refactor: add hspec, nix, and switch to cabal

+ Use hspec with the existing golden tests
+ Use cabal instead of stack, and give deps some sensible constraints
+ Use nix flake to get cabal, ghc, etc.

Author: rasheedja

.github/workflows/haskell.yml

@@ -2,22 +2,18 @@ name: Haskell CI
 
 on:
   push:
-    branches:
-      - '*'
-  pull_request:
-    branches: [ "master" ]
+  workflow_dispatch:
 
 permissions:
   contents: read
 
 jobs:
   fourmolu:
-
     runs-on: ubuntu-latest
-  
+
     steps:
-      - uses: actions/checkout@v3
-      - uses: haskell-actions/run-fourmolu@v9
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+      - uses: haskell-actions/run-fourmolu@3b7702b41516aa428dfe6e295dc73476ae58f69e # v11
         with:
           version: "0.14.0.0"
   build:
@@ -27,104 +23,58 @@ jobs:
       fail-fast: false
       matrix:
         os: [windows-latest, macos-latest, ubuntu-latest]
-        ghc-version: ['9.6', '9.4', '9.2', '9.0']
+        ghc-version: ["9.12", "9.10", "9.8", "9.6", "9.4", "9.2"]
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
 
       - name: Set up GHC ${{ matrix.ghc-version }}
-        uses: haskell/actions/setup@v2
+        uses: haskell-actions/setup@96f3dafd067155f32643c2a0757ab71d2910e2c2 # v2.8.0
         id: setup
         with:
           ghc-version: ${{ matrix.ghc-version }}
-          enable-stack: true
 
       - name: Installed minor versions of GHC, Cabal, and Stack
         shell: bash
         run: |
           GHC_VERSION=$(ghc --numeric-version)
           CABAL_VERSION=$(cabal --numeric-version)
-          STACK_VERSION=$(stack --numeric-version)
           echo "GHC_VERSION=${GHC_VERSION}"     >> "${GITHUB_ENV}"
           echo "CABAL_VERSION=${CABAL_VERSION}" >> "${GITHUB_ENV}"
-          echo "STACK_VERSION=${STACK_VERSION}" >> "${GITHUB_ENV}"
+
+      - name: Check cabal file
+        run: cabal check
 
       - name: Configure the build
         run: |
-          # cabal configure --enable-tests --enable-benchmarks --disable-documentation
-          # cabal build --dry-run
-          stack build --test --bench --no-haddock --dry-run
-        # The last step generates dist-newstyle/cache/plan.json for the cache key.
-
-      - name: Restore .stack-work cache
-        uses: actions/cache/restore@v3
-        id: cache-restore-stack-work
-        with:
-          path: .stack-work
-          key: ${{ runner.os }}-ghc-${{ env.GHC_VERSION }}-stack-${{ env.STACK_VERSION }}-stack-work-${{ hashFiles('stack.yaml') }}-${{ hashFiles('package.yaml') }}-${{ hashFiles('**/*.hs') }}
-          restore-keys: |
-            ${{ runner.os }}-ghc-${{ env.GHC_VERSION }}-stack-${{ env.STACK_VERSION }}-stack-work-
-      
-      - name: Restore ~/.stack cache (Unix)
-        uses: actions/cache/restore@v3
-        id: cache-restore-stack-global-unix
-        if: runner.os == 'Linux' || runner.os == 'macOS'
-        with:
-          path: ~/.stack
-          key: ${{ runner.os }}-ghc-${{ env.GHC_VERSION }}-stack-${{ env.STACK_VERSION }}-stack-global-${{ hashFiles('stack.yaml') }}-${{ hashFiles('package.yaml') }}
-          restore-keys: |
-            ${{ runner.os }}-ghc-${{ env.GHC_VERSION }}-stack-${{ env.STACK_VERSION }}-stack-global-
-
-      - name: Restore %APPDATA%\stack, %LOCALAPPDATA%\Programs\stack cache (Windows)
-        uses: actions/cache/restore@v3
-        id: cache-restore-stack-global-windows
-        if: runner.os == 'Windows'
+          cabal configure --enable-tests --enable-benchmarks --disable-documentation
+          cabal build --dry-run
+
+      - name: Restore cached dependencies
+        uses: actions/cache/restore@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+        id: cache
+        env:
+          key: ${{ runner.os }}-ghc-${{ steps.setup.outputs.ghc-version }}-cabal-${{ steps.setup.outputs.cabal-version }}
         with:
-          path: |
-            ~\AppData\Roaming\stack
-            ~\AppData\Local\Programs\stack    
-          key: ${{ runner.os }}-ghc-${{ env.GHC_VERSION }}-stack-${{ env.STACK_VERSION }}-stack-global-${{ hashFiles('stack.yaml') }}-${{ hashFiles('package.yaml') }}
-          restore-keys: |
-            ${{ runner.os }}-ghc-${{ env.GHC_VERSION }}-stack-${{ env.STACK_VERSION }}-stack-global-
+          path: ${{ steps.setup.outputs.cabal-store }}
+          key: ${{ env.key }}-plan-${{ hashFiles('**/plan.json') }}
+          restore-keys: ${{ env.key }}-
 
       - name: Build dependencies
-        run: stack build --only-dependencies
+        run: cabal build --only-dependencies
 
-      - name: Build the package
-        run: stack build
-
-      - name: Save .stack-work cache
-        uses: actions/cache/save@v3
-        id: cache-save-stack-work
-        if: steps.cache-restore-stack-work.outputs.cache-hit != 'true'
-        with:
-          path: .stack-work
-          key: ${{ steps.cache-restore-stack-work.outputs.cache-primary-key }}
-   
-      - name: Save %APPDATA%\stack, %LOCALAPPDATA%\Programs\stack cache (Windows)
-        uses: actions/cache/save@v3
-        if: runner.os == 'Windows'
-            && steps.cache-restore-stack-global-windows.outputs.cache-hit != 'true'
+      - name: Save cached dependencies
+        uses: actions/cache/save@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+        if: steps.cache.outputs.cache-hit != 'true'
         with:
-          path: |
-            ~\AppData\Roaming\stack
-            ~\AppData\Local\Programs\stack    
-          key: ${{ steps.cache-restore-stack-global-windows.outputs.cache-primary-key }}
-  
-      - name: Save ~/.stack cache (Unix)
-        uses: actions/cache/save@v3
-        id: cache-save-stack-global
-        if: (runner.os == 'Linux' || runner.os == 'macOS') 
-            && steps.cache-restore-stack-global-unix.outputs.cache-hit != 'true'
-        with:
-          path: ~/.stack
-          key: ${{ steps.cache-restore-stack-global-unix.outputs.cache-primary-key }}
+          path: ${{ steps.setup.outputs.cabal-store }}
+          key: ${{ steps.cache.outputs.cache-primary-key }}
 
-      - name: Run tests
-        run: stack test
+      - name: Build the package
+        run: cabal build all
 
-      - name: Check cabal file
-        run: cabal check
+      - name: Run tests
+        run: cabal test all
 
       - name: Build documentation
-        run: stack haddock
+        run: cabal haddock all --disable-documentation

ChangeLog.md

@@ -2,6 +2,9 @@
 
 ## Unreleased changes
 
+- Use Hspec for tests
+- Add nix flake
+
 ## [v0.2.0.0](https://github.com/rasheedja/LPPaver/tree/v0.2.0.0)
 
 - Setup CI