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Testing React form components

In my tutorial-like application I have a AddForm component:

var React = require('react');
var Input = require('react-bootstrap').Input;
var TeamActions = require('../actions/team_actions.js');

var AddForm = React.createClass({
  handleFormSubmit: function(e) {
    e.preventDefault();

    var name = this._trimmedValue(this.refs.name);
    var rating = this._trimmedValue(this.refs.rating);

    if (name && rating) {
      TeamActions.addTeam(
        {name: name, rating: rating}
      );
      this._clearField(this.refs.name);
      this._clearField(this.refs.rating);
    }
  },

  _trimmedValue: function(field) {
    return field.getInputDOMNode().value.trim();
  },

  _clearField: function(field) {
    field.getInputDOMNode().value = '';
  },

  render: function() {
    return (
        <form onSubmit={this.handleFormSubmit}>
          <Input label="Name" type="text" placeholder="Name" ref="name" />
          <Input label="Rating" type="text" placeholder="Rating" ref="rating" />
          <Input bsStyle="primary" type="submit" value="Add!" />
        </form>
    );
  }
})

module.exports = AddForm;

TeamActions:

var McFly = require('mcfly');
var Flux = new McFly();
var TeamConstants = require('../constants/team_constants.js');


var TeamActions = Flux.createActions({
  addTeam: function(team) {
    return {
      actionType: TeamConstants.ADD_TEAM,
      team: team
    }
  }
});

module.exports = TeamActions;

As you can see, I'm using McFly and React-Bootstrap here.

Now I want to test it, using jest.

I would like to have following test cases:

1) if someone tries to submit a form with empty inputs, nothing should happen (to be more specific - there should be no interaction on TeamActions mock)

2) if one submits a form with valid name and rating, then there should be a proper call to TeamActions mock

3) if one submits a form with valid name and rating, then name and rating inputs should be cleaned.

How do I test it? Should I access the DOM somehow, using react's TestUtils?

Should I somehow simulate form submission? If so, how do I do that?

And last thing - my AddForm depends on TeamActions. By writing:

jest.dontMock('../add_form.js');

is jest instructed to mock all those dependencies (react, react-bootstrap, team_actions) or should I somehow mock TeamActions myself?

// edit:

Because someone said I asked too much quuestions in one topic, to be more specific:

How can I simulate a form submission with specific payload, using TestUtils? Do I need to mock TeamActions myself or is is mocked for me automatically?

like image 382
slnowak Avatar asked Feb 22 '15 15:02

slnowak


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1 Answers

React TestUtils allows you to simulate form submission:

var addForm = TestUtils.renderIntoDocument(AddForm(null));
var form = TestUtils.findRenderedDOMComponentWithTag(addForm, 'form');
TestUtils.Simulate.submit(form);

The way I would test the actions is by manually mocking out addTeam. Before simulating anything in the test, do something like:

var TeamActions = require('../actions/team_actions');
TeamActions.addTeam = jest.genMockFn();
/* then simulate submission... */
expect(TeamActions.addTeam).toBeCalledWith({name: 'name', rating: 'rating'});

For testing the input values, just use the refs.

addForm.refs.name.getDOMNode().value = 'Some Name';
/* perform some action that should clear input */
expect(addForm.refs.name.getDOMNode().value).toEqual('');

edit

To answer your edited question, it looks like you actually don't need to manually mock addTeam; I just tried it out and it seems like Jest figured out how to mock the McFly actions.

like image 138
Nathan Harper Avatar answered Sep 18 '22 20:09

Nathan Harper