A method that sets the props of the root component, and re-renders. Useful for when you are
wanting to test how the component behaves over time with changing props. Calling this, for
instance, will call the componentWillReceiveProps
lifecycle method.
Similar to setState
, this method accepts a props object and will merge it in with the already
existing props.
NOTE: can only be called on a wrapper instance that is also the root instance.
nextProps
(Object
): An object containing new props to merge in with the current props
ShallowWrapper
: Returns itself.
import PropTypes from 'prop-types';
function Foo({ name }) {
return (
<div className={name} />
);
}
Foo.propTypes = {
name: PropTypes.string.isRequired,
};
const wrapper = shallow(<Foo name="foo" />);
expect(wrapper.find('.foo')).to.have.length(1);
expect(wrapper.find('.bar')).to.have.length(0);
wrapper.setProps({ name: 'bar' });
expect(wrapper.find('.foo')).to.have.length(0);
expect(wrapper.find('.bar')).to.have.length(1);
import sinon from 'sinon';
const spy = sinon.spy(MyComponent.prototype, 'componentWillReceiveProps');
const wrapper = shallow(<MyComponent foo="bar" />);
expect(spy.calledOnce).to.equal(false);
wrapper.setProps({ foo: 'foo' });
expect(spy.calledOnce).to.equal(true);