Add support for exact GHC versions

.gitattributes

@@ -0,0 +1 @@
+/dist/** -diff linguist-generated=true

.github/workflows/selftest.yml

@@ -0,0 +1,74 @@
+name: build
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+  schedule:
+    - cron: 0 0 * * *
+
+jobs:
+  build:
+    name: ${{ matrix.os }} / GHC ${{ matrix.ghc }}
+    runs-on: ${{ matrix.os }}
+
+    strategy:
+      matrix:
+        os:
+          - ubuntu-18.04
+        ghc:
+          - 7.0.1
+          - 7.0.4
+          - 7.2.2
+          - 7.4.1
+          - 7.4.2
+          - 7.6.3
+          - 7.8.4
+          - 7.10.3
+          - 8.0.2
+          - 8.2.2
+          - 8.4.1
+          - 8.4.2
+          - 8.4.3
+          - 8.4.4
+          - 8.6.1
+          - 8.6.2
+          - 8.6.3
+          - 8.6.4
+          - 8.6.5
+          - 8.8.1
+          - 8.8.2
+          - 8.8.3
+          - 8.8.4
+          - 8.10.1
+          - 8.10.2
+          - 8.10.3
+          - 8.10.4
+          - 8.10.5
+          - 8.10.6
+          - 8.10.7
+          - 9.0.1
+          - 9.0.2
+          - 9.2.1
+          - 9.2.2
+
+    steps:
+      - uses: actions/checkout@v3
+      - name: setup-haskell
+        uses: ./
+        with:
+          ghc-version: ${{ matrix.ghc }}
+
+      - run: ghc --version
+
+  success:
+    needs: build
+    runs-on: ubuntu-latest
+    if: always() # this is required as GitHub considers "skipped" jobs as "passed" when checking branch protection rules
+
+    steps:
+      - run: exit 1
+        if: needs.build.result != 'success'

LICENSE

@@ -0,0 +1,19 @@
+Copyright (c) 2022 Simon Hengel <[email protected]>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

action.yml

@@ -0,0 +1,8 @@
+name: Setup Haskell
+author: Simon Hengel
+inputs:
+  ghc-version:
+    required: true
+runs:
+  using: node16
+  main: dist/index.js