ci: Install lua-compat-5.3 on lua5.1 thru lua5..5

Author: cclauss

.github/workflows/compat53-tests.yml

@@ -68,3 +68,32 @@ jobs:
       - name: compare script output
         run: diff old.txt new.txt || true
 
+  compat53-install:
+    strategy:
+      fail-fast: false  # https://github.com/actions/runner-images#available-images
+      matrix:  # https://www.lua.org/versions.html
+        os: [ubuntu-latest]
+        lua-version: [5.1, 5.2, 5.3, 5.4, 5.5]
+        include:
+          - os: macos-latest
+            lua-version: 5.1
+          - os: macos-latest
+            lua-version: 5.5
+    runs-on: ${{ matrix.os }}
+    steps:
+      - run: echo "${{ runner.os }} on ${{ runner.arch }}"
+      - uses: actions/checkout@v7
+      - uses: luarocks/gh-actions-lua@master
+        with:
+          luaVersion: ${{ matrix.lua-version }}
+      - uses: luarocks/gh-actions-luarocks@master
+        with:
+          luaRocksVersion: "3.13.0"
+      - run: lua -v && luarocks --version
+      # Install the local version of compat53.
+      - run: luarocks --local make rockspecs/compat53-scm-1.rockspec
+      - run: luarocks list && luarocks show compat53
+      - run: luarocks --local remove compat53
+      # Install the public version of compat53.
+      - run: luarocks install --check-lua-versions compat53
+      - run: luarocks list && luarocks show compat53