Merge pull request #66713 from basvandijk/rustfmt-from-rust-src

rustfmt: use the src as defined by the git submodule in rust

pkgs/development/compilers/rust/default.nix

@@ -59,6 +59,7 @@
         pkgsBuildHost = pkgsBuildBuild // { targetPackages.stdenv = llvmPackages_5.stdenv; };
         pkgsBuildTarget = pkgsBuildTarget // { targetPackages.stdenv = llvmPackages_5.stdenv; };
       });
+      rustfmt = self.callPackage ./rustfmt.nix { inherit Security; };
       cargo = self.callPackage ./cargo.nix {
         # Use boot package set to break cycle
         rustPlatform = bootRustPlatform;

pkgs/development/compilers/rust/rustfmt.nix

@@ -0,0 +1,30 @@
+{ stdenv, rustPlatform, Security }:
+
+rustPlatform.buildRustPackage rec {
+  name = "rustfmt-${version}";
+  inherit (rustPlatform.rust.rustc) version src;
+
+  # the rust source tarball already has all the dependencies vendored, no need to fetch them again
+  cargoVendorDir = "vendor";
+  preBuild = "pushd src/tools/rustfmt";
+  preInstall = "popd";
+
+  buildInputs = stdenv.lib.optional stdenv.isDarwin Security;
+
+  # As of 1.0.0 and rustc 1.30 rustfmt requires a nightly compiler
+  RUSTC_BOOTSTRAP = 1;
+
+  # we run tests in debug mode so tests look for a debug build of
+  # rustfmt. Anyway this adds nearly no compilation time.
+  preCheck = ''
+    cargo build
+  '';
+
+  meta = with stdenv.lib; {
+    description = "A tool for formatting Rust code according to style guidelines";
+    homepage = https://github.com/rust-lang-nursery/rustfmt;
+    license = with licenses; [ mit asl20 ];
+    maintainers = with maintainers; [ globin basvandijk ];
+    platforms = platforms.all;
+  };
+}