Add CI

.github/workflows/haskell.yml

@@ -0,0 +1,93 @@
+name: Haskell (build, test, haddock)
+
+# Controls when the workflow will run
+on:
+  push:
+    branches: [main]
+    tags: [v*]
+  pull_request:
+
+  # Allows you to run this workflow manually from the Actions tab
+  workflow_dispatch:
+
+permissions:
+  contents: write # to submit Haddock documentation to GitHub Pages
+
+jobs:
+  tests:
+    name: Run tests
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-latest, windows-latest, macos-12]
+    steps:
+      - name: 📥 Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set codepage on Windows
+        if: ${{ runner.os == 'Windows' }}
+        run: chcp 65001
+
+      - name: Restore Syntax files
+        id: restore-syntax-files
+        uses: actions/cache/restore@v4
+        with:
+          key: syntax-files-${{ runner.os }}-${{ hashFiles(format('{0}.cf', 'haskell/free-foil/src/Language/LambdaPi/Syntax/'), 'stack.yaml.lock') }}
+          path: |
+            haskell/free-foil/src/Language/LambdaPi/Syntax/Lex.hs
+            haskell/free-foil/src/Language/LambdaPi/Syntax/Par.hs
+
+      - name: Check Syntax files exist
+        if: steps.restore-syntax-files.outputs.cache-hit == 'true'
+        shell: bash
+        id: check-syntax-files
+        run: |
+          source scripts/lib.sh
+          check_syntax_files_exist
+          printf "SYNTAX_FILES_EXIST=$SYNTAX_FILES_EXIST\n" >> $GITHUB_OUTPUT
+
+      - name: 🧰 Setup Stack
+        uses: freckle/stack-action@v5
+        with:
+          stack-build-arguments: --pedantic
+          stack-build-arguments-build: --dry-run
+          stack-build-arguments-test: --ghc-options -O2 ${{ steps.check-syntax-files.outputs.SYNTAX_FILES_EXIST == 'true' && ' ' || '--reconfigure --force-dirty --ghc-options -fforce-recomp' }}
+
+      - name: Save Syntax files
+        uses: actions/cache/save@v4
+        if: steps.restore-syntax-files.outputs.cache-hit != 'true'
+        with:
+          key: syntax-files-${{ runner.os }}-${{ hashFiles(format('{0}.cf', 'haskell/free-foil/src/Language/LambdaPi/Syntax/'), 'stack.yaml.lock') }}
+          path: |
+            haskell/free-foil/src/Language/LambdaPi/Syntax/Lex.hs
+            haskell/free-foil/src/Language/LambdaPi/Syntax/Par.hs
+
+  docs:
+    needs: [tests]
+    if: ${{ github.ref_name == 'main' }}
+    name: "Build and upload site (main)"
+    runs-on: ubuntu-latest
+    steps:
+      - name: 📥 Checkout repository
+        uses: actions/checkout@v4
+        with:
+          ref: ${{ github.ref }}
+
+      - name: 🧰 Setup Stack
+        uses: freckle/stack-action@v5
+        with:
+          test: false
+          stack-build-arguments: --fast --haddock
+          cache-prefix: docs-
+
+      - name: Add haddock
+        run: |
+          mkdir -p dist/haddock
+          mv $(stack path --local-doc-root)/* dist/haddock
+
+      - name: 🚀 Publish Site
+        uses: JamesIves/github-pages-deploy-action@v4
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+          folder: dist
+          single-commit: true