feat: read pnpm version from devEngines.packageManager field

When no version is specified in the action config or the packageManager
field of package.json, fall back to devEngines.packageManager.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

action.yml

@@ -37,6 +37,6 @@ outputs:
   bin_dest:
     description: Location of `pnpm` and `pnpx` command
 runs:
-  using: node20
+  using: node24
   main: dist/index.js
   post: dist/index.js

package.json

@@ -12,7 +12,7 @@
     "@actions/exec": "^1.1.1",
     "@actions/glob": "^0.5.0",
     "@types/expand-tilde": "^2.0.2",
-    "@types/node": "^20.11.5",
+    "@types/node": "^22.0.0",
     "expand-tilde": "^2.0.2",
     "yaml": "^2.3.4",
     "zod": "^3.22.4"

pnpm-lock.yaml

@@ -24,8 +24,8 @@ importers:
         specifier: ^2.0.2
         version: 2.0.2
       '@types/node':
-        specifier: ^20.11.5
-        version: 20.17.17
+        specifier: ^22.0.0
+        version: 22.19.11
       expand-tilde:
         specifier: ^2.0.2
         version: 2.0.2
@@ -137,8 +137,8 @@ packages:
   '@types/expand-tilde@2.0.2':
     resolution: {integrity: sha512-wlsMYiapmIR4Eq/Z0qysN8xaDMjSkO6AIDNFx9oxgWGeKVA1jU+NzwPRZErBNP5z6/dx6QNkNpKglBGPO9OkTA==}
 
-  '@types/node@20.17.17':
-    resolution: {integrity: sha512-/WndGO4kIfMicEQLTi/mDANUu/iVUhT7KboZPdEqqHQ4aTS+3qT3U5gIqWDFV+XouorjfgGqvKILJeHhuQgFYg==}
+  '@types/node@22.19.11':
+    resolution: {integrity: sha512-BH7YwL6rA93ReqeQS1c4bsPpcfOmJasG+Fkr6Y59q83f9M1WcBRHR2vM+P9eOisYRcN3ujQoiZY8uk5W+1WL8w==}
 
   '@typespec/ts-http-runtime@0.3.0':
     resolution: {integrity: sha512-sOx1PKSuFwnIl7z4RN0Ls7N9AQawmR9r66eI5rFCzLDIs8HTIYrIpH9QjYWoX0lkgGrkLxXhi4QnK7MizPRrIg==}
@@ -335,8 +335,8 @@ packages:
     engines: {node: '>=14.17'}
     hasBin: true
 
-  undici-types@6.19.8:
-    resolution: {integrity: sha512-ve2KP6f/JnbPBFyobGHuerC9g1FYGn/F8n1LWTwNxCEzd6IfqTwUQcNXgEtmmQ6DlRrC1hrSrBnCZPokRrDHjw==}
+  undici-types@6.21.0:
+    resolution: {integrity: sha512-iwDZqg0QAGrg9Rav5H4n0M64c3mkR59cJ6wQp+7C4nI0gsmExaedaYLNO44eT4AtBBwjbTiGPMlt2Md0T9H9JQ==}
 
   undici@5.29.0:
     resolution: {integrity: sha512-raqeBD6NQK4SkWhQzeYKd1KmIG6dllBOTt55Rmkt4HtI9mwdWtJljnrXjAFUBLTSN67HWrOIZ3EPF4kjUw80Bg==}
@@ -539,9 +539,9 @@ snapshots:
 
   '@types/expand-tilde@2.0.2': {}
 
-  '@types/node@20.17.17':
+  '@types/node@22.19.11':
     dependencies:
-      undici-types: 6.19.8
+      undici-types: 6.21.0
 
   '@typespec/ts-http-runtime@0.3.0':
     dependencies:
@@ -717,7 +717,7 @@ snapshots:
 
   typescript@5.7.3: {}
 
-  undici-types@6.19.8: {}
+  undici-types@6.21.0: {}
 
   undici@5.29.0:
     dependencies:

src/install-pnpm/run.ts

@@ -57,21 +57,28 @@ async function readTarget(opts: {
   const { version, packageJsonFile, standalone } = opts
   const { GITHUB_WORKSPACE } = process.env
 
-  let packageManager
+  let packageManager: string | undefined
+  let devEngines: { packageManager?: { name?: string; version?: string } } | undefined
 
   if (GITHUB_WORKSPACE) {
     try {
       const content = readFileSync(path.join(GITHUB_WORKSPACE, packageJsonFile), 'utf8');
-      ({ packageManager } = packageJsonFile.endsWith(".yaml")
+      const manifest = packageJsonFile.endsWith(".yaml")
         ? parseYaml(content, { merge: true })
         : JSON.parse(content)
-      )
+      packageManager = manifest.packageManager
+      devEngines = manifest.devEngines
     } catch (error: unknown) {
       // Swallow error if package.json doesn't exist in root
       if (!util.types.isNativeError(error) || !('code' in error) || error.code !== 'ENOENT') throw error
     }
   }
 
+  // If packageManager field is not set, try devEngines.packageManager
+  if (typeof packageManager !== 'string' && devEngines?.packageManager?.name === 'pnpm' && devEngines.packageManager.version) {
+    packageManager = `pnpm@${devEngines.packageManager.version}`
+  }
+
   if (version) {
     if (
       typeof packageManager === 'string' &&
@@ -98,7 +105,8 @@ Otherwise, please specify the pnpm version in the action configuration.`)
     throw new Error(`No pnpm version is specified.
 Please specify it by one of the following ways:
   - in the GitHub Action config with the key "version"
-  - in the package.json with the key "packageManager"`)
+  - in the package.json with the key "packageManager"
+  - in the package.json with the key "devEngines.packageManager"`)
   }
 
   if (!packageManager.startsWith('pnpm@')) {