ci: Execute stryker:dry-run on branches (#302)

Dry run works by passing a glob that matches no file.
Additionally we reduce the reporters since there is nothing to report anyways.

We decided to go for a CLI approach instead of a separate config file,
since there is no way to extend config files, and we would like to avoid
any need to keep the two files in sync.

stryker-mutator/stryker-js#3088

Co-authored-by: Christian Bewernitz <coder@karfau.de>
Co-authored-by: Christopher J. Brody <chris.brody+brodybits@gmail.com>

.github/workflows/stryker.yml

@@ -6,6 +6,8 @@ name: run Stryker - Node.js CI
 on:
   push:
     branches: [ master ]
+  pull_request:
+    branches: [ master ]
 
 jobs:
   build:
@@ -23,6 +25,13 @@ jobs:
       with:
         node-version: ${{ matrix.node-version }}
     - run: npm ci
-    - run: npm run stryker
+
+    - if: ${{ github.event_name == 'pull_request' }}
+      # on pr branches we only do a dry-run that doesn't mutate anything but checks the configuration works
+      run: npm run stryker:dry-run
+
+    - if: ${{ github.event_name == 'push' }}
+      # on the default branch we run the full suite wich takes > 1 hour to run
+      run: npm run stryker
       env:
         STRYKER_DASHBOARD_API_KEY: ${{ secrets.STRYKER_DASHBOARD_API_KEY }}

package.json

@@ -30,6 +30,7 @@
     "lint": "eslint lib test",
     "start": "nodemon --watch package.json --watch lib --watch test --exec 'npm --silent run test && npm --silent run lint'",
     "stryker": "stryker run",
+    "stryker:dry-run": "stryker run -m '' --reporters progress",
     "test": "jest"
   },
   "engines": {