Add feature of prefering already installed versions

.github/workflows/test-dotnet.yml

@@ -41,3 +41,25 @@ jobs:
         shell: pwsh
         run: |
           __tests__/verify-dotnet.ps1 -Patterns "^${{ matrix.dotnet-version }}"
+  setup-versions-prefer-installed:
+    runs-on: ${{ matrix.operating-system }}
+    strategy:
+      fail-fast: false
+      matrix:
+        operating-system: [ubuntu-latest, windows-latest, macOS-latest]
+        dotnet-version: ['2.1', '2.2', '3.0', '3.1', '5.0', '6.0', '7.0', '8.0']
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Clear toolcache
+        shell: pwsh
+        run: __tests__/clear-toolcache.ps1 ${{ runner.os }}
+      - name: Setup dotnet ${{ matrix.dotnet-version }}
+        uses: ./
+        with:
+          dotnet-version: ${{ matrix.dotnet-version }}
+          prefer-installed: true
+      - name: Verify installed version
+        shell: pwsh
+        run: |
+          __tests__/verify-dotnet.ps1 -Patterns "^${{ matrix.dotnet-version }}"

action.yml

@@ -9,6 +9,10 @@ inputs:
     description: 'Optional SDK version(s) to use. If not provided, will install global.json version when available. Examples: 2.2.104, 3.1, 3.1.x, 3.x, 6.0.2xx'
   dotnet-quality:
     description: 'Optional quality of the build. The possible values are: daily, signed, validated, preview, ga.'
+  prefer-installed:
+    description: 'Optional flag to prefer an already installed version of the SDK (when partial version syntax is used). If not provided, latest version with specified quality will be installed.'
+    required: false
+    default: false
   global-json-file:
     description: 'Optional global.json location, if your global.json isn''t located in the root of the repo.'
   source-url: