Switch CI to use nix flake

.github/workflows/main.yml

@@ -1,46 +1,14 @@
-name: "Build"
-
-permissions:
-  contents: read
-  pages: write
-  id-token: write
-
+name: "Test"
 on:
-  push:
-    branches: [ "main" ]
   pull_request:
-    branches: [ "main" ]
-
-  # Allows you to run this workflow manually from the Actions tab
-  workflow_dispatch:
-
+  push:
 jobs:
-  build:
+  tests:
     runs-on: ubuntu-latest
-    container:
-      image: "docker://ghcr.io/chrisdone/hell-build:2025-03-04@sha256:ca21e3be038cf1f10fa18306123b4d5f0e2009fe8938cea3afcef7f900bbea71"
-
-      env:
-        # For the ~/.stack root.
-        HOME: /root/
-        STACK_ROOT: /root/.stack
-
-        # This can be both of these, depending on whether it's a PR or
-        # main. GitHub Actions is weird.
-        #
-        # * "GIT_BRANCH=refs/heads/main"
-        # * "GIT_BRANCH=cd/2024-08-28-check-examples"
-        #
-        GIT_BRANCH: ${{ github.head_ref || github.ref }}
-
     steps:
-      - run: |
-          git clone https://github.com/chrisdone/hell /tmp/hell && \
-          cd /tmp/hell && \
-          git checkout $GIT_BRANCH
-      - run: |
-          cd /tmp/hell && stack build --fast
-      - run: |
-          cd /tmp/hell && stack exec hell scripts/check-examples.hell
-      - run: |
-          cd /tmp/hell && HOME=/home/chris/ stack exec hell scripts/check-docs.hell
+    - uses: actions/checkout@v5
+    - uses: cachix/install-nix-action@v31
+      with:
+        github_access_token: ${{ secrets.GITHUB_TOKEN }}
+    - run: nix build
+    - run: nix flake check

flake.nix

@@ -41,6 +41,15 @@
             pkgs.zlib
           ];
         };
+        checks = {
+          run-script-check = pkgs.runCommand "test-hell-script" {
+            buildInputs = [ app ];
+          } ''
+            hell ${./scripts/check.hell} --dir ${./examples} --dir ${./scripts}
+            touch $out
+          '';
+          build = app;
+        };
         packages = {
           default = app;
           static-arm64 = mkStaticApp pkgsStaticArm64;

scripts/check.hell

@@ -1,22 +1,24 @@
 data Opts = Opts {
+  dirs :: [Text],
   compilerStats :: Bool
   }
 
 options =
-  (\compilerStats -> Main.Opts { compilerStats })
-     <$> Options.switch (Flag.long "compiler-stats" <> Flag.help "Pass --compiler-stats in?")
+  (\dirs compilerStats -> Main.Opts { compilerStats, dirs })
+     <$> Alternative.many (Options.strOption (Option.long "dir" <> Option.help "Directory to check"))
+     <*> Options.switch (Flag.long "compiler-stats" <> Flag.help "Pass --compiler-stats in?")
 
 main = do
   opts <- Options.execParser (Options.info (Main.options <**> Options.helper) Options.fullDesc)
   let extra = if Record.get @"compilerStats" opts
                  then ["--compiler-stats"]
                  else []
+  let dirs = Record.get @"dirs" opts
   let list = \dir ->
-        Functor.fmap (List.filter (Text.isSuffixOf ".hell") . List.map (\x -> dir <> x))
+        Functor.fmap (List.filter (Text.isSuffixOf ".hell") . List.map (\x -> dir <> "/" <> x))
           $ Directory.listDirectory dir
-  examples <- list "examples/"
-  scripts <- list "scripts/"
-  Async.pooledForConcurrently (examples <> scripts) \fp -> do
+  examples <- Functor.fmap List.concat $ Monad.mapM list dirs
+  Async.pooledForConcurrently examples \fp -> do
     Text.putStrLn $ Text.concat ["Checking ", fp]
     Process.runProcess_ (Process.proc "hell" (["--check", fp] <> extra))
   Text.putStrLn "All OK."

src/Hell.hs

@@ -2147,6 +2147,7 @@ polyLits =
 
                -- Alternative operations
                "Alternative.optional" (optional) :: forall (f :: Type -> Type) a. (Alternative f) => f a -> f (Maybe a)
+               "Alternative.many" (many) :: forall (f :: Type -> Type) a. (Alternative f) => f a -> f [a]
 
                -- Monadic operations
                "Monad.mapM_" mapM_ :: forall a (m :: Type -> Type). (Monad m) => (a -> m ()) -> [a] -> m ()