feat(yarn2-install): allow using no lockfile

README.md

@@ -152,7 +152,7 @@ For use with Yarn 1.
 
 #### yarn2-install
 
-For use with Yarn 2 (berry).
+For use with Yarn 2 (berry). If your project does not use a lockfile, pass `no-lockfile: true`.
 
 [Source](yarn2-install/action.yml)
 
@@ -168,6 +168,7 @@ For use with Yarn 2 (berry).
   with:
     node-version: 18
     yarn-args: --immutable --immutable-cache
+    no-lockfile: true
 ```
 
 ##### Inputs
@@ -176,6 +177,7 @@ For use with Yarn 2 (berry).
 |----------|----------------|------------------------------------|---------------------------------|---------|
 | No       | `node-version` | The Node.js version to use         | `18`                            | `18`    |
 | No       | `yarn-args`    | Arguments to use with yarn install | `--immutable --immutable-cache` | ` `     |
+| No       | `no-lockfile`  | Do not look for yarn.lock          | `true`                          | `false` |
 
 #### pnpm-install
 

yarn2-install/action.yml

@@ -12,6 +12,11 @@ inputs:
     default: ''
     required: false
 
+  no-lockfile:
+    description: 'Do not look for yarn.lock'
+    default: 'false'
+    required: false
+
 runs:
   using: composite
   steps:
@@ -24,11 +29,21 @@ runs:
       run: echo "dir=$(yarn config get cacheFolder)" >> $GITHUB_OUTPUT
       shell: bash
 
+    - name: 'Calculate hash'
+      id: calculate-hash
+      shell: bash
+      run: |
+        if [ "${{ inputs.no-lockfile }}" = "true" ]; then
+          echo "hash=${{ hashFiles('.yarnrc.yml') }}" >> $GITHUB_OUTPUT
+        else
+          echo "hash=${{ hashFiles('.yarnrc.yml', '**/yarn.lock') }}" >> $GITHUB_OUTPUT
+        fi
+
     - name: 'Restore yarn cache'
       uses: actions/cache@v3
       with:
         path: ${{ steps.find-cache-dir.outputs.dir }}
-        key: ${{ runner.os }}-yarn2-${{ hashFiles('**/yarn.lock', '.yarnrc.yml') }}
+        key: ${{ runner.os }}-yarn2-${{ steps.calculate-hash.outputs.hash }}
         restore-keys: |
           ${{ runner.os }}-yarn2-