Set anonymous Sentry user so alerts report users affected (#2840)

* Set anonymous Sentry user so alerts report users affected

Sentry alerts showed "Users: 0" because no user context was ever
attached to events. On @sentry/browser v9, sendDefaultPii defaults to
false (no IP), and the extension never called Sentry.setUser, so every
event arrived with an empty user and could not be attributed.

Attach the existing persisted anonymous analytics id (the same one
Amplitude uses) via Sentry.setUser, gated on the existing data-sharing
consent. No PII or wallet address — just an opaque per-install id, so
Sentry and Amplitude user counts stay aligned. Mirrors freighter-mobile.

Also harden generateRandomUserId: Math.random() can yield values < 1e-6
(exponential notation) or exactly 0, where split(".")[1] is undefined;
fall back to "0" so we never hand Sentry/Amplitude an undefined id.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* Address review: clear Sentry user on opt-out, stub getUserId in jest mock

- Clear the per-install user id (Sentry.setUser(null)) before Sentry.close
  on data-sharing opt-out. Sentry.close may still report (anonymized) until
  the next refresh; without this those reports would keep the id attached.
- Add getUserId to the helpers/metrics jest mock in setupTests so rendering
  ErrorTracking under test doesn't call an undefined mock.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: piyalbasu

config/jest/setupTests.tsx

@@ -79,6 +79,7 @@ jest.mock("helpers/metrics", () => ({
   registerHandler: () => {},
   emitMetric: () => {},
   initAmplitude: () => {},
+  getUserId: () => "test-user-id",
   metricsMiddleware: jest.fn(
     () => () => (next: any) => (action: any) => next(action),
   ),

extension/src/helpers/metrics.ts

@@ -111,7 +111,10 @@ const AMPLITUDE_FLUSH_INTERVAL_MS = 500;
 
 /** Mirrors mobile's `generateRandomUserId` — a numeric decimal string. */
 const generateRandomUserId = (): string =>
-  Math.random().toString().split(".")[1];
+  // Math.random() can yield values < 1e-6 (exponential notation, e.g. "4e-7")
+  // or exactly 0 ("0"), where `split(".")[1]` is undefined. Fall back to "0"
+  // so we never persist or hand Sentry/Amplitude an undefined user id.
+  Math.random().toString().split(".")[1] ?? "0";
 
 /** Session-level cache, mirrors mobile's module-level `sessionUserId` fallback. */
 let sessionUserId: string | null = null;
@@ -122,7 +125,7 @@ let sessionUserId: string | null = null;
  * - Reads from localStorage under key `"metrics_user_id"`
  * - Falls back to a session-only ID if storage is unavailable
  */
-const getUserId = (): string => {
+export const getUserId = (): string => {
   try {
     const stored = localStorage.getItem(METRICS_USER_ID);
     if (stored) {

extension/src/popup/components/ErrorTracking/index.tsx

@@ -2,6 +2,7 @@ import { useSelector } from "react-redux";
 import * as Sentry from "@sentry/browser";
 
 import { SENTRY_KEY } from "constants/env";
+import { getUserId } from "helpers/metrics";
 import { settingsDataSharingSelector } from "popup/ducks/settings";
 import { scrubPathGkey } from "popup/helpers/formatters";
 import { INDEXER_URL } from "@shared/constants/mercury";
@@ -45,14 +46,25 @@ export const ErrorTracking = () => {
         return event;
       },
     });
+
+    // Attach a stable anonymous user ID so Sentry can report "users
+    // affected" counts. Reuses the same persisted random ID as Amplitude
+    // (helpers/metrics getUserId) so user counts stay aligned across the two.
+    // No PII / wallet address — just an opaque per-install identifier.
+    // Mirrors freighter-mobile's Sentry.setUser in src/components/App.tsx.
+    Sentry.setUser({ id: getUserId() });
   }
 
   if (!isDataSharingAllowed) {
-    /* 
-    Note: Sentry.close does not completely disable calls to Sentry. Sentry will still report, but with a completely anonymized payload. 
+    /*
+    Note: Sentry.close does not completely disable calls to Sentry. Sentry will still report, but with a completely anonymized payload.
     When you refresh/reopen the app after disabling tracking, it will not initialize Sentry, thus disabling *all* calls to Sentry
     */
 
+    // Clear the per-install user id before closing. Sentry.close may still
+    // report (anonymized) until the next refresh; without this, those reports
+    // would keep the user id attached and defeat the anonymization.
+    Sentry.setUser(null);
     Sentry.close(500);
   }