diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 42960d83..26e8b5c8 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -6,29 +6,35 @@ jobs:
   lint:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v2
-    - uses: actions/setup-node@v2
-      with:
-        node-version: '14'
-    - run: npm install
-    - run: grunt check
-      working-directory: ./scripts
+      - uses: actions/checkout@v2
+      - uses: actions/setup-node@v2
+        with:
+          node-version: "14"
+      - run: npm install
+      - run: grunt check
+        working-directory: ./scripts
+  build-matrix:
+    name: Build matrix for unit test
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - id: read-matrix
+        name: Read build matrix
+        run: echo "::set-output name=matrix::`jq -c . test/unit/config/run_matrix.json`"
+    outputs:
+      matrix: ${{ steps.read-matrix.outputs.matrix }}
   unit-test:
+    needs: build-matrix
     runs-on: ${{ matrix.os }}
     strategy:
-      matrix:
-        os: [ubuntu-latest, windows-latest, macos-latest]
-        browser: [ChromeWithFlags, FirefoxWithFlags]
-        include:
-          - os: windows-latest
-            browser: EdgeWithFlags
+      matrix: ${{ fromJSON(needs.build-matrix.outputs.matrix)[github.event_name] }}
     steps:
-    - uses: actions/checkout@v2
-    - uses: actions/setup-node@v2
-      with:
-        node-version: '14'
-    - run: npm install
-    - name: Run test cases
-      env:
-        BROWSER: ${{matrix.browser}}
-      run: npm run unittest
+      - uses: actions/checkout@v2
+      - uses: actions/setup-node@v2
+        with:
+          node-version: "14"
+      - run: npm install
+      - name: Run test cases
+        env:
+          BROWSER: ${{ matrix.browser }}
+        run: npm run unittest
diff --git a/package.json b/package.json
index d9b4cc4f..3884d46a 100644
--- a/package.json
+++ b/package.json
@@ -57,6 +57,6 @@
   },
   "scripts": {
     "postinstall": "cd scripts && grunt prepare",
-    "unittest": "node ./node_modules/karma/bin/karma start test/unit/karma/ci.config.js"
+    "unittest": "node ./node_modules/karma/bin/karma start test/unit/config/karma.config.js"
   }
 }
diff --git a/test/unit/karma/ci.config.js b/test/unit/config/karma.config.js
similarity index 100%
rename from test/unit/karma/ci.config.js
rename to test/unit/config/karma.config.js
diff --git a/test/unit/config/run_matrix.json b/test/unit/config/run_matrix.json
new file mode 100644
index 00000000..d28e14b3
--- /dev/null
+++ b/test/unit/config/run_matrix.json
@@ -0,0 +1,34 @@
+{
+  "push": {
+    "os": [
+      "ubuntu-latest",
+      "windows-latest",
+      "macos-latest"
+    ],
+    "browser": [
+      "ChromeWithFlags",
+      "FirefoxWithFlags"
+    ],
+    "include": [
+      {
+        "os": "windows-latest",
+        "browser": "EdgeWithFlags"
+      }
+    ]
+  },
+  "pull_request": {
+    "os": [
+      "ubuntu-latest"
+    ],
+    "browser": [
+      "ChromeWithFlags",
+      "FirefoxWithFlags"
+    ],
+    "include": [
+      {
+        "os": "windows-latest",
+        "browser": "EdgeWithFlags"
+      }
+    ]
+  }
+}
\ No newline at end of file