ReactTestUtils - Find Element By Component, Class, Tag, Id

This is the child article of ReactTestUtils - Tutorial. In this article, I will explain how to find element with examples.

Examples - Source Code

Example

This is sample example.

import React from 'react';
import SubRoot from './sub-root'

class Root extends React.Component {
  constructor(props) {
    super(props);

    this.state = {
      name: ''
    };
  }

  render() {
    return (
      <div>
        <h1>Hello World!!</h1>

        <p>
          Please input your name here:
          <input className="myInput"
            onChange={this.handleChange}
            value={this.state.name}
          />
        </p>
        <SubRoot/>
        <p>Hello, {this.state.name} </p>
      </div>
    );
  }

  handleChange(e) {
    var newName = e.target.value();

    this.setState({
      name: newName
    });
  }
}

export default Root;

By Tag

scryRenderedDOMComponentsWithTag

Finds all DOM elements of components in the rendered tree that are DOM components with the tag name matching tagName.

findRenderedDOMComponentWithTag

Like scryRenderedDOMComponentsWithTag but expects there to be one result, and returns that one result, or throws exception if there is any other number of matches besides one.

it('find element with tag', function () {
    var root = TestUtils.renderIntoDocument(<Root/>);
    // scryRenderedDOMComponentsWithTag
    var spanElm = TestUtils.scryRenderedDOMComponentsWithTag(root, 'span');
    expect(spanElm.length).toEqual(0);
    var h1Elm = TestUtils.scryRenderedDOMComponentsWithTag(root, 'h1');
    expect(h1Elm.length).toEqual(1);
    // findRenderedDOMComponentWithTag
    var h1Elm = TestUtils.findRenderedDOMComponentWithTag(root, 'h1');
    expect(h1Elm).toExist();
});

By Class

scryRenderedDOMComponentsWithClass

Finds all DOM elements of components in the rendered tree that are DOM components with the class name matching className.

findRenderedDOMComponentWithClass

Like scryRenderedDOMComponentsWithClass() but expects there to be one result, and returns that one result, or throws exception if there is any other number of matches besides one.

it('find element with class', function () {
    var root = TestUtils.renderIntoDocument(<Root/>);
    // scryRenderedDOMComponentsWithClass
    var inputElmArr = TestUtils.scryRenderedDOMComponentsWithClass(root, 'myInput');
    expect(inputElmArr.length).toEqual(1);
    // findRenderedDOMComponentsWithClass
    var inputElm = TestUtils.findRenderedDOMComponentWithClass(root, 'myInput');
    expect(inputElm).toExist();
});

By Component

scryRenderedComponentsWithType

Finds all instances of components with type equal to componentClass.

findRenderedComponentWithType

Same as scryRenderedComponentsWithType() but expects there to be one result and returns that one result, or throws exception if there is any other number of matches besides one.

it('find element by Component', function () {

it('find element by Component', function () {
    var root = TestUtils.renderIntoDocument(<Root/>);
    // scryRenderedComponentsWithType
    var compArr = TestUtils.scryRenderedComponentsWithType(root, SubRoot);
    expect(compArr.length).toEqual(1);
    // findRenderedComponentsWithType
    var comp = TestUtils.findRenderedComponentWithType(root, SubRoot);
    expect(comp).toExist();
});

By Id

There is no function to get React element by Id. We can use findAllInRenderedTree to Component by Id.

function scryRenderedDOMComponentsWithId(tree, id) {
  return TestUtils.findAllInRenderedTree(tree, function(inst) {
    return TestUtils.isDOMComponent(inst) && inst.id === id;
  });
}

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