fix(core): Mark stack trace from captureMessage with `attatchStackT…

…race: true` as synthetic (#14670)

Analogously to #14668 for browser, this patch marks synthetic exceptions
captured during a `captureException()` call as synthetic.

dev-packages/node-integration-tests/suites/public-api/captureMessage/simple_message_attachStackTrace/scenario.ts

@@ -0,0 +1,11 @@
+import { loggingTransport } from '@sentry-internal/node-integration-tests';
+import * as Sentry from '@sentry/node';
+
+Sentry.init({
+  dsn: 'https://public@dsn.ingest.sentry.io/1337',
+  release: '1.0',
+  transport: loggingTransport,
+  attachStacktrace: true,
+});
+
+Sentry.captureMessage('Message');

dev-packages/node-integration-tests/suites/public-api/captureMessage/simple_message_attachStackTrace/test.ts

@@ -0,0 +1,25 @@
+import { cleanupChildProcesses, createRunner } from '../../../../utils/runner';
+
+afterAll(() => {
+  cleanupChildProcesses();
+});
+
+test('capture a simple message string with a stack trace if `attachStackTrace` is `true`', done => {
+  createRunner(__dirname, 'scenario.ts')
+    .expect({
+      event: {
+        message: 'Message',
+        level: 'info',
+        exception: {
+          values: [
+            {
+              mechanism: { synthetic: true, type: 'generic', handled: true },
+              value: 'Message',
+              stacktrace: { frames: expect.any(Array) },
+            },
+          ],
+        },
+      },
+    })
+    .start(done);
+});

packages/core/src/utils-hoist/eventbuilder.ts

@@ -193,6 +193,7 @@ export function eventFromMessage(
           },
         ],
       };
+      addExceptionMechanism(event, { synthetic: true });
     }
   }
 

packages/core/test/utils-hoist/eventbuilder.test.ts

@@ -1,5 +1,5 @@
 import type { Client } from '../../src/types-hoist';
-import { eventFromUnknownInput } from '../../src/utils-hoist/eventbuilder';
+import { eventFromMessage, eventFromUnknownInput } from '../../src/utils-hoist/eventbuilder';
 import { nodeStackLineParser } from '../../src/utils-hoist/node-stack-trace';
 import { createStackParser } from '../../src/utils-hoist/stacktrace';
 
@@ -154,3 +154,63 @@ describe('eventFromUnknownInput', () => {
     expect(event.exception?.values?.[0]?.value).toBe('Object captured as exception with keys: foo, prop');
   });
 });
+
+describe('eventFromMessage', () => {
+  it('creates an event from a string message', () => {
+    const event = eventFromMessage(stackParser, 'Test Message');
+    expect(event).toEqual({
+      event_id: undefined, // this is undefined because the hint isn't passed
+      level: 'info',
+      message: 'Test Message',
+    });
+  });
+
+  it('attaches a synthetic exception if passed and `attachStackTrace` is true', () => {
+    const syntheticException = new Error('Test Message');
+    const event = eventFromMessage(
+      stackParser,
+      'Test Message',
+      'info',
+      { syntheticException, event_id: '123abc' },
+      true,
+    );
+
+    expect(event).toEqual({
+      event_id: '123abc',
+      exception: {
+        values: [
+          {
+            mechanism: {
+              handled: true,
+              synthetic: true,
+              type: 'generic',
+            },
+            stacktrace: {
+              frames: expect.any(Array),
+            },
+            value: 'Test Message',
+          },
+        ],
+      },
+      level: 'info',
+      message: 'Test Message',
+    });
+  });
+
+  it("doesn't attach a synthetic exception if `attachStackTrace` is false", () => {
+    const syntheticException = new Error('Test Message');
+    const event = eventFromMessage(
+      stackParser,
+      'Test Message',
+      'info',
+      { syntheticException, event_id: '123abc' },
+      false,
+    );
+
+    expect(event).toEqual({
+      event_id: '123abc',
+      level: 'info',
+      message: 'Test Message',
+    });
+  });
+});