fix(node-core): rejection warning in strict mode

Only print it if the reason doesn't have a stack. This matches the
behavior of Node.js.

Author: mohd-akram

dev-packages/node-core-integration-tests/suites/public-api/onUnhandledRejectionIntegration/mode-strict-error.js

@@ -0,0 +1,14 @@
+const Sentry = require('@sentry/node-core');
+const { setupOtel } = require('../../../utils/setupOtel.js');
+const { expectProcessToExit } = require('../../../utils/expect-process-to-exit');
+
+const client = Sentry.init({
+  dsn: 'https://public@dsn.ingest.sentry.io/1337',
+  integrations: [Sentry.onUnhandledRejectionIntegration({ mode: 'strict' })],
+});
+
+setupOtel(client);
+
+expectProcessToExit();
+
+Promise.reject(new Error('test rejection'));

dev-packages/node-core-integration-tests/suites/public-api/onUnhandledRejectionIntegration/test.ts

@@ -58,6 +58,22 @@ test rejection`);
       });
     }));
 
+  test('should not show warning for error-type promise rejections in strict mode', () =>
+    new Promise<void>(done => {
+      expect.assertions(5);
+
+      const testScriptPath = path.resolve(__dirname, 'mode-strict-error.js');
+
+      childProcess.execFile('node', [testScriptPath], { encoding: 'utf8' }, (err, stdout, stderr) => {
+        expect(err).not.toBeNull();
+        expect(err?.code).toBe(1);
+        expect(stdout).not.toBe("I'm alive!");
+        expect(stderr).toContain('Error: test rejection');
+        expect(stderr).not.toContain('The promise rejected with the reason');
+        done();
+      });
+    }));
+
   test('should not close process or warn on unhandled rejection in none mode', () =>
     new Promise<void>(done => {
       expect.assertions(3);

dev-packages/node-integration-tests/suites/public-api/onUnhandledRejectionIntegration/mode-strict-error.js

@@ -0,0 +1,11 @@
+const Sentry = require('@sentry/node');
+const { expectProcessToExit } = require('../../../utils/expect-process-to-exit');
+
+Sentry.init({
+  dsn: 'https://public@dsn.ingest.sentry.io/1337',
+  integrations: [Sentry.onUnhandledRejectionIntegration({ mode: 'strict' })],
+});
+
+expectProcessToExit();
+
+Promise.reject(new Error('test rejection'));

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

@@ -59,6 +59,22 @@ test rejection`);
       });
     }));
 
+  test('should not show warning for error-type promise rejections in strict mode', () =>
+    new Promise<void>(done => {
+      expect.assertions(5);
+
+      const testScriptPath = path.resolve(__dirname, 'mode-strict-error.js');
+
+      childProcess.execFile('node', [testScriptPath], { encoding: 'utf8' }, (err, stdout, stderr) => {
+        expect(err).not.toBeNull();
+        expect(err?.code).toBe(1);
+        expect(stdout).not.toBe("I'm alive!");
+        expect(stderr).toContain('Error: test rejection');
+        expect(stderr).not.toContain('The promise rejected with the reason');
+        done();
+      });
+    }));
+
   test('should not close process or warn on unhandled rejection in none mode', () =>
     new Promise<void>(done => {
       expect.assertions(3);

packages/node-core/src/integrations/onunhandledrejection.ts

@@ -143,9 +143,11 @@ function handleRejection(reason: unknown, mode: UnhandledRejectionMode): void {
       console.error(reason && typeof reason === 'object' && 'stack' in reason ? reason.stack : reason);
     });
   } else if (mode === 'strict') {
-    consoleSandbox(() => {
-      console.warn(rejectionWarning);
-    });
+    if (!(reason && typeof reason === 'object' && 'stack' in reason)) {
+      consoleSandbox(() => {
+        console.warn(rejectionWarning);
+      });
+    }
     logAndExitProcess(reason);
   }
   /* eslint-enable no-console */