fix(breadcrumbs): Crash when passing array as data to addBreadcrumb.

CHANGELOG.md

@@ -10,6 +10,8 @@
 
 - fix(ttid): End and measure TTID regardless current active span ([#4019](https://github.com/getsentry/sentry-react-native/pull/4019))
   - Fixes possible missing TTID measurements and spans
+- Fix crash when passing array as data to `Sentry.addBreadcrumb({ data: [] })` ([#4021](https://github.com/getsentry/sentry-react-native/pull/4021))
+  - The expected `data` type is plain JS object, otherwise the data might be lost.
 
 ### Dependencies
 

src/js/utils/normalize.ts

@@ -8,12 +8,17 @@ const KEY = 'value';
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
 export function convertToNormalizedObject(data: unknown): Record<string, any> {
   const normalized: unknown = normalize(data);
-  if (normalized === null || typeof normalized !== 'object') {
+  if (
+    normalized !== null &&
+    typeof normalized === 'object' &&
+    !Array.isArray(normalized) &&
+    normalized.constructor === Object
+  ) {
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    return normalized as Record<string, any>;
+  } else {
     return {
       [KEY]: normalized,
     };
-  } else {
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    return normalized as Record<string, any>;
   }
 }

test/utils/normalize.test.ts

@@ -21,5 +21,18 @@ describe('normalize', () => {
       const actualResult = convertToNormalizedObject(null);
       expect(actualResult).toEqual({ value: null });
     });
+
+    test('converts array to an object', () => {
+      const actualResult = convertToNormalizedObject([]);
+      expect(actualResult).toEqual({ value: [] });
+    });
+
+    test('converts custom class to an object', () => {
+      class TestClass {
+        test: string = 'foo';
+      }
+      const actualResult = convertToNormalizedObject(new TestClass());
+      expect(actualResult).toEqual({ test: 'foo' });
+    });
   });
 });