fix(profiling): Populate Hermes runtime version on JS profiles (#6817)

The Hermes JS profile payload has always sent an empty `runtime.version`
placeholder. Wire it up to the existing `getHermesVersion()` helper so
profiles carry the real Hermes version (falling back to `''` when Hermes
does not report one, matching the previous behavior).

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

Author: antonis

CHANGELOG.md

@@ -6,6 +6,12 @@
 > make sure you follow our [migration guide](https://docs.sentry.io/platforms/react-native/migration/) first.
 <!-- prettier-ignore-end -->
 
+## Unreleased
+
+### Fixes
+
+- Populate the Hermes runtime version on JS profiles instead of sending an empty value ([#6817](https://github.com/getsentry/sentry-react-native/pull/6817))
+
 ## 8.29.0
 
 ### Features

packages/core/src/js/profiling/utils.ts

@@ -12,7 +12,7 @@ import type {
   RawThreadCpuProfile,
 } from './types';
 
-import { getDefaultEnvironment } from '../utils/environment';
+import { getDefaultEnvironment, getHermesVersion } from '../utils/environment';
 import { getDebugMetadata } from './debugid';
 
 /**
@@ -95,7 +95,7 @@ export function enrichCombinedProfileWithEventContext(
     event_id: profile_id,
     runtime: {
       name: 'hermes',
-      version: '', // TODO: get hermes version
+      version: getHermesVersion() ?? '',
     },
     timestamp: profilingStartTimestampNs
       ? new Date(profilingStartTimestampNs / 1e6).toISOString()

packages/core/test/profiling/utils.test.ts

@@ -10,7 +10,7 @@ import {
   enrichAndroidProfileWithEventContext,
   enrichCombinedProfileWithEventContext,
 } from '../../src/js/profiling/utils';
-import { getDefaultEnvironment } from '../../src/js/utils/environment';
+import { getDefaultEnvironment, getHermesVersion } from '../../src/js/utils/environment';
 import { createMockMinimalValidAndroidProfile, createMockMinimalValidHermesProfileEvent } from './fixtures';
 
 describe('enrichCombinedProfileWithEventContext', () => {
@@ -19,6 +19,29 @@ describe('enrichCombinedProfileWithEventContext', () => {
     (getDebugMetadata as jest.Mock).mockReturnValue([]);
   });
 
+  test('should set the hermes runtime version from getHermesVersion', () => {
+    // OSS Hermes reports the version it was built against, e.g. `for RN 0.76.0`, not a semver.
+    (getHermesVersion as jest.Mock).mockReturnValue('for RN 0.76.0');
+    const profile: CombinedProfileEvent = createMockMinimalValidHermesProfileEvent();
+    const event = createMockEvent();
+
+    const result = enrichCombinedProfileWithEventContext('profile-id', profile, event);
+
+    expect(result).not.toBeNull();
+    expect(result!.runtime).toEqual({ name: 'hermes', version: 'for RN 0.76.0' });
+  });
+
+  test('should fall back to an empty runtime version when the hermes version is unavailable', () => {
+    (getHermesVersion as jest.Mock).mockReturnValue(undefined);
+    const profile: CombinedProfileEvent = createMockMinimalValidHermesProfileEvent();
+    const event = createMockEvent();
+
+    const result = enrichCombinedProfileWithEventContext('profile-id', profile, event);
+
+    expect(result).not.toBeNull();
+    expect(result!.runtime).toEqual({ name: 'hermes', version: '' });
+  });
+
   function createMockEvent(overrides?: Partial<Event>): Event {
     return {
       event_id: 'test-event-id',