fix(ci): installing dependencies from the cache

Author: Scrip7

.github/workflows/main.yml

@@ -1,26 +1,47 @@
 name: CI
-on: [push]
-jobs:
-  build:
-    name: Build, lint, and test on Node ${{ matrix.node }} and ${{ matrix.os }}
 
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+  # Allows to run this workflow manually from the Actions tab
+  workflow_dispatch:
+
+jobs:
+  ci:
+    name: CI on Node ${{ matrix.node }} and ${{ matrix.os }}
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        node: ['12.x', '14.x']
-        os: [ubuntu-latest, windows-latest, macOS-latest]
+        node-version: ['12.x', '14.x', '16.x']
+        os: [ubuntu-latest]
 
     steps:
       - name: Checkout repo
         uses: actions/checkout@v2
 
-      - name: Use Node ${{ matrix.node }}
-        uses: actions/setup-node@v1
+      - name: Install Node ${{ matrix.node-version }}
+        uses: actions/setup-node@v2
+        with:
+          node-version: ${{ matrix.node-version }}
+
+      # See: https://github.com/actions/cache/blob/main/examples.md#node---yarn
+      - name: Get Yarn cache directory
+        id: yarn-cache-dir-path
+        run: echo "::set-output name=dir::$(yarn cache dir)"
+
+      - name: Use Yarn cache
+        uses: actions/cache@v2
+        id: yarn-cache
         with:
-          node-version: ${{ matrix.node }}
+          path: ${{ steps.yarn-cache-dir-path.outputs.dir }}
+          key: ${{ matrix.os }}-yarn-${{ matrix.node-version }}-${{ hashFiles('**/yarn.lock') }}
 
-      - name: Install deps and build (with cache)
-        uses: bahmutov/npm-install@v1
+      - name: Install dependencies
+        # `--prefer-offline` gives local cache the priority to restore
+        run: yarn install --prefer-offline --frozen-lockfile
 
       - name: Lint
         run: yarn lint