From 4a7aa216004fff8d1e59d649e8cc56bb27852bec Mon Sep 17 00:00:00 2001
From: Charly Gomez <charly.gomez@sentry.io>
Date: Thu, 27 Feb 2025 18:09:16 +0100
Subject: [PATCH] feat(core): Default filter unactionable error (#15527)

We've been filtering a specific "undefined is not an object" error that
referenced "a.L" in our error filters. However, similar errors occured
with other uppercase letters (e.g. `a.K`) - they all represent the same
class of non-actionable error.

This pr just updates the filter to use a regex for this pattern.

ref https://github.com/getsentry/sentry/issues/85531
---
 .../core/src/integrations/eventFilters.ts     |  2 +-
 .../lib/integrations/eventFilters.test.ts     | 30 +++++++++++++++++++
 2 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/packages/core/src/integrations/eventFilters.ts b/packages/core/src/integrations/eventFilters.ts
index ab935ec01321..a3fd2f5fb19b 100644
--- a/packages/core/src/integrations/eventFilters.ts
+++ b/packages/core/src/integrations/eventFilters.ts
@@ -15,7 +15,7 @@ const DEFAULT_IGNORE_ERRORS = [
   /^ResizeObserver loop completed with undelivered notifications.$/, // The browser logs this when a ResizeObserver handler takes a bit longer. Usually this is not an actual issue though. It indicates slowness.
   /^Cannot redefine property: googletag$/, // This is thrown when google tag manager is used in combination with an ad blocker
   /^Can't find variable: gmo$/, // Error from Google Search App https://issuetracker.google.com/issues/396043331
-  "undefined is not an object (evaluating 'a.L')", // Random error that happens but not actionable or noticeable to end-users.
+  /^undefined is not an object \(evaluating 'a\.[A-Z]'\)$/, // Random error that happens but not actionable or noticeable to end-users.
   'can\'t redefine non-configurable property "solana"', // Probably a browser extension or custom browser (Brave) throwing this error
   "vv().getRestrictions is not a function. (In 'vv().getRestrictions(1,a)', 'vv().getRestrictions' is undefined)", // Error thrown by GTM, seemingly not affecting end-users
   "Can't find variable: _AutofillCallbackHandler", // Unactionable error in instagram webview https://developers.facebook.com/community/threads/320013549791141/
diff --git a/packages/core/test/lib/integrations/eventFilters.test.ts b/packages/core/test/lib/integrations/eventFilters.test.ts
index 07936f6ad444..51a15f909f5d 100644
--- a/packages/core/test/lib/integrations/eventFilters.test.ts
+++ b/packages/core/test/lib/integrations/eventFilters.test.ts
@@ -412,6 +412,14 @@ const TRANSACTION_EVENT_3: Event = {
   type: 'transaction',
 };
 
+function createUndefinedIsNotAnObjectEvent(evaluatingStr: string): Event {
+  return {
+    exception: {
+      values: [{ type: 'TypeError', value: `undefined is not an object (evaluating '${evaluatingStr}')` }],
+    },
+  };
+}
+
 describe.each([
   // eslint-disable-next-line deprecation/deprecation
   ['InboundFilters', inboundFiltersIntegration],
@@ -519,6 +527,28 @@ describe.each([
       expect(eventProcessor(FB_MOBILE_BROWSER_EVENT, {})).toBe(null);
     });
 
+    it("uses default filters (undefined is not an object (evaluating 'a.L'))", () => {
+      const eventProcessor = createEventFiltersEventProcessor(integrationFn);
+      expect(eventProcessor(createUndefinedIsNotAnObjectEvent('a.L'), {})).toBe(null);
+    });
+
+    it("uses default filters (undefined is not an object (evaluating 'a.K'))", () => {
+      const eventProcessor = createEventFiltersEventProcessor(integrationFn);
+      expect(eventProcessor(createUndefinedIsNotAnObjectEvent('a.K'), {})).toBe(null);
+    });
+
+    it("doesn't use default filters for (undefined is not an object (evaluating 'a.store'))", () => {
+      const eventProcessor = createEventFiltersEventProcessor(integrationFn);
+      const event = createUndefinedIsNotAnObjectEvent('a.store');
+      expect(eventProcessor(event, {})).toBe(event);
+    });
+
+    it("doesn't use default filters for (undefined is not an object (evaluating 'this._perf.domInteractive'))", () => {
+      const eventProcessor = createEventFiltersEventProcessor(integrationFn);
+      const event = createUndefinedIsNotAnObjectEvent('a.store');
+      expect(eventProcessor(event, {})).toBe(event);
+    });
+
     it('filters on last exception when multiple present', () => {
       const eventProcessor = createEventFiltersEventProcessor(integrationFn, {
         ignoreErrors: ['incorrect type given for parameter `chewToy`'],