componentWillReceiveProps calls previous onChange if onChange prop was updated

[FunkMonkey]

Prerequisites

• I have read the documentation;
• In the case of a bug report, I understand that providing a SSCCE example is tremendously useful to the maintainers.
• Ideally, I'm providing a sample JSFiddle or a shared playground link demonstrating the issue.

Description

When a form is updated with new props which contain a new onChange callback, the previous onChange callback will be called instead, if the validated formData doesn't deep equal the new formData. This causes problems if onChange is a closure containing important data that changed inbetween.

Steps to Reproduce

1. Create a form with an onChange callback in the props
2. Update the form (same key) with a new onChange callback in the props

Reduced Example:

function SomeComponent(props) {
  const onChange = () {
    console.log(props.someValue);
  }
  return <Form onChange={onChange} />
}

Considering someValue is counting up like 1, 2 etc. then the calls to onChange will log 1, 1, 2, 3 etc.

Expected behavior

New onChange callback called.

Actual behavior

Previous onChange callback called.

The problem lies in Form.js#44:

  UNSAFE_componentWillReceiveProps(nextProps) {
    const nextState = this.getStateFromProps(nextProps, nextProps.formData);
    if (
      !deepEquals(nextState.formData, nextProps.formData) &&
      !deepEquals(nextState.formData, this.state.formData) &&
      this.props.onChange // should be nextProps.onChange
    ) {
      this.props.onChange(nextState); // should be nextProps.onChange
    }
    this.setState(nextState);
  }

Version

"react-jsonschema-form": "1.8.1"

[SivaGanesh56]

any update on this ?

[DanielHabenicht]

There is a PR that is not yet merged?

We have the same problem. Anything I could help with unblocking?

[heath-freenome]

Fixed in v5 beta via #3052, see the 5.x migration guide