Add add-to-path input to control whether the toolchain is added to the PATH

This is useful for cases when testing WasmKit, which requires normal
Swift toolchain to build the project itself, but requires SwiftWasm
toolchain to build fixtures and run tests.

Author: kateinoigakukun

.github/workflows/test.yml

@@ -42,6 +42,27 @@ jobs:
     - uses: actions/checkout@v3
     - uses: ./
     - run: swift --version
+  test-skip-add-to-path:
+    runs-on: ubuntu-22.04
+    steps:
+    - uses: actions/checkout@v3
+    - uses: ./
+      id: setup
+      with:
+        add-to-path: false
+    - name: Ensure that the toolchain is not added to the PATH
+      shell: node {0}
+      run: |
+        const path = require('path');
+        const toolchainPath = path.join(process.env.TOOLCHAIN_PATH, 'usr', 'bin');
+        const pathEnv = process.env.PATH;
+        console.log(`Checking if ${toolchainPath} is in the PATH (${pathEnv})`);
+        const pathCandidates = pathEnv.split(path.delimiter);
+        if (pathCandidates.includes(toolchainPath)) {
+          throw new Error(`Toolchain path ${toolchainPath} is in the PATH`);
+        }
+      env:
+        TOOLCHAIN_PATH: ${{ steps.setup.outputs.toolchain-path }}
   test-nightly:
     runs-on: ubuntu-20.04
     steps:

action.yml

@@ -6,6 +6,9 @@ branding:
 inputs:
   swift-version:
     description: 'Swift version to configure. Reads from .swift-version if unset. Use default value if both are absent.'
+  add-to-path:
+    description: 'Add the toolchain to the PATH'
+    default: 'true'
 runs:
   using: 'node16'
   main: 'dist/index.js'

dist/index.js

@@ -13,7 +13,9 @@ async function run(version) {
   core.debug(`Resolved toolchain download URL: ${url}`);
   const toolchainPath = await installToolchain(url, version, platform);
   core.info(`Toolchain installed at ${toolchainPath}`);
-  core.addPath(`${toolchainPath}/usr/bin`);
+  if (core.getBooleanInput("add-to-path")) {
+    core.addPath(`${toolchainPath}/usr/bin`);
+  }
   core.setOutput("toolchain-path", toolchainPath);
 }
 

dist/index.js.map

@@ -7,6 +7,9 @@ inputs:
   token:
     description: Personal access token (PAT) used to fetch releases.
     default: ${{ github.token }}
+  add-to-path:
+    description: 'Add the toolchain to the PATH'
+    default: 'true'
 runs:
   using: 'node16'
   main: '../dist/nightly/index.js'