Auto-update README when supported branches list changes

.github/workflows/build.yaml

@@ -38,6 +38,9 @@ jobs:
         uses: DeterminateSystems/flakehub-cache-action@main
 
       - name: Build and cache dev shell for ${{ matrix.systems.nix-system }} on ${{ matrix.systems.runner }}
+        # We still support this system but caching the dev shell fails due to system support mismatch,
+        # and we don't really need this cached anyway
+        if: ${{ matrix.systems.nix-system != 'x86_64-darwin' }}
         run: |
           nix build -L ".#devShells.${{ matrix.systems.nix-system }}.default"
 

.github/workflows/ref-statuses.yaml

@@ -24,11 +24,16 @@ jobs:
           ref_statuses_json=$(nix develop --command cargo run --features ref-statuses -- --get-ref-statuses | jq --sort-keys .)
           echo "${ref_statuses_json}" > ref-statuses.json
 
+      - name: Update README in light of new list
+        if: failure()
+        run: |
+          nix develop --command update-readme
+
       - name: Create pull request
         if: failure()
         uses: peter-evans/create-pull-request@v6
         with:
-          commit-message: Update ref-statuses.json to new valid Git refs list
+          commit-message: Update ref-statuses.json to new valid Git refs list and update README
           title: Update ref-statuses.json
           body: |
             Nixpkgs has changed its list of maintained references. This PR updates `ref-statuses.json` to reflect that change.

README.md

@@ -162,3 +162,4 @@ If you'd like to help make the parser more exhaustive, [pull requests][prs] are
 [rust]: https://rust-lang.org
 [telemetry]: https://github.com/DeterminateSystems/nix-flake-checker/blob/main/src/telemetry.rs#L29-L43
 [val]: https://docs.rs/serde_json/latest/serde_json/value/enum.Value.html
+

flake.nix

@@ -11,42 +11,64 @@
       url = "https://flakehub.com/f/nix-community/naersk/0";
       inputs.nixpkgs.follows = "nixpkgs";
     };
+
+    easy-template = {
+      url = "https://flakehub.com/f/DeterminateSystems/easy-template/0";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
   };
 
-  outputs = { self, ... }@inputs:
+  outputs =
+    { self, ... }@inputs:
     let
       lastModifiedDate = self.lastModifiedDate or self.lastModified or "19700101";
       version = "${builtins.substring 0 8 lastModifiedDate}-${self.shortRev or "dirty"}";
 
-      supportedSystems = [ "x86_64-linux" "aarch64-linux" "x86_64-darwin" "aarch64-darwin" ];
-
-      forSystems = s: f: inputs.nixpkgs.lib.genAttrs s (system: f rec {
-        inherit system;
-        pkgs = import inputs.nixpkgs {
-          inherit system;
-          overlays = [ self.overlays.default ];
-        };
-      });
+      supportedSystems = [
+        "x86_64-linux"
+        "aarch64-linux"
+        "x86_64-darwin"
+        "aarch64-darwin"
+      ];
+
+      forSystems =
+        s: f:
+        inputs.nixpkgs.lib.genAttrs s (
+          system:
+          f rec {
+            inherit system;
+            pkgs = import inputs.nixpkgs {
+              inherit system;
+              overlays = [ self.overlays.default ];
+            };
+          }
+        );
 
       forAllSystems = forSystems supportedSystems;
     in
     {
-      overlays.default = final: prev:
+      overlays.default =
+        final: prev:
         let
           inherit (final.stdenv.hostPlatform) system;
 
-          rustToolchain = with inputs.fenix.packages.${system};
-            combine ([
-              stable.clippy
-              stable.rustc
-              stable.cargo
-              stable.rustfmt
-              stable.rust-src
-            ] ++ inputs.nixpkgs.lib.optionals (system == "x86_64-linux") [
-              targets.x86_64-unknown-linux-musl.stable.rust-std
-            ] ++ inputs.nixpkgs.lib.optionals (system == "aarch64-linux") [
-              targets.aarch64-unknown-linux-musl.stable.rust-std
-            ]);
+          rustToolchain =
+            with inputs.fenix.packages.${system};
+            combine (
+              [
+                stable.clippy
+                stable.rustc
+                stable.cargo
+                stable.rustfmt
+                stable.rust-src
+              ]
+              ++ inputs.nixpkgs.lib.optionals (system == "x86_64-linux") [
+                targets.x86_64-unknown-linux-musl.stable.rust-std
+              ]
+              ++ inputs.nixpkgs.lib.optionals (system == "aarch64-linux") [
+                targets.aarch64-unknown-linux-musl.stable.rust-std
+              ]
+            );
         in
         {
           inherit rustToolchain;
@@ -57,76 +79,104 @@
           };
         };
 
-      packages = forAllSystems ({ pkgs, system }: rec {
-        default = flake-checker;
-
-        flake-checker = pkgs.naerskLib.buildPackage
-          ({
-            name = "flake-checker";
-            src = self;
-            doCheck = true;
-            nativeBuildInputs = with pkgs; [ ] ++ lib.optionals stdenv.isDarwin [ libiconv ];
-          } // pkgs.lib.optionalAttrs pkgs.stdenv.isLinux {
-            CARGO_BUILD_TARGET =
-              if system == "x86_64-linux" then
-                "x86_64-unknown-linux-musl"
-              else if system == "aarch64-linux" then
-                "aarch64-unknown-linux-musl"
-              else
-                throw "Unsupported Linux system: ${system}";
-            CARGO_BUILD_RUSTFLAGS = "-C target-feature=+crt-static";
-          });
-      });
-
-      devShells = forAllSystems ({ pkgs, ... }: {
-        default =
-          let
-            check-nixpkgs-fmt = pkgs.writeShellApplication {
-              name = "check-nixpkgs-fmt";
-              runtimeInputs = with pkgs; [ git nixpkgs-fmt ];
-              text = ''
-                nixpkgs-fmt --check "$(git ls-files '*.nix')"
-              '';
-            };
-            check-rustfmt = pkgs.writeShellApplication {
-              name = "check-rustfmt";
-              runtimeInputs = with pkgs; [ rustToolchain ];
-              text = "cargo fmt --check";
-            };
-            get-ref-statuses = pkgs.writeShellApplication {
-              name = "get-ref-statuses";
-              runtimeInputs = with pkgs; [ rustToolchain ];
-              text = "cargo run --features ref-statuses -- --get-ref-statuses";
-            };
-          in
-          pkgs.mkShell {
-            packages = with pkgs; [
-              bashInteractive
-
-              # Rust
-              rustToolchain
-              cargo-bloat
-              cargo-edit
-              cargo-machete
-              cargo-watch
-              rust-analyzer
-
-              # Nix
-              nixpkgs-fmt
-
-              # CI checks
-              check-nixpkgs-fmt
-              check-rustfmt
-
-              # Scripts
-              get-ref-statuses
-            ];
-
-            env = {
-              # Required by rust-analyzer
-              RUST_SRC_PATH = "${pkgs.rustToolchain}/lib/rustlib/src/rust/library";
+      packages = forAllSystems (
+        { pkgs, system }:
+        rec {
+          default = flake-checker;
+
+          flake-checker = pkgs.naerskLib.buildPackage (
+            {
+              name = "flake-checker";
+              src = self;
+              doCheck = true;
+              nativeBuildInputs = with pkgs; [ ] ++ lib.optionals stdenv.isDarwin [ libiconv ];
+            }
+            // pkgs.lib.optionalAttrs pkgs.stdenv.isLinux {
+              CARGO_BUILD_TARGET =
+                if system == "x86_64-linux" then
+                  "x86_64-unknown-linux-musl"
+                else if system == "aarch64-linux" then
+                  "aarch64-unknown-linux-musl"
+                else
+                  throw "Unsupported Linux system: ${system}";
+              CARGO_BUILD_RUSTFLAGS = "-C target-feature=+crt-static";
+            }
+          );
+        }
+      );
+
+      devShells = forAllSystems (
+        { pkgs, system }:
+        {
+          default =
+            let
+              check-nixpkgs-fmt = pkgs.writeShellApplication {
+                name = "check-nixpkgs-fmt";
+                runtimeInputs = with pkgs; [
+                  git
+                  nixpkgs-fmt
+                ];
+                text = ''
+                  nixpkgs-fmt --check "$(git ls-files '*.nix')"
+                '';
+              };
+              check-rustfmt = pkgs.writeShellApplication {
+                name = "check-rustfmt";
+                runtimeInputs = with pkgs; [ rustToolchain ];
+                text = "cargo fmt --check";
+              };
+              get-ref-statuses = pkgs.writeShellApplication {
+                name = "get-ref-statuses";
+                runtimeInputs = with pkgs; [ rustToolchain ];
+                text = "cargo run --features ref-statuses -- --get-ref-statuses";
+              };
+              update-readme = pkgs.writeShellApplication {
+                name = "update-readme";
+                runtimeInputs = [
+                  inputs.easy-template.packages.${system}.default
+                  pkgs.jq
+                ];
+                text = ''
+                  tmp=$(mktemp -d)
+                  inputs="''${tmp}/template-inputs.json"
+
+                  jq '{supported: .}' ./ref-statuses.json > "''${inputs}"
+                  easy-template ./templates/README.md.handlebars "''${inputs}" > README.md
+
+                  rm -rf "''${tmp}"
+                '';
+              };
+            in
+            pkgs.mkShell {
+              packages = with pkgs; [
+                bashInteractive
+
+                # Rust
+                rustToolchain
+                cargo-bloat
+                cargo-edit
+                cargo-machete
+                cargo-watch
+                rust-analyzer
+
+                # Nix
+                nixpkgs-fmt
+
+                # CI checks
+                check-nixpkgs-fmt
+                check-rustfmt
+
+                # Scripts
+                get-ref-statuses
+                update-readme
+              ];
+
+              env = {
+                # Required by rust-analyzer
+                RUST_SRC_PATH = "${pkgs.rustToolchain}/lib/rustlib/src/rust/library";
+              };
             };
-          };
-      });
+        }
+      );
     };
 }