Revert "Remove Danger CI"

This reverts commit ae4a770d6b.

.gitlab-ci.yml

@@ -22,6 +22,13 @@ deps:
     changes:
       - yarn.lock
 
+danger:
+  stage: test
+  script: npx danger ci
+  cache: []
+  only:
+    - merge_requests
+
 lint-js:
   stage: test
   script: yarn lint:js

dangerfile.ts

@@ -0,0 +1,13 @@
+import { danger, warn, message } from 'danger';
+
+const docs = danger.git.fileMatch('docs/**/*.md');
+const app = danger.git.fileMatch('app/**/*.(js|ts|tsx)');
+const tests = danger.git.fileMatch('*/__tests__/*');
+
+if (docs.edited) {
+  message('Thanks - We :heart: our [documentarians](http://www.writethedocs.org/)!');
+}
+
+if (app.modified && !tests.modified) {
+  warn('You have app changes without tests.');
+}

package.json

@@ -209,6 +209,7 @@
     "babel-eslint": "^10.1.0",
     "babel-jest": "^28.1.0",
     "cross-env": "^7.0.3",
+    "danger": "^11.0.7",
     "eslint": "^7.0.0",
     "eslint-plugin-import": "^2.25.4",
     "eslint-plugin-jsdoc": "^39.2.9",