Add Haskell CI for GitHub Actions

.github/workflows/haskell.yml

@@ -0,0 +1,78 @@
+name: Haskell CI
+
+on:
+  push:
+    branches: [ "master" ]
+  pull_request:
+    branches: [ "master" ]
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    name: GHC ${{ matrix.ghc-version }} on ${{ matrix.os }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest]
+        ghc-version: ['9.6', '9.4', '9.2']
+
+        include:
+          - os: windows-latest
+            ghc-version: '9.6'
+          - os: macos-latest
+            ghc-version: '9.6'
+
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Set up GHC ${{ matrix.ghc-version }}
+        uses: haskell-actions/setup@v2
+        id: setup
+        with:
+          ghc-version: ${{ matrix.ghc-version }}
+          # Defaults, added for clarity:
+          cabal-version: 'latest'
+          cabal-update: true
+
+      - name: Configure the build
+        run: |
+          cabal configure --enable-tests --enable-benchmarks --disable-documentation
+          cabal build --dry-run
+        # The last step generates dist-newstyle/cache/plan.json for the cache key.
+
+      - name: Restore cached dependencies
+        uses: actions/cache/restore@v3
+        id: cache
+        env:
+          key: ${{ runner.os }}-ghc-${{ steps.setup.outputs.ghc-version }}-cabal-${{ steps.setup.outputs.cabal-version }}
+        with:
+          path: ${{ steps.setup.outputs.cabal-store }}
+          key: ${{ env.key }}-plan-${{ hashFiles('**/plan.json') }}
+          restore-keys: ${{ env.key }}-
+
+      - name: Install dependencies
+        run: cabal build all --only-dependencies
+
+      # Cache dependencies already here, so that we do not have to rebuild them should the subsequent steps fail.
+      - name: Save cached dependencies
+        uses: actions/cache/save@v3
+        # Caches are immutable, trying to save with the same key would error.
+        if: ${{ steps.cache.outputs.cache-primary-key != steps.cache.outputs.cache-matched-key }}
+        with:
+          path: ${{ steps.setup.outputs.cabal-store }}
+          key: ${{ steps.cache.outputs.cache-primary-key }}
+
+      - name: Build
+        run: cabal build all
+
+      - name: Run tests
+        run: cabal test all
+
+      - name: Check cabal file
+        run: cabal check
+
+      - name: Build documentation
+        run: cabal haddock all

binder.cabal

@@ -16,6 +16,10 @@ homepage:           https://github.com/ijaketak/binder
 category:           Data
 build-type:         Simple
 extra-doc-files:    CHANGELOG.md
+tested-with:
+      GHC == 9.2.8
+    , GHC == 9.4.7
+    , GHC == 9.6.3
 -- extra-source-files:
 
 common depends
@@ -34,7 +38,7 @@ library
     -- other-modules:
     -- other-extensions:
     build-depends:
-          base ^>=4.17.2.0
+          base >= 4.16.0.0
         , lens
     hs-source-dirs:   src
     default-language: Haskell2010
@@ -50,7 +54,7 @@ test-suite binder-test
     hs-source-dirs:   test
     main-is:          Spec.hs
     build-depends:
-          base ^>=4.17.2.0
+          base >= 4.16.0.0
         , binder
         , hspec
     build-tool-depends: hspec-discover:hspec-discover