TypeError: Cannot read property 'firstChild' of undefined when using import (ES6 via Babel)

[sebastiandeutsch]

I want to move my code from require to the official ES6 import syntax:

'use strict';

jest.dontMock('../../../timer/trackings/date-view');

import React from 'react/addons';

describe('DateView', function() {
  it('should show the actuall day', function() {
    var TestUtils = React.addons.TestUtils;
    var DateView = require('../../../timer/trackings/date-view');
    var dateMock = {
      calendar: function() {
        return "Today";
      }
    };
    var dateview = TestUtils.renderIntoDocument(<DateView date={dateMock}/>);

    expect(dateview.getDOMNode().textContent).toBe('Today');
  });
});

Unfortunately this gives me this error:

Using Jest CLI v0.2.2
 FAIL  app/assets/javascripts/jsx/__tests__/timer/trackings/date-view-test.jsx (0.711s)
● DateView › it should show the actuall day
  - TypeError: Cannot read property 'firstChild' of undefined
        at Object.ReactMount.findComponentRoot (/Users/sebastiandeutsch/development/ruby/timetracker/node_modules/react/lib/ReactMount.js:730:39)
        at Object.ReactMount.findReactNodeByID (/Users/sebastiandeutsch/development/ruby/timetracker/node_modules/react/lib/ReactMount.js:676:23)
        at Object.getNodeFromInstance (/Users/sebastiandeutsch/development/ruby/timetracker/node_modules/react/lib/ReactMount.js:165:32)
        at findDOMNode (/Users/sebastiandeutsch/development/ruby/timetracker/node_modules/react/lib/findDOMNode.js:52:23)
        at ReactBrowserComponentMixin.getDOMNode (/Users/sebastiandeutsch/development/ruby/timetracker/node_modules/react/lib/ReactBrowserComponentMixin.js:25:12)
        at Spec.<anonymous> (/Users/sebastiandeutsch/development/ruby/timetracker/app/assets/javascripts/jsx/__tests__/timer/trackings/date-view-test.jsx:20:21)
        at jasmine.Block.execute (/Users/sebastiandeutsch/development/ruby/timetracker/node_modules/jest-cli/vendor/jasmine/jasmine-1.3.0.js:1065:17)
        at jasmine.Queue.next_ (/Users/sebastiandeutsch/development/ruby/timetracker/node_modules/jest-cli/vendor/jasmine/jasmine-1.3.0.js:2098:31)
        at null._onTimeout (/Users/sebastiandeutsch/development/ruby/timetracker/node_modules/jest-cli/vendor/jasmine/jasmine-1.3.0.js:2088:18)
        at Timer.listOnTimeout [as ontimeout] (timers.js:112:15)
1 test failed, 0 tests passed (1 total)
Run time: 0.864s
npm ERR! Test failed.  See above for more details.
npm ERR! not ok code 0

when I'm writing the test case oldschool style:

'use strict';

jest.dontMock('../../../timer/trackings/date-view');

describe('DateView', function() {
  it('should show the actuall day', function() {
    var React = require('react/addons');
    var TestUtils = React.addons.TestUtils;
    var DateView = require('../../../timer/trackings/date-view');
    var dateMock = {
      calendar: function() {
        return "Today";
      }
    };
    var dateview = TestUtils.renderIntoDocument(<DateView date={dateMock}/>);

    expect(dateview.getDOMNode().textContent).toBe('Today');
  });
});

it passes. I assume it's the same issue like #186 but if I move the import inside the it(...) or a beforeEach I'll get a compile error:

'import' and 'export' may only appear at the top level (8:4)

Does anyone have a workaround or a solution to this problem?

[nifgraup]

It could be unrelated but I get the same error when adding new tests. The problem was introduced in this React commit: facebook/react@a194e51

It acts like we are hitting some kind of limit. Any added test causes the "Cannot read property 'firstChild' of undefined" error and it doesn't have to test react components.

Using karma+jasmine (not jest), babel, browserify. No ES6 modules.

[tom76kimo]

I bumped into this issue too yet without using ES6 or babel. The container from containersByReactRootID[reactRootID] is undefined in file ReactMount.js. And the function registerContainer seems not be called.

[nifgraup]

@tom76kimo can you test if this problem was introduced with facebook/react@a194e51 ?

[nifgraup]

Fixed by going to jasmine 1.3 from 2.2.

[sebastiandeutsch]

@nifgraup did you downgrade jasmine from 2.2 to 1.3?

[nifgraup]

Yes, that did the trick for some reason.

[nifgraup]

Back to Jasmine 2.x. Things seem to behave better when I unmount components after each test.

[cpojer]

Fixed in #741 for 0.9.0.

[github-actions]

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