLM034y4qN7EprSdmgyA=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "1ef2e671c3b0c19053962c07dbda38332dcebf26",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1707877513,
@@ -34,10 +52,46 @@
         "type": "github"
       }
     },
+    "nixpkgs_2": {
+      "locked": {
+        "lastModified": 1706487304,
+        "narHash": "sha256-LE8lVX28MV2jWJsidW13D2qrHU/RUUONendL2Q/WlJg=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "90f456026d284c22b3e3497be980b2e47d0b28ac",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixpkgs-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
     "root": {
       "inputs": {
         "flake-utils": "flake-utils",
-        "nixpkgs": "nixpkgs"
+        "nixpkgs": "nixpkgs",
+        "rust-overlay": "rust-overlay"
+      }
+    },
+    "rust-overlay": {
+      "inputs": {
+        "flake-utils": "flake-utils_2",
+        "nixpkgs": "nixpkgs_2"
+      },
+      "locked": {
+        "lastModified": 1713579131,
+        "narHash": "sha256-j/lrqFNzm7SdlBlKX43kA2Wp0OaGVOUjQGnER9//4Ao=",
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "rev": "67e961704b80454f1ba6595b02e26afc9af4cdce",
+        "type": "github"
+      },
+      "original": {
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "type": "github"
       }
     },
     "systems": {
@@ -54,6 +108,21 @@
         "repo": "default",
         "type": "github"
       }
+    },
+    "systems_2": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
     }
   },
   "root": "root",
diff --git a/flake.nix b/flake.nix
index 84094fe..e6d7dbc 100644
--- a/flake.nix
+++ b/flake.nix
@@ -3,22 +3,53 @@
 
   inputs = {
     nixpkgs.url = github:nixos/nixpkgs/nixpkgs-unstable;
+    rust-overlay.url = github:oxalica/rust-overlay;
     flake-utils.url = github:numtide/flake-utils;
   };
 
-  outputs = { self, nixpkgs, flake-utils }:
-    flake-utils.lib.eachDefaultSystem
-      (system:
-        let pkgs = nixpkgs.legacyPackages.${system}; in
-        {
-          devShells.default = pkgs.mkShell {
-            nativeBuildInputs = with pkgs; [
-              rustup
-            ] ++ (lib.optionals stdenv.isDarwin [
-              libiconv
-              darwin.apple_sdk.frameworks.Foundation
-            ]);
-          };
-        }
-      );
+  outputs = { self, nixpkgs, rust-overlay, flake-utils }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        overlays = [ (import rust-overlay) ];
+        pkgs = import nixpkgs { inherit system overlays; };
+        cargoToml = builtins.fromTOML (builtins.readFile ./Cargo.toml);
+        msrv = cargoToml.package.rust-version;
+
+        buildDeps = rust: with pkgs; [
+          rust
+        ] ++ (lib.optionals stdenv.isDarwin [
+          libiconv
+          darwin.apple_sdk.frameworks.Foundation
+        ]) ++ testDeps;
+
+        testDeps = with pkgs; [
+          python3
+          procps  # provides `w` binary
+        ];
+
+        mkDevShell = rust: pkgs.mkShell {
+          nativeBuildInputs = buildDeps (rust.override {
+            extensions = [ "rust-src" ];
+          });
+
+          RUST_BACKTRACE = 1;
+        };
+
+        mkPackage = rust: (pkgs.makeRustPlatform {
+          cargo = rust;
+          rustc = rust;
+        }).buildRustPackage {
+          inherit (cargoToml.package) name version;
+          src = ./.;
+          cargoLock.lockFile = ./Cargo.lock;
+          nativeBuildInputs = buildDeps rust;
+          dontUseCargoParallelTests = true;
+        };
+      in
+      {
+        devShells.default = mkDevShell pkgs.rust-bin.stable.latest.default;
+        devShells.msrv = mkDevShell pkgs.rust-bin.stable.${msrv}.default;
+        packages.default = mkPackage pkgs.rust-bin.stable.latest.minimal;
+      }
+    );
 }