ref(core): Simplify linkedErrors mechanism logic

packages/core/src/utils/aggregate-errors.ts

@@ -99,10 +99,9 @@ function aggregateExceptionsFromError(
 }
 
 function applyExceptionGroupFieldsForParentException(exception: Exception, exceptionId: number): void {
-  // Don't know if this default makes sense. The protocol requires us to set these values so we pick *some* default.
-  exception.mechanism = exception.mechanism || { type: 'generic', handled: true };
-
   exception.mechanism = {
+    handled: true,
+    type: 'auto.core.linkedErrors',
     ...exception.mechanism,
     ...(exception.type === 'AggregateError' && { is_exception_group: true }),
     exception_id: exceptionId,
@@ -115,10 +114,8 @@ function applyExceptionGroupFieldsForChildException(
   exceptionId: number,
   parentId: number | undefined,
 ): void {
-  // Don't know if this default makes sense. The protocol requires us to set these values so we pick *some* default.
-  exception.mechanism = exception.mechanism || { type: 'generic', handled: true };
-
   exception.mechanism = {
+    handled: true,
     ...exception.mechanism,
     type: 'chained',
     source,

packages/core/test/lib/utils/aggregate-errors.test.ts

@@ -160,6 +160,26 @@ describe('applyAggregateErrorsToEvent()', () => {
     expect(event.exception?.values?.[event.exception.values.length - 1]?.mechanism?.type).toBe('instrument');
   });
 
+  test('should assign a defualt mechanism type for the root exception', () => {
+    const fakeAggregateError = new FakeAggregateError(
+      [new Error('Nested Error 1'), new Error('Nested Error 2')],
+      'Root Error',
+    );
+
+    const exceptionFromError = (_stackParser: StackParser, ex: Error): Exception => {
+      return { value: ex.message, type: ex.name };
+    };
+
+    const event: Event = { exception: { values: [exceptionFromError(stackParser, fakeAggregateError)] } };
+    const eventHint: EventHint = { originalException: fakeAggregateError };
+
+    applyAggregateErrorsToEvent(exceptionFromError, stackParser, 'cause', 100, event, eventHint);
+
+    expect(event.exception?.values?.[event.exception.values.length - 1]?.mechanism?.type).toBe(
+      'auto.core.linkedErrors',
+    );
+  });
+
   test('should recursively walk mixed errors (Aggregate errors and based on `key`)', () => {
     const chainedError: ExtendedError = new Error('Nested Error 3');
     chainedError.cause = new Error('Nested Error 4');