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Multi step form or conditional rendering with DevTool console get an error Cannot update a component (`FormItemTest`) while rendering a different component (`FormItemTest`). To locate the bad setState() call inside `FormItemTest`

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#226 0 comments 3 reactions 0 assignees View on GitHub

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
42/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
react, typescript
Domain
devtools

Research direction

Start with the provided Demo reproduction using FormProvider, conditional Step2 rendering, getStep(step), and . Reproduce the warning with DevTool enabled, then inspect the DevTool component and its control subscription or rendering path. Done means the multi-step example no longer reports the setState-during-render warning while DevTool remains enabled.

Written by the indexing model from the issue text.

Description

The collection of fields in react hook form meets expectations. Confirmed to be a bug in DevTool. when I annotate DevTool,no more errors reported.

this is example code

import {
  useForm,
  FormProvider
} from 'react-hook-form';
import { zodResolver } from '@hookform/resolvers/zod';
import { DevTool } from '@hookform/devtools';

import FormItemTest from '~/components/form/FormItemTest';

import {
  useState
} from 'react';

import * as z from 'zod';

const schema = z.object({
  step1: z.string(),
  step2: z.string()
});

function Step1() {
  return (
    <FormItemTest name='step1' />
  )
}

function Step2() {
  return (
    <FormItemTest name='step2' />
  )
}

function getStep(step: number) {
  switch (step) {
    case 0:
      return <Step1 />;
    case 1:
      return <Step2 />;
    default:
      return null;
  }
}

export default function Demo() {
  const [show, setShow] = useState(false);
  const [step, setStep] = useState(0);

  const methods = useForm({
    resolver: zodResolver(schema),
    mode: 'onChange'
  });

  const onSubmit = methods.handleSubmit(values => {
    console.log(values);
  });

  return (
    <div>
      <FormProvider {...methods}>
        <form>
          <Step1 />
          {show && <Step2 />}
          {getStep(step)}
        </form>
      </FormProvider>
      <DevTool control={methods.control} />
      <button onClick={() => setShow(s => !s)}>Toggle Step2</button>
      <button onClick={onSubmit}>Submit</button>
      <button onClick={() => setStep(s => s + 1)}>Next Step</button>
    </div>
  )
}
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Dominant language
TypeScript
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Forks
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