metamask-extension/shared/modules/browser-runtime.utils.test.js

import sinon from 'sinon';
import browser from 'webextension-polyfill';
import log from 'loglevel';
import * as BrowserRuntimeUtil from './browser-runtime.utils';

const mockLastError = { message: 'error', stack: [] };

describe('Browser Runtime Utils', () => {
  beforeAll(() => {
    sinon.replace(browser, 'runtime', {
      lastError: undefined,
    });
  });

  describe('checkForLastError', () => {
    it('should return undefined if no lastError found', () => {
      expect(BrowserRuntimeUtil.checkForLastError()).toBeUndefined();
    });

    it('should return the lastError (Error object) if lastError is found', () => {
      sinon.stub(browser.runtime, 'lastError').value(mockLastError);

      expect(BrowserRuntimeUtil.checkForLastError()).toStrictEqual(
        mockLastError,
      );
    });

    it('should return an Error object if the lastError is found with no stack', () => {
      sinon
        .stub(browser.runtime, 'lastError')
        .value({ message: mockLastError.message });

      const result = BrowserRuntimeUtil.checkForLastError();

      expect(result).toStrictEqual(expect.any(Error));
      expect(result).toHaveProperty('stack');
      expect(result.message).toBe(mockLastError.message);
    });
  });

  describe('checkForLastErrorAndLog', () => {
    it('should log and return error if error was found', () => {
      sinon.stub(browser.runtime, 'lastError').value({ ...mockLastError });
      sinon.stub(log, 'error');

      const result = BrowserRuntimeUtil.checkForLastErrorAndLog();

      expect(log.error.calledWith(result)).toBeTruthy();
      expect(result).toStrictEqual(mockLastError);

      log.error.restore();
    });
  });
});