Add a 'source-root' input to the init Action

.github/workflows/pr-checks.yml

@@ -894,3 +894,25 @@ jobs:
     - name: Build code
       run: ./build.sh
     - uses: ./../action/analyze
+
+  test-javascript-source-root:
+    needs: [check-js, check-node-modules]
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+    - uses: ./init
+      with:
+        languages: javascript
+        source-root: tests/multi-language-repo
+    - uses: ./analyze
+      with:
+        skip-queries: true
+        upload: false
+    - name: Assert database exists
+      run: |
+        cd "$RUNNER_TEMP/codeql_databases"
+        if [[ ! -d javascript ]]; then
+          echo "Did not find a JavaScript database"
+          exit 1
+        fi

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ## [UNRELEASED]
 
+- The `init` step of the Action now supports a `source-root` input as a path to the root source-code directory. By default, the path is relative to $GITHUB_WORKSPACE. [#607](https://github.com/github/codeql-action/pull/607)
 - The `analyze` step of the Action now supports a `skip-queries` option to merely build the CodeQL database without analyzing. This functionality is not present in the runner. Additionally, the step will no longer fail if it encounters a finalized database, and will instead continue with query execution. [#602](https://github.com/github/codeql-action/pull/602)
 - Update the warning message when the baseline lines of code count is unavailable. [#608](https://github.com/github/codeql-action/pull/608)
 

init/action.yml

@@ -38,6 +38,9 @@ inputs:
     description: Try to auto-install your python dependencies
     required: true
     default: 'true'
+  source-root:
+    description: Path of the root source code directory, relative to $GITHUB_WORKSPACE.
+    required: false
 outputs:
   codeql-path:
     description: The path of the CodeQL binary used for analysis