Git workspaces

crate2nix/Cargo.nix

@@ -3809,4 +3809,3 @@ rec {
   #
   };
 }
-

crate2nix/Cargo.toml

@@ -15,6 +15,7 @@ resolver = "2"
 [dependencies]
 anyhow = "1.0.28"
 cargo_metadata = "0.18"
+cargo = "0.72"
 cargo-platform = "0.1"
 hex = "0.4"
 itertools = "0.12"

crate2nix/default.nix

@@ -45,6 +45,11 @@ let
       cssparser-macros = attrs: assert builtins.trace "cssparser" true;{
         buildInputs = lib.optionals stdenv.isDarwin [ darwin.apple_sdk.frameworks.Security ];
       };
+      libgit2-sys = old: {
+        nativeBuildInputs = (old.nativeBuildInputs or []) ++ pkgs.libgit2.nativeBuildInputs;
+        buildInputs = (old.buildInputs or []) ++ pkgs.libgit2.buildInputs ++ [pkgs.iconv.dev pkgs.apple-sdk.frameworks.CoreFoundation];
+        propagatedBuildInputs = (old.propagatedBuildInputs or [ ]) ++ pkgs.libgit2.propagatedBuildInputs;
+      };
     };
   };
   set_templates = if release then "" else "--set TEMPLATES_DIR ${./templates}";

crate2nix/flake-module.nix

@@ -42,6 +42,6 @@
         };
       };
 
-      config.packages.default = pkgs.callPackage ./default.nix { };
+      # config.packages.default = pkgs.callPackage ./default.nix { };
     };
 }

crate2nix/src/main.rs

@@ -150,6 +150,20 @@ pub enum Opt {
         )]
         output: PathBuf,
     },
+
+    #[structopt(
+        name = "resolve-manifest",
+        about = "Resolve fields inherited from a workspace, so that the manifest can be processed stand-alone."
+    )]
+    ResolveManifest {
+        #[structopt(
+            short = "f",
+            long = "cargo-toml",
+            parse(from_os_str),
+            help = "The path to the Cargo.toml of the project."
+        )]
+        cargo_toml: PathBuf,
+    },
 }
 
 #[derive(Debug, StructOpt, Deserialize, Serialize)]
@@ -463,7 +477,24 @@ fn main() -> anyhow::Result<()> {
         } => {
             command.execute(&crate2nix_json)?;
         }
+        Opt::ResolveManifest { cargo_toml } => {
+            let manifest = resolve_manifest(&cargo_toml)?;
+            let toml = toml::to_string_pretty(manifest.original())?;
+            println!("{toml}");
+        }
     }
 
     Ok(())
 }
+
+fn resolve_manifest(cargo_toml: &Path) -> cargo::CargoResult<cargo::core::Manifest> {
+    use cargo::core::SourceId;
+
+    let full_path = cargo_toml.canonicalize()?;
+    let source_id = SourceId::for_path(&full_path)?;
+
+    let config = cargo::Config::default()?;
+    let (pkg, _paths) = cargo::ops::read_package(&full_path, source_id, &config)?;
+
+    Ok(pkg.manifest().clone())
+}

docs/flake-module.nix

@@ -1,6 +1,6 @@
 {
   perSystem = { config, self', inputs', pkgs, lib, system, ... }:
-    let nodejs = pkgs.nodejs_21; in {
+    let nodejs = pkgs.nodejs_20; in {
       devshells.default = {
         commands = [
           { package = nodejs; category = "docs"; }

docs/src/content/docs/00_guides/42_custom_toolchains.md

@@ -0,0 +1,64 @@
+---
+title: Custom Toolchains
+---
+
+One way to use a custom rust toolchain with `crate2nix` is to
+import nixpkgs with an overlay for `rustc`.
+
+Here is an example flake using [fenix]:
+
+```nix
+
+{
+  description = "containix";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/24.05";
+    fenix = {
+      url = "github:nix-community/fenix";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
+    flake-utils.url = "github:numtide/flake-utils";
+    crate2nix.url = "github:nix-community/crate2nix";
+  };
+
+  outputs =
+    {
+      self,
+      nixpkgs,
+      flake-utils,
+      fenix,
+      crate2nix,
+    }:
+    flake-utils.lib.eachDefaultSystem (
+      system:
+      let
+        toolchain = fenix.packages.${system}.stable.defaultToolchain;
+
+        pkgs = import nixpkgs {
+          inherit system;
+          overlays = [
+            (final: prev: {
+              rustc = toolchain;
+              cargo = toolchain;
+            })
+          ];
+        };
+
+        crate2nix' = pkgs.callPackage (import "${crate2nix}/tools.nix") {};
+        cargoNix = crate2nix.appliedCargoNix {
+          name = "my-crate";
+          src = ./.;
+        };
+      in
+      {
+        packages = {
+          default = cargoNix.rootCrate.build;
+        };
+      }
+    );
+}
+
+```
+
+[fenix]: https://github.com/nix-community/fenix

docs/src/content/docs/00_guides/80_using_a_rust_overlay.md

@@ -0,0 +1,78 @@
+---
+title: Using a Rust overlay
+---
+
+It's possible to use a Rust overlay such as `rust-overlay` with `crate2nix`.
+This can be used for pinning the Rust toolchain version, or to use a newer toolchain version than is available in Nixpkgs.
+
+In a flake with flake-parts:
+
+```nix
+# flake.nix
+{
+  # ...
+
+  inputs = {
+    flake-parts = {
+      url = "github:hercules-ci/flake-parts";
+      inputs.nixpkgs-lib.follows = "nixpkgs";
+    };
+    crate2nix.url = "github:nix-community/crate2nix";
+    # ...
+  };
+
+  outputs =
+    inputs @ { self
+    , nixpkgs
+    , flake-parts
+    , rust-overlay
+    , crate2nix
+    , ...
+    }:
+    flake-parts.lib.mkFlake { inherit inputs; } {
+      systems = [
+        "x86_64-linux"
+        "aarch64-linux"
+        "x86_64-linux"
+        "aarch64-darwin"
+      ];
+
+      perSystem = { system, lib, inputs', ... }:
+        let
+          pkgs = import nixpkgs {
+            inherit system;
+
+            overlays = [ rust-overlay.overlays.default ];
+          };
+
+          buildRustCrateForPkgs =
+            crate:
+            pkgs.buildRustCrate.override {
+              rustc = pkgs.rust-bin.stable.latest.default;
+              cargo = pkgs.rust-bin.stable.latest.default;
+            };
+
+          generatedCargoNix = inputs.crate2nix.tools.${system}.appliedCargoNix {
+            name = "rustnix";
+            src = ./.;
+          };
+
+          cargoNix = import generatedCargoNix {
+            inherit pkgs buildRustCrateForPkgs;
+          };
+        in
+          rec {
+            checks = {
+              rustnix = cargoNix.rootCrate.build.override {
+                runTests = true;
+              };
+            };
+
+            packages = {
+              rustnix = cargoNix.rootCrate.build;
+              default = packages.rustnix;
+            };
+          };
+    };
+}
+```

docs/src/content/docs/90_reference/90_CHANGELOG.md

@@ -5,7 +5,7 @@ description: A list of all major changes per version.
 
 ## 0.14.x - 0.15.0 (unreleased)
 
-TODO
+* [#359](https://github.com/nix-community/crate2nix/issues/359): Document using `rust-overlay`.
 
 ## 0.14.x - 0.14.1 (2024-06-30)
 

docs/src/content/docs/index.mdx

@@ -20,7 +20,7 @@ You can
 dependency tree from cargo. Therefore, it will use the exact same library versions as cargo and respect any locked down
 version in `Cargo.lock`.
 
-**Smart caching**: It caches the builds of individual creates so that nix rebuilds exactly the crates that need to be rebuilt.
+**Smart caching**: It caches the builds of individual crates so that nix rebuilds exactly the crates that need to be rebuilt.
 Compare that to docker layers...
 
 **Nix ecosystem goodness**: You can use all things that make the nix/NixOS ecosystem great, e.g. distributed/remote builds,

flake.nix

@@ -1,6 +1,6 @@
 {
   description = ''
-    crate2nix generates [nix](https://nixos.org/nix/) build files for [rust](https://www.rust-lang.org/) 
+    crate2nix generates [nix](https://nixos.org/nix/) build files for [rust](https://www.rust-lang.org/)
     crates using [cargo](https://crates.io/).
   '';
 

nix/devshell/flake-module.nix

@@ -22,6 +22,10 @@
           gnugrep
           utillinux
           cacert
+          iconv.dev
+          darwin.apple_sdk.frameworks.CoreFoundation
+          darwin.apple_sdk.frameworks.Security
+          curl.out
         ];
 
         commands = with pkgs; [
@@ -30,12 +34,12 @@
           { package = nixpkgs-fmt; category = "nix"; }
           { package = nix; category = "nix"; }
           { package = nix-prefetch-git; category = "nix"; }
-          {
-            name = "nix-test";
-            package = (import ../nix-test-runner.nix { inherit pkgs; });
-            category = "nix";
-            help = "nix test runner for unit tests.";
-          }
+          # {
+          #   name = "nix-test";
+          #   package = (import ../nix-test-runner.nix { inherit pkgs; });
+          #   category = "nix";
+          #   help = "nix test runner for unit tests.";
+          # }
           { package = inputs'.cachix.packages.default; category = "nix"; }
         ];
 

nix/nix-test-runner.nix

@@ -5,7 +5,7 @@ in
 { pkgs ? import ./nixpkgs.nix { }
   # Use last pinned crate2nix packages to build the test runner
   # so that it works even if we have broken stuff!
-, tools ? pkgs.callPackage "${builtins.fetchTree flakeLock.nodes.crate2nix_stable.locked}/tools.nix" { }
+, tools ? pkgs.callPackage ../tools.nix { }
 }:
 let
   nixTestRunner = tools.appliedCargoNix {

tools.nix

@@ -11,12 +11,20 @@
 , strictDeprecation ? true
 }:
 let
-  cargoNix = pkgs.callPackage ./crate2nix/Cargo.nix { inherit strictDeprecation; };
+  defaultCrateOverrides = pkgs.defaultCrateOverrides // {
+    libgit2-sys = old: {
+      nativeBuildInputs = (old.nativeBuildInputs or []) ++ pkgs.libgit2.nativeBuildInputs;
+      buildInputs = (old.buildInputs or []) ++ pkgs.libgit2.buildInputs ++ [pkgs.iconv.dev pkgs.apple_sdk.frameworks.CoreFoundation];
+      propagatedBuildInputs = (old.propagatedBuildInputs or [ ]) ++ pkgs.libgit2.propagatedBuildInputs;
+    };
+  };
+
+  cargoNix = pkgs.callPackage ./crate2nix/Cargo.nix { inherit strictDeprecation defaultCrateOverrides; workspaceSrc = ./.; };
   crate2nix = cargoNix.rootCrate.build;
 in
 rec {
 
-  /* Returns a derivation containing the whole top-level function generated 
+  /* Returns a derivation containing the whole top-level function generated
     by crate2nix (`Cargo.nix`) which is typically called with `pkgs.callPackage`.
 
     name: will be part of the derivation name
@@ -44,7 +52,7 @@ rec {
     stdenv.mkDerivation {
       name = "${name}-crate2nix";
 
-      buildInputs = [ pkgs.cargo pkgs.jq crate2nix ];
+      buildInputs = [ pkgs.cargo pkgs.jq crate2nix pkgs.nix ];
       preferLocalBuild = true;
 
       inherit src;
@@ -429,9 +437,13 @@ rec {
               ''
                 mkdir -p $out
                 cp -apR ${src}/${pathToExtract}/* $out
+                cd $out
+
+                mv ./Cargo.toml ./Cargo.toml.orig
+                ${crate2nix}/bin/crate2nix resolve-manifest --cargo-toml ${src}/${pathToExtract}/Cargo.toml > ./Cargo.toml
+
                 echo '{"package":null,"files":{}}' > $out/.cargo-checksum.json
               '';
-
         };
       };
   };