Dependencies are still installed after cache flag is true

Description: Yarn still installs dependencies even though cache flag is true. Tested on hosted ubuntu-latest env and on self-hosted macOS env.

Action version: Specify the action version actions/checkout@v2

Platform:

• Ubuntu
• macOS
• Windows

Runner type:

• Hosted
• Self-hosted

Tools version:

yarn v1.22.15

Repro steps:
A description with steps to reproduce the issue. If your have a public example or repo to share, please provide the link.

name: unit-tests
on:
  workflow_dispatch

jobs:
  test:
    name: Cache deps
    runs-on: ubuntu-latest

    steps:
      - name: Checkout mobile-react
        uses: actions/checkout@v2

      - name: Set up Node with cache
        uses: actions/setup-node@v2
        with:
          node-version: 14
          cache: 'yarn'

      - name: Install yarn dependencies
        timeout-minutes: 5
        run: yarn install

Expected behavior: After cache is applied yarn install should be skipped.

Actual behavior: After cache is applied yarn installs dependencies .

[akmjenkins]

the action will save global cache for yarn or npm.

AHHHH, now I got it. This is why it still takes 40 seconds or so. The modules are all cached (when I specified cache: 'yarn', but they’re in the global cache, yarn still needs to fetch them (but it won’t go online, it’ll find them from the global cache) and resolve them to the local node_modules folder.

Thank you so much for spelling this out for me 🙏🏼 🙏🏼 🙏🏼

[dmitry-shibanov]

Hello @akmjenkins. Hosted images have precached versions of Nodejs. If version does not exist on the image, it will be downloaded and precached. If you use self-hosted runners Nodejs versions will be saved. Hosted runners are cleaned at the end of the job, so saved nodejs versions won’t be saved for future runs. If you specify npm or yarn, the action will save global cache for yarn or npm. The cache for yarn and npm is located in different places.

• For yarn the action uses these commands: yarn cache dir (yarn 1) and yarn config get cacheFolder (other versions)
• For npm the action uses this command: npm config get cache
• For pnpm the action uses this command: pnpm store path