Use experimental ghcup in CI

Author: hasufell

.github/workflows/test.yml

@@ -9,6 +9,7 @@ on:
 jobs:
   build:
     strategy:
+      fail-fast: false
       matrix:
         os: [macos-11, ubuntu-latest, windows-latest]
         ghc: [9.0.1, 8.10.4]
@@ -26,15 +27,31 @@ jobs:
         with:
           ghc-version: ${{ matrix.ghc }}
           run: xvfb-run -s '-screen 0 640x480x16' -a npm test
+      - name: "Install ghcup on linux"
+        if: runner.os == 'Linux'
+        run: |
+          curl -O https://downloads.haskell.org/ghcup/0.1.17.6-alpha3/x86_64-linux-ghcup-0.1.17.6
+          chmod +x x86_64-linux-ghcup-0.1.17.6
+          cp x86_64-linux-ghcup-0.1.17.6 "$(which ghcup)"
       - name: "Install `tree` for MacOs"
         run: |
+          curl -O https://downloads.haskell.org/ghcup/0.1.17.6-alpha3/x86_64-apple-darwin-ghcup-0.1.17.6
+          chmod +x x86_64-apple-darwin-ghcup-0.1.17.6
+          cp x86_64-apple-darwin-ghcup-0.1.17.6 "$(which ghcup)"
           brew update
           brew install tree
         if: runner.os == 'macOS'
       - name: "Install `tree` for Windows"
         run: |
           choco install tree
         if: runner.os == 'Windows'
+      - name: "Install ghcup"
+        run: |
+          curl -O https://downloads.haskell.org/ghcup/0.1.17.6-alpha3/x86_64-mingw64-ghcup-0.1.17.6.exe
+          chmod +x x86_64-mingw64-ghcup-0.1.17.6.exe
+          cp x86_64-mingw64-ghcup-0.1.17.6.exe /c/ghcup/bin/ghcup.exe
+        if: runner.os == 'Windows'
+        shell: bash
       # Pre-fetch HLS binaries before the tests because otherwise
       # we run into timeouts. Downloading takes longer, since we download
       # per HLS version one HLS binary per GHC version.