Use HLint action for CI (#42)

* Use HLint action for CI

* Split linting and styling, use Fourmolu

.github/workflows/ci.yml

@@ -1,4 +1,4 @@
-name: CI
+name: Tests
 
 # Trigger the workflow on push or pull request, but only for the main branch
 on:
@@ -30,7 +30,6 @@ jobs:
           echo "/nix/var/nix/profiles/default/bin" >> "$GITHUB_PATH"
           echo "NIX_SSL_CERT_FILE=$cert_file" >> "$GITHUB_ENV"
           cert_file=/nix/var/nix/profiles/default/etc/ssl/certs/ca-bundle.crt
-          env
 
     - name: Configure Darwin Nixpkgs
       if: matrix.os == 'macos-latest' 
@@ -70,12 +69,6 @@ jobs:
     - name: Installing dependencies 
       run: nix-shell --pure -I ${{ env.NIX_PATH }} --argstr ghcVersion ${{env.GHC}} --run 'make deps' .github/workflows/shell.nix
 
-    - name: Running hlint
-      run: nix-shell --pure -I ${{ env.NIX_PATH }} --argstr ghcVersion ${{env.GHC}} --run './.github/workflows/hlint-runner.sh' .github/workflows/shell.nix
-
-    - name: Running stylish-haskell
-      run: nix-shell --pure -I ${{ env.NIX_PATH }} --argstr ghcVersion ${{env.GHC}} --run './.github/workflows/stylish-haskell-runner.sh' .github/workflows/shell.nix
-
     - name: Build
       run: nix-shell --pure -I ${{ env.NIX_PATH }} --argstr ghcVersion ${{env.GHC}} --run 'make build' .github/workflows/shell.nix
 

.github/workflows/stylish-haskell-runner.sh → .github/workflows/fourmolu-runner.sh

@@ -4,7 +4,7 @@ set -eux
 
 git add .
 
-stylish-haskell -c .stylish-haskell.yaml -r src test app -i
+fourmolu --mode check $(git ls-files '*.hs')
 
 git status
 

.github/workflows/linting.yml

@@ -0,0 +1,48 @@
+name: Linting
+
+on:
+  pull_request:
+  push:
+    branches: ["main", "development"]
+
+jobs:
+  hlint:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+
+    - name: 'Set up HLint'
+      uses: rwe/actions-hlint-setup@v1
+      with:
+        version: '3.3.6'
+
+    - name: 'Run HLint'
+      uses: rwe/actions-hlint-run@v1
+      with:
+        path: '["src/", "test/"]'
+        fail-on: warning
+
+  styling:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+    - name: Configure environment
+
+    - name: Set up Haskell
+      id: setup-haskell
+      uses: haskell/actions/setup@v1
+      with:
+        ghc-version: "8.10.7"
+        cabal-version: "latest"
+
+
+    - name: Install tools
+      run: |
+        cd ~/
+        echo "$HOME/.ghcup/bin" >> $GITHUB_PATH
+        echo "$HOME/.cabal/bin" >> $GITHUB_PATH
+        echo "$HOME/.local/bin" >> $GITHUB_PATH
+        cabal install -j fourmolu
+
+    - name: Running fourmolu
+      run: ./.github/workflows/fourmolu-runner.sh

fourmolu.yaml

@@ -0,0 +1,9 @@
+indentation: 2
+comma-style: leading # for lists, tuples etc. - can also be 'leading'
+import-export-comma-style: leading # for module import export lists - can also be 'leading'
+record-brace-space: false # rec {x = 1} vs. rec{x = 1}
+indent-wheres: true # 'false' means save space by only half-indenting the 'where' keyword
+diff-friendly-import-export: false # 'false' uses Ormolu-style lists
+respectful: true # don't be too opinionated about newlines etc.
+haddock-style: multi-line # '--' vs. '{-'
+newlines-between-decls: 1 # number of newlines between top-level declarations

shell.nix

@@ -18,7 +18,7 @@ in with pkgs;
       hlint
       cacert
       haskellPackages.apply-refact
-      stylish-haskell
+      fourmolu_0_6_0_0
       git
       haskellPackages.cabal-fmt