1 files changed, 28 insertions, 0 deletions
diff --git a/app/assets/javascripts/reports/codequality_report/workers/codequality_comparison_worker.js b/app/assets/javascripts/reports/codequality_report/workers/codequality_comparison_worker.js
new file mode 100644
index 00000000000..fc55602f95c
--- /dev/null
+++ b/app/assets/javascripts/reports/codequality_report/workers/codequality_comparison_worker.js
@@ -0,0 +1,28 @@
+import { differenceBy } from 'lodash';
+
+const KEY_TO_FILTER_BY = 'fingerprint';
+
+// eslint-disable-next-line no-restricted-globals
+self.addEventListener('message', e => {
+  const { data } = e;
+
+  if (data === undefined) {
+    return null;
+  }
+
+  const { headIssues, baseIssues } = data;
+
+  if (!headIssues || !baseIssues) {
+    // eslint-disable-next-line no-restricted-globals
+    return self.postMessage({});
+  }
+
+  // eslint-disable-next-line no-restricted-globals
+  self.postMessage({
+    newIssues: differenceBy(headIssues, baseIssues, KEY_TO_FILTER_BY),
+    resolvedIssues: differenceBy(baseIssues, headIssues, KEY_TO_FILTER_BY),
+  });
+
+  // eslint-disable-next-line no-restricted-globals
+  return self.close();
+});