Fix RecurringError::toString

Summary: RecurringError::toString wasn't including the message. Fixed.

Reviewed By: passy

Differential Revision: D13732258

fbshipit-source-id: 71f5edef19de4e59d1c6c5bd549822871e36ede4

src/utils/__tests__/errors.node.js

@@ -0,0 +1,16 @@
+/**
+ * Copyright 2018-present Facebook.
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ * @format
+ */
+
+import {RecurringError} from '../errors';
+
+test('Check RecurringError toString output', () => {
+  const error = new RecurringError('something');
+  expect(error.toString()).toBe('[RecurringError] something');
+  /* $FlowFixMe intentionally coercing it to a string to make sure the correct
+   method is overridden */
+  expect('' + error).toBe('[RecurringError] something');
+});

src/utils/errors.js

@@ -11,4 +11,7 @@ export class RecurringError extends Error {
     super(message);
     this.name = 'RecurringError';
   }
+  toString(): string {
+    return `[${this.name}] ${this.message}`;
+  }
 }