import React, { useState } from 'react'; import { act, fireEvent, render, renderHook, screen, waitFor, } from '@testing-library/react'; import { Controller } from '../controller'; import type { Control, FieldValues, SubmitHandler, UseFormRegister, UseFormReturn, } from '../types'; import { useFieldArray } from '../useFieldArray'; import { useForm } from '../useForm'; import { FormProvider } from '../useFormContext'; import { useFormState } from '../useFormState'; import noop from '../utils/noop'; let i = 0; jest.mock('../logic/generateId', () => () => String(i++)); describe('useFieldArray', () => { beforeEach(() => { i = 0; }); describe('initialize', () => { it('should return default fields value', () => { const { result } = renderHook(() => { const { control } = useForm(); return useFieldArray({ control, name: 'test', }); }); expect(result.current.fields).toEqual([]); }); it('should populate default values into fields', () => { const { result } = renderHook(() => { const { control } = useForm({ defaultValues: { test: [{ test: '1' }, { test: '2' }] }, }); return useFieldArray({ control, name: 'test', }); }); expect(result.current.fields).toEqual([ { test: '1', id: '0' }, { test: '2', id: '1' }, ]); }); it('should populate values into fields instead of defaultValues', () => { const { result } = renderHook(() => { const { control } = useForm({ defaultValues: { test: [{ test: '3' }, { test: '21' }] }, values: { test: [{ test: '1' }, { test: '3' }, { test: '55' }] }, }); return useFieldArray({ control, name: 'test', }); }); expect(result.current.fields).toEqual([ { test: '1', id: '2' }, { test: '3', id: '3' }, { test: '55', id: '4' }, ]); }); it('should render with FormProvider', () => { const Provider = ({ children }: { children: React.ReactNode }) => { const methods = useForm(); return {children}; }; expect(() => renderHook(() => useFieldArray({ name: 'test' }), { wrapper: Provider, }), ).not.toThrow(); }); }); describe('with should unregister false', () => { it('should still remain input value with toggle', () => { const Component = () => { const { register, control } = useForm<{ test: { value: string; }[]; }>(); const [show, setShow] = React.useState(true); const { fields, append } = useFieldArray({ control, name: 'test', }); return (
{show && fields.map((field, i) => ( ))}
); }; render(); fireEvent.click(screen.getByRole('button', { name: 'append' })); expect(screen.getAllByRole('textbox').length).toEqual(1); fireEvent.click(screen.getByRole('button', { name: 'toggle' })); expect(screen.queryByRole('textbox')).not.toBeInTheDocument(); fireEvent.click(screen.getByRole('button', { name: 'toggle' })); expect(screen.getAllByRole('textbox').length).toEqual(1); }); it('should show errors during mount when mode is set to onChange', async () => { const Component = () => { const { register, control, formState: { isValid, errors }, } = useForm<{ test: { value: string }[] }>({ defaultValues: { test: [{ value: 'test' }], }, resolver: async () => ({ values: {}, errors: { test: [{ value: { message: 'wrong', type: 'test' } }], }, }), mode: 'onChange', }); const { fields, append } = useFieldArray({ name: 'test', control }); return (
{fields.map((field, i) => ( ))} {!isValid &&

not valid

} {errors.test &&

errors

}
); }; render(); expect(await screen.findByRole('textbox')).toBeVisible(); expect(await screen.findByText('not valid')).toBeVisible(); }); it('should retain input values during unmount', async () => { type FormValues = { test: { name: string }[]; }; const FieldArray = ({ control, register, }: { control: Control; register: UseFormRegister; }) => { const { fields } = useFieldArray({ control, name: 'test', }); return (
{fields.map((item, index) => { return (
); })}
); }; const App = () => { const [show, setShow] = React.useState(true); const { control, register } = useForm({ shouldUnregister: false, defaultValues: { test: [{ name: 'test' }], }, }); return (
{show && }
); }; render(); fireEvent.change(screen.getByRole('textbox'), { target: { value: '12345' }, }); fireEvent.click(screen.getByRole('button')); fireEvent.click(screen.getByRole('button')); expect((screen.getByRole('textbox') as HTMLInputElement).value).toEqual( '12345', ); }); }); describe('with resolver', () => { it('should provide updated form value each action', async () => { let formData = {}; const Component = () => { const { register, control, formState: { isValid }, } = useForm<{ data: string; test: { value: string }[]; }>({ resolver: (data) => { formData = data; return { values: {}, errors: {}, }; }, }); const { fields, append } = useFieldArray({ name: 'test', control }); return (
{fields.map((field, i) => ( ))} {isValid && 'valid'}
); }; render(); expect(await screen.findByText('valid')).toBeVisible(); fireEvent.click(screen.getByRole('button')); expect(formData).toEqual({ data: 'test', test: [{ value: '' }], }); }); it('should provide correct form data with nested field array', async () => { type FormValues = { test: { value: string; nestedArray: { value: string; }[]; }[]; }; let formData: any = {}; const Nested = ({ index, control, }: { control: Control; index: number; }) => { const { fields, append } = useFieldArray({ name: `test.${index}.nestedArray` as const, control, }); return (
{fields.map((item, i) => ( ))}
); }; const Component = () => { const { register, control, formState: { isValid }, } = useForm({ resolver: (data) => { formData = data; return { values: data, errors: {}, }; }, mode: 'onChange', defaultValues: { test: [{ value: '1', nestedArray: [{ value: '2' }] }], }, }); const { fields, remove } = useFieldArray({ name: 'test', control, }); return (
{fields.map((item, i) => (
))} {isValid && 'valid'}
); }; render(); fireEvent.click(screen.getByRole('button', { name: 'Append Nest' })); expect(await screen.findByText('valid')).toBeVisible(); expect(formData).toEqual({ test: [ { value: '1', nestedArray: [{ value: '2' }, { value: 'test' }], }, ], }); fireEvent.click(screen.getByRole('button', { name: 'delete' })); expect(formData).toEqual({ test: [], }); }); it('should report field array error during user action', async () => { const App = () => { const { register, control, formState: { errors }, } = useForm<{ test: { value: string }[]; }>({ mode: 'onChange', resolver: (data) => { return { values: data, errors: { test: { type: 'test', message: 'minLength', }, }, }; }, defaultValues: { test: [{ value: '1' }], }, }); const { fields, remove } = useFieldArray({ name: 'test', control, }); return (
{errors.test &&

minLength

} {fields.map((item, i) => (
))}
); }; render(); expect(screen.queryByText('minLength')).not.toBeInTheDocument(); fireEvent.click(screen.getByRole('button')); expect(await screen.findByText('minLength')).toBeVisible(); }); it('should not return schema error without user action', () => { const App = () => { const { register, control, formState: { errors }, } = useForm<{ test: { value: string }[]; }>({ mode: 'onChange', resolver: (data) => { return { values: data, errors: { test: { type: 'test', message: 'minLength', }, }, }; }, defaultValues: { test: [], }, }); const { fields } = useFieldArray({ name: 'test', control, }); return (
{errors.test &&

minLength

} {fields.map((item, i) => (
))}
); }; render(); expect(screen.queryByText('minLength')).not.toBeInTheDocument(); }); it('should update error when user action corrects it', async () => { const App = () => { const { register, control, formState: { errors }, } = useForm<{ test: { value: string }[]; }>({ mode: 'onChange', resolver: (data) => { if (data.test.length > 1) { return { values: data, errors: {}, }; } else { return { values: data, errors: { test: { type: 'test', message: 'minLength', }, }, }; } }, defaultValues: { test: [], }, }); const { fields, append } = useFieldArray({ name: 'test', control, }); return (
{errors.test &&

minLength

} {fields.map((item, i) => ( ))}
); }; render(); fireEvent.click(screen.getByRole('button')); await waitFor(() => expect(screen.queryByText('minLength')).toBeInTheDocument(), ); fireEvent.click(screen.getByRole('button')); await waitFor(() => expect(screen.queryByText('minLength')).not.toBeInTheDocument(), ); }); it('should update error when array is changed', async () => { const App = () => { const { register, control, formState: { errors }, } = useForm<{ test: { value: string }[]; }>({ mode: 'onChange', resolver: (data) => { const errors: { test?: any } = {}; if (data.test.length > 4) { errors.test = { type: 'toobig', message: 'WAY too many items' }; } else if (data.test.length > 3) { errors.test = { type: 'toobig', message: 'Too many items' }; } for (const [index, item] of data.test.entries()) { if (item.value === '') { errors.test = errors.test || []; errors.test[index] = { value: { type: 'required', message: 'Required' }, }; } } return { values: data, errors, }; }, defaultValues: { test: [{ value: '0' }, { value: '1' }, { value: '2' }], }, }); const { fields, append, remove } = useFieldArray({ name: 'test', control, }); return (
{errors.test?.type &&

Array error: {errors.test.message}

} {fields.map((item, i) => (
{errors.test?.[i]?.value && ( Item {i} error: {errors.test?.[i]?.value?.message} )}
))}
); }; render(); await waitFor(() => expect(screen.queryByText('Array error:')).not.toBeInTheDocument(), ); fireEvent.click(screen.getByRole('button', { name: 'append' })); await waitFor(() => expect( screen.queryByText('Array error: Too many items'), ).toBeInTheDocument(), ); fireEvent.click(screen.getByRole('button', { name: 'append' })); await waitFor(() => expect( screen.queryByText('Array error: WAY too many items'), ).toBeInTheDocument(), ); fireEvent.click(screen.getAllByRole('button', { name: 'remove' })[0]); await waitFor(() => expect( screen.queryByText('Array error: Too many items'), ).toBeInTheDocument(), ); fireEvent.click(screen.getAllByRole('button', { name: 'remove' })[0]); await waitFor(() => expect(screen.queryByText('Array error:')).not.toBeInTheDocument(), ); fireEvent.change(screen.getAllByRole('textbox')[0], { target: { value: '' }, }); await waitFor(() => expect( screen.queryByText('Item 0 error: Required'), ).toBeInTheDocument(), ); fireEvent.click(screen.getByRole('button', { name: 'append' })); await waitFor(() => { expect( screen.queryByText('Array error: Too many items'), ).toBeInTheDocument(); expect( screen.queryByText('Item 0 error: Required'), ).toBeInTheDocument(); }); fireEvent.click(screen.getByRole('button', { name: 'append' })); await waitFor(() => { expect( screen.queryByText('Array error: WAY too many items'), ).toBeInTheDocument(); expect( screen.queryByText('Item 0 error: Required'), ).toBeInTheDocument(); }); fireEvent.click(screen.getAllByRole('button', { name: 'remove' })[4]); await waitFor(() => { expect( screen.queryByText('Array error: Too many items'), ).toBeInTheDocument(); expect( screen.queryByText('Item 0 error: Required'), ).toBeInTheDocument(); }); fireEvent.click(screen.getAllByRole('button', { name: 'remove' })[3]); await waitFor(() => { expect( screen.queryByText('Array error: Too many items'), ).not.toBeInTheDocument(); expect( screen.queryByText('Item 0 error: Required'), ).toBeInTheDocument(); }); }); }); describe('when component unMount', () => { it('should keep field array values', async () => { let getValues: any; const Component = () => { const [show, setShow] = React.useState(true); const { register, control, getValues: tempGetValues } = useForm(); const { fields, append } = useFieldArray({ name: 'test', control }); getValues = tempGetValues; return ( <> {show && (
{fields.map((_, i) => ( ))}
)} ); }; render(); const button = screen.getByRole('button', { name: /append/i }); fireEvent.click(button); fireEvent.click(button); fireEvent.click(button); fireEvent.click(screen.getByRole('button', { name: 'setShow' })); expect(getValues()).toEqual({ test: [{ value: '' }, { value: '' }, { value: '' }], }); fireEvent.click(screen.getByRole('button', { name: 'setShow' })); expect(screen.getAllByRole('textbox').length).toEqual(3); }); it('should remove reset method when field array is removed', () => { let controlTemp: any; let fieldsTemp: unknown[] = []; const App = () => { const { register, control } = useForm({ defaultValues: { test: [{ value: 'default' }], }, }); const { fields, append } = useFieldArray({ name: 'test', control, }); controlTemp = control; fieldsTemp = fields; return (
{fields.map((field) => { return ; })}
); }; const { unmount } = render(); expect(fieldsTemp).toEqual([{ id: '0', value: 'default' }]); fireEvent.click(screen.getByRole('button')); expect(fieldsTemp).toEqual([ { id: '0', value: 'default' }, { id: '2', value: 'test', }, ]); unmount(); expect(controlTemp._names.array).toEqual(new Set(['test'])); expect(fieldsTemp).toEqual([ { id: '0', value: 'default' }, { id: '2', value: 'test', }, ]); }); it('should unset field array values correctly on DOM removing', async () => { interface NestedComponentProps extends Pick, 'control' | 'register'> { childIndex: number; } type FormValues = { test: { title: string; nested: { name: string; }[]; }[]; title: string; }; const NestedComponent = ({ childIndex, control, register, }: NestedComponentProps) => { const { fields } = useFieldArray({ control, name: `test.${childIndex}.nested` as `test.0.nested`, }); return (
{fields.map((field, index) => { return (
); })}
); }; const Component = () => { const { control, register } = useForm(); const { fields, append, remove } = useFieldArray({ control, name: 'test', }); return (
{fields.map((field, index) => { return (
); })}
); }; render(); const addChild = () => fireEvent.click(screen.getByText('Add child')); addChild(); expect(screen.getByText('Remove child')).toBeInTheDocument(); fireEvent.click(screen.getByText('Remove child')); expect(screen.queryByText('Remove child')).not.toBeInTheDocument(); addChild(); expect(screen.getByText('Remove child')).toBeInTheDocument(); }); }); describe('with should unregister true', () => { it('should not unregister field if unregister method is triggered', () => { let getValues: any; const Component = () => { const { register, unregister, control, getValues: tempGetValues, } = useForm(); const { fields, append } = useFieldArray({ name: 'test', control }); getValues = tempGetValues; React.useEffect(() => { if (fields.length >= 3) { unregister('test'); } }, [fields, unregister]); return (
{fields.map((field, i) => ( ))}
); }; render(); const button = screen.getByRole('button', { name: /append/i }); fireEvent.click(button); fireEvent.click(button); fireEvent.click(button); expect(getValues()).toEqual({ test: [{ value: '' }, { value: '' }, { value: '' }], }); }); it('should remove field array after useFieldArray is unmounted', () => { type FormValues = { test: { name: string }[]; }; const FieldArray = ({ control }: { control: Control }) => { const { fields } = useFieldArray({ control, name: 'test', }); return (
{fields.map((item, index) => { return ( ); })}
); }; const App = () => { const [show, setShow] = React.useState(true); const { control } = useForm({ shouldUnregister: true, defaultValues: { test: [{ name: 'test' }], }, }); return (
{show && }
); }; render(); expect(screen.getByRole('textbox')).toBeVisible(); fireEvent.click(screen.getByRole('button')); expect(screen.queryByRole('textbox')).not.toBeInTheDocument(); }); }); describe('setError', () => { it('should be able to set an field array error', async () => { const Component = () => { const { register, setError, control, formState: { errors }, } = useForm(); const { fields, append, remove } = useFieldArray({ name: 'test', control, }); React.useEffect(() => { if (fields.length === 0) { setError('test', { type: 'min length', }); } }, [fields, setError]); return (
{fields.map((_, i) => (
))}

{errors.test && 'Error'}

); }; render(); fireEvent.click(screen.getByRole('button', { name: 'append' })); fireEvent.click(screen.getByRole('button', { name: 'submit' })); fireEvent.click(screen.getByRole('button', { name: 'delete' })); expect(await screen.findByText('Error')).toBeVisible(); }); }); describe('with reset', () => { it('should reset with field array', async () => { let fieldsTemp: unknown[] = []; const App = () => { const { register, reset, control } = useForm({ defaultValues: { test: [{ value: 'default' }], }, }); const { fields, append } = useFieldArray({ name: 'test', control, }); fieldsTemp = fields; return (
{fields.map((field, index) => { return ( ); })}
); }; render(); fireEvent.click(screen.getByRole('button', { name: 'append' })); fireEvent.click(screen.getByRole('button', { name: 'reset' })); expect(fieldsTemp).toEqual([{ id: '5', value: 'default' }]); }); it('should reset with field array with shouldUnregister set to false', () => { const { result } = renderHook(() => { const { register, reset, control } = useForm({ defaultValues: { test: [{ value: 'default' }], }, }); const { fields, append } = useFieldArray({ name: 'test', control, }); return { register, reset, fields, append }; }); act(() => { result.current.append({ value: 'test' }); }); result.current.register('test.0.value'); act(() => { result.current.reset(); }); expect(result.current.fields).toEqual([{ id: '5', value: 'default' }]); act(() => { result.current.reset({ test: [{ value: 'data' }], }); }); expect(result.current.fields).toEqual([{ id: '7', value: 'data' }]); }); it('should reset with async', async () => { type FormValues = { test: { value: string; nestedArray: { value: string; }[]; }[]; }; const Nested = ({ index, control, }: { control: Control; index: number; }) => { const { fields } = useFieldArray({ name: `test.${index}.nestedArray` as const, control, }); return (
{fields.map((item, i) => ( ))}
); }; const Component = () => { const { register, reset, control } = useForm(); const { fields } = useFieldArray({ name: 'test', control, }); React.useEffect(() => { setTimeout(() => { reset({ test: [ { value: '1', nestedArray: [{ value: '2' }] }, { value: '3', nestedArray: [{ value: '4' }] }, ], }); }); }, [reset]); return (
{fields.map((item, i) => (
))}
); }; render(); await waitFor(() => expect(screen.getAllByRole('textbox')).toHaveLength(4), ); }); }); describe('with setValue', () => { it.each(['isDirty', 'dirtyFields'])( 'should set name to dirtyFieldRef if array field values are different with default value when formState.%s is defined', async (property) => { let setValue: any; let formState: any; const Component = () => { const { register, control, formState: tempFormState, setValue: tempSetValue, watch, } = useForm({ defaultValues: { test: [ { name: 'default' }, { name: 'default1' }, { name: 'default2' }, ], }, }); const { fields } = useFieldArray({ name: 'test', control }); watch(); setValue = tempSetValue; formState = tempFormState; formState[property]; return (
{fields.map((field, i) => ( ))}
); }; render(); await act(async () => { setValue( 'test', [ { name: 'default_update' }, { name: 'default1' }, { name: 'default2' }, ], { shouldDirty: true }, ); }); if (property === 'dirtyFields') { expect(formState.dirtyFields).toEqual({ test: [{ name: true }, { name: false }, { name: false }], }); } else { expect(formState.isDirty).toBeTruthy(); } }, ); it.each(['dirtyFields'])( 'should unset name from dirtyFieldRef if array field values are not different with default value when formState.%s is defined', (property) => { let setValue: any; let formState: any; const Component = () => { const { register, control, formState: tempFormState, setValue: tempSetValue, } = useForm({ defaultValues: { test: [ { name: 'default' }, { name: 'default1' }, { name: 'default2' }, ], }, }); const { fields } = useFieldArray({ name: 'test', control }); setValue = tempSetValue; formState = tempFormState; formState[property]; return (
{fields.map((field, i) => ( ))}
); }; render(); act(() => { setValue( 'test', [ { name: 'default_update' }, { name: 'default1' }, { name: 'default2' }, ], { shouldDirty: true }, ); }); if (property === 'dirtyFields') { expect(formState.dirtyFields).toEqual({ test: [{ name: true }, { name: false }, { name: false }], }); } else { expect(formState.isDirty).toBeTruthy(); } act(() => { setValue( 'test', [{ name: 'default' }, { name: 'default1' }, { name: 'default2' }], { shouldDirty: true }, ); }); expect(formState.dirtyFields).toEqual({ test: [ { name: false, }, { name: false, }, { name: false, }, ], }); expect(formState.isDirty).toBeFalsy(); }, ); it('should set nested field array correctly', async () => { type FormValues = { test: { firstName: string; lastName: string; keyValue: { name: string }[]; }[]; }; function NestedArray({ control, index, }: { control: Control; index: number; }) { const { fields } = useFieldArray({ name: `test.${index}.keyValue` as 'test.0.keyValue', control, }); return (
    {fields.map((item, i) => ( ( )} name={`test.${index}.keyValue.${i}.name` as const} control={control} /> ))}
); } function Component() { const { register, control, setValue } = useForm({ defaultValues: { test: [ { firstName: 'Bill', lastName: 'Luo', keyValue: [{ name: '1a' }, { name: '1c' }], }, ], }, }); const { fields } = useFieldArray({ control, name: 'test', }); return (
{fields.map((item, index) => { return (
); })}
); } render(); fireEvent.click(screen.getByRole('button', { name: 'setValue' })); const input = screen.getByLabelText( 'test.0.keyValue.0.name', ) as HTMLInputElement; expect(input.value).toEqual('2a'); expect( (screen.getByLabelText('test.0.firstName') as HTMLInputElement).value, ).toEqual('Bill'); }); }); describe('array of array fields', () => { it('should remove correctly with nested field array and set shouldUnregister to false', () => { type FormValues = { fieldArray: { value: string; nestedFieldArray: { value: string; }[]; }[]; }; const ArrayField = ({ arrayIndex, register, control, }: { arrayIndex: number; register: UseFormReturn['register']; arrayField: Partial; control: Control; }) => { const { fields, append, remove } = useFieldArray({ name: `fieldArray.${arrayIndex}.nestedFieldArray` as const, control, }); return (
{fields.map((nestedField, index) => (
))}
); }; const Component = () => { const { register, control } = useForm(); const { fields, append } = useFieldArray({ name: 'fieldArray', control, }); return (
{fields.map((field, index) => ( ))} ); }; render(); fireEvent.click( screen.getByRole('button', { name: 'Add array', }), ); fireEvent.click( screen.getByRole('button', { name: 'Add nested array', }), ); fireEvent.click( screen.getByRole('button', { name: 'Add nested array', }), ); fireEvent.click( screen.getAllByRole('button', { name: 'remove', })[0], ); fireEvent.click( screen.getAllByRole('button', { name: 'remove', })[0], ); expect(screen.getAllByRole('textbox').length).toEqual(1); }); it('should prepend correctly with default values on nested array fields', () => { type FormInputs = { nest: { test: { value: string; nestedArray: { value: string }[]; }[]; }; }; const ChildComponent = ({ index, control, }: { control: Control; index: number; }) => { const { fields } = useFieldArray({ name: `nest.test.${index}.nestedArray` as const, control, }); return ( <> {fields.map((item, i) => ( ))} ); }; const Component = () => { const { register, control } = useForm({ defaultValues: { nest: { test: [ { value: '1', nestedArray: [{ value: '2' }, { value: '3' }] }, { value: '4', nestedArray: [{ value: '5' }] }, ], }, }, }); const { fields, prepend } = useFieldArray({ name: 'nest.test', control, }); return ( <> {fields.map((item, i) => (
))} ); }; render(); expect(screen.getAllByRole('textbox')).toHaveLength(5); fireEvent.click(screen.getByRole('button', { name: /prepend/i })); expect(screen.getAllByRole('textbox')).toHaveLength(6); expect( (screen.getAllByRole('textbox')[0] as HTMLInputElement).value, ).toEqual('test'); }); it('should render correct amount of child array fields', async () => { type FormValues = { nest: { test: { value: string; nestedArray: { value: string; }[]; }[]; }; }; const ChildComponent = ({ index, control, }: { control: Control; index: number; }) => { const { fields } = useFieldArray({ name: `nest.test.${index}.nestedArray` as const, control, }); return (
{fields.map((item, i) => ( ))}
); }; const Component = () => { const { register, control } = useForm({ defaultValues: { nest: { test: [ { value: '1', nestedArray: [{ value: '2' }] }, { value: '3', nestedArray: [{ value: '4' }] }, ], }, }, }); const { fields, remove, append } = useFieldArray({ name: 'nest.test', control, }); return (
{fields.map((item, i) => (
))}
); }; render(); expect(screen.getAllByRole('textbox')).toHaveLength(4); fireEvent.click(screen.getByTestId('1')); expect(screen.getAllByRole('textbox')).toHaveLength(2); fireEvent.click(screen.getByRole('button', { name: /append/i })); expect(screen.getAllByRole('textbox')).toHaveLength(3); }); it('should populate all array fields with setValue when name match Field Array', () => { type FormInputs = { nest: { value: number; nestedArray: { value: number; }[]; }[]; }; const ChildComponent = ({ index, control, }: { control: Control; index: number; }) => { const { fields } = useFieldArray({ name: `nest.${index}.nestedArray` as const, control, }); return (
{fields.map((item, i) => ( ))}
); }; const Component = () => { const { register, control, setValue } = useForm(); const { fields } = useFieldArray({ name: 'nest', control, }); React.useEffect(() => { setValue('nest', [ { value: 1, nestedArray: [ { value: 11, }, ], }, { value: 2, nestedArray: [ { value: 21, }, ], }, ]); }, [setValue]); return (
{fields.map((item, i) => (
))}
); }; render(); const nestInput0 = screen.getByRole('textbox', { name: 'nest.0.value', }); const nestInput1 = screen.getByRole('textbox', { name: 'nest.1.value' }); const nestedArrayInput0 = screen.getByRole('textbox', { name: 'nest.0.nestedArray.0.value', }); const nestedArrayInput1 = screen.getByRole('textbox', { name: 'nest.1.nestedArray.0.value', }); expect(nestInput0).toHaveValue('1'); expect(nestedArrayInput0).toHaveValue('11'); expect(nestInput1).toHaveValue('2'); expect(nestedArrayInput1).toHaveValue('21'); }); it('should populate all array fields correctly with setValue', () => { type FormValues = { nest: { value: number; nestedArray: { value: number }[]; }[]; }; const ChildComponent = ({ index, control, }: { control: Control; index: number; }) => { const { fields } = useFieldArray({ name: `nest.${index}.nestedArray` as const, control, }); return (
{fields.map((item, i) => ( ))}
); }; const Component = () => { const { register, control, setValue } = useForm(); const { fields } = useFieldArray({ name: 'nest', control, }); React.useEffect(() => { setValue( 'nest', [ { value: 1, nestedArray: [ { value: 11, }, ], }, { value: 2, nestedArray: [ { value: 21, }, ], }, ], { shouldDirty: true }, ); }, [setValue]); return (
{fields.map((item, i) => (
))}
); }; render(); const nestInput0 = screen.getByRole('textbox', { name: 'nest.0.value' }); const nestInput1 = screen.getByRole('textbox', { name: 'nest.1.value' }); const nestedArrayInput0 = screen.getByRole('textbox', { name: 'nest.0.nestedArray.0.value', }); const nestedArrayInput1 = screen.getByRole('textbox', { name: 'nest.1.nestedArray.0.value', }); expect(nestInput0).toHaveValue('1'); expect(nestedArrayInput0).toHaveValue('11'); expect(nestInput1).toHaveValue('2'); expect(nestedArrayInput1).toHaveValue('21'); }); it('should worked with deep nested field array without chaining useFieldArray', () => { type FormValues = { nest: { value: string; nestedArray: { deepNest: { value: string }[] }; }[]; }; const ChildComponent = ({ index, control, }: { control: Control; index: number; }) => { const { fields, append } = useFieldArray({ name: `nest.${index}.nestedArray.deepNest` as const, control, }); return (
{fields.map((item, i) => ( ))}
); }; const Component = () => { const { register, control, setValue, reset } = useForm(); const { fields } = useFieldArray({ name: 'nest', control, }); React.useEffect(() => { reset({ nest: [ { value: '1', nestedArray: { deepNest: [ { value: '1', }, ], }, }, ], }); }, [reset]); return (
{fields.map((item, i) => (
))}
); }; render(); expect(screen.getAllByRole('textbox')).toHaveLength(2); const nestInput = screen.getByRole('textbox', { name: 'nest.0.value' }); const deepNestInput0 = screen.getByRole('textbox', { name: 'nest.0.nestedArray.deepNest.0.value', }); expect(nestInput).toHaveValue('1'); expect(deepNestInput0).toHaveValue('1'); fireEvent.click(screen.getByRole('button', { name: 'setValue' })); const deepNestInput1 = screen.getByRole('textbox', { name: 'nest.0.nestedArray.deepNest.1.value', }); const deepNestInput2 = screen.getByRole('textbox', { name: 'nest.0.nestedArray.deepNest.2.value', }); expect(screen.getByRole('textbox', { name: 'nest.0.value' })).toHaveValue( 'newV1', ); expect( screen.getByRole('textbox', { name: 'nest.0.nestedArray.deepNest.0.value', }), ).toHaveValue('new1'); expect(deepNestInput1).toHaveValue('new2'); expect(deepNestInput2).toHaveValue('new3'); fireEvent.click(screen.getByRole('button', { name: 'append' })); const deepNestInput3 = screen.getByRole('textbox', { name: 'nest.0.nestedArray.deepNest.3.value', }); expect(deepNestInput3).toHaveValue('test'); }); it('should allow append with deeply nested field array even with flat structure', async () => { const watchValue: unknown[] = []; const App = () => { const [data, setData] = React.useState({}); const { control, handleSubmit, watch } = useForm<{ test: { yourDetails: { firstName: string[]; lastName: string[]; }; }[]; }>(); const { fields, append } = useFieldArray({ control, name: 'test', }); watchValue.push(watch()); return (
{ setData(data); })} > {fields.map((field) => { return
; })}

{JSON.stringify(data)}

); }; render(); expect(watchValue.at(-1)).toEqual({ test: [] }); fireEvent.click(screen.getByRole('button', { name: 'append' })); expect(watchValue.at(-1)).toEqual({ test: [ { yourDetails: { firstName: ['test', 'test1'], lastName: ['test', 'test1'], }, }, ], }); fireEvent.click(screen.getByRole('button', { name: 'submit' })); expect( await screen.findByText( '{"test":[{"yourDetails":{"firstName":["test","test1"],"lastName":["test","test1"]}}]}', ), ).toBeVisible(); // Let's check all values of renders with implicitly the number of render (for each value) expect(watchValue).toMatchSnapshot(); }); }); describe('submit form', () => { it('should not leave defaultValues as empty array', async () => { let submitData: any; type FormValues = { test: { value: string; }[]; }; const Component = () => { const { register, control, handleSubmit } = useForm({ defaultValues: { test: [], }, }); const { fields } = useFieldArray({ control, name: 'test', }); const onSubmit: SubmitHandler = (data) => { submitData = data; }; return (
{fields.map((field, i) => ( ))}
); }; render(); fireEvent.click(screen.getByRole('button')); await waitFor(() => expect(submitData).toEqual({ test: [], }), ); }); }); it('should custom register append, prepend and insert inputs with values', () => { type FormValues = { test: { test: string; test1: string; test2: { test: string; }[]; }[]; }; const watchValues: unknown[] = []; const Component = () => { const { control, watch } = useForm({ defaultValues: { test: [], }, }); const { append, prepend, insert } = useFieldArray({ control, name: 'test', }); watchValues.push(watch('test')); React.useEffect(() => { append({ test: 'append', test1: 'append', test2: [], }); }, [append]); return (
); }; render(); expect(watchValues.at(-1)).toEqual([ { test: 'append', test1: 'append', test2: [], }, ]); fireEvent.click(screen.getByRole('button', { name: 'prepend' })); expect(watchValues.at(-1)).toEqual([ { test: 'prepend', test1: 'prepend', test2: [] }, { test: 'append', test1: 'append', test2: [], }, ]); fireEvent.click(screen.getByRole('button', { name: 'insert' })); expect(watchValues.at(-1)).toEqual([ { test: 'prepend', test1: 'prepend', test2: [] }, { test: 'insert', test1: 'insert', test2: [], }, { test: 'append', test1: 'append', test2: [], }, ]); fireEvent.click(screen.getByRole('button', { name: 'deep append' })); expect(watchValues.at(-1)).toEqual([ { test: 'prepend', test1: 'prepend', test2: [] }, { test: 'insert', test1: 'insert', test2: [], }, { test: 'append', test1: 'append', test2: [], }, { test: 'append', test1: '', test2: [ { test: 'test', }, ], }, ]); fireEvent.click(screen.getByRole('button', { name: 'deep prepend' })); expect(watchValues.at(-1)).toEqual([ { test: 'prepend', test1: '', test2: [ { test: 'test', }, ], }, { test: 'prepend', test1: 'prepend', test2: [] }, { test: 'insert', test1: 'insert', test2: [], }, { test: 'append', test1: 'append', test2: [], }, { test: 'append', test1: '', test2: [ { test: 'test', }, ], }, ]); fireEvent.click(screen.getByRole('button', { name: 'deep insert' })); expect(watchValues.at(-1)).toEqual([ { test: 'prepend', test1: '', test2: [ { test: 'test', }, ], }, { test: 'insert', test1: '', test2: [ { test: 'test', }, ], }, { test: 'prepend', test1: 'prepend', test2: [] }, { test: 'insert', test1: 'insert', test2: [], }, { test: 'append', test1: 'append', test2: [], }, { test: 'append', test1: '', test2: [ { test: 'test', }, ], }, ]); // Let's check all values of renders with implicitly the number of render (for each value) expect(watchValues).toMatchSnapshot(); }); it('should append multiple inputs correctly', () => { type FormValues = { test: { value: string; }[]; }; const watchedValue: unknown[] = []; const Component = () => { const { register, control, watch } = useForm({ defaultValues: { test: [ { value: 'data', }, ], }, }); const { fields, append } = useFieldArray({ control, name: 'test', }); watchedValue.push(watch()); return (
{fields.map((field, i) => ( ))}
); }; render(); expect(watchedValue.at(-1)).toEqual({ test: [ { value: 'data', }, ], }); fireEvent.click(screen.getByRole('button')); expect(watchedValue.at(-1)).toEqual({ test: [ { value: 'data', }, { value: 'test' }, { value: 'test1' }, ], }); // Let's check all values of renders with implicitly the number of render (for each value) expect(watchedValue).toMatchSnapshot(); }); it('should update field array defaultValues when invoke setValue', async () => { type FormValues = { names: { name: string; }[]; }; const result: unknown[] = []; const Child = () => { const { fields } = useFieldArray({ name: 'names', }); return ( <> {fields.map((item, index) => ( } /> ))} ); }; function Component() { const [hide, setHide] = React.useState(true); const methods = useForm({ defaultValues: { names: [{ name: 'will' }, { name: 'Mike' }], }, }); const { setValue, watch } = methods; result.push(watch()); return (
{hide && }
); } render(); expect(result.at(-1)).toEqual({ names: [ { name: 'will', }, { name: 'Mike', }, ], }); fireEvent.click(screen.getByRole('button', { name: 'Toggle hide' })); expect(screen.queryAllByRole('textbox')).toEqual([]); fireEvent.click(screen.getByRole('button', { name: 'Change value' })); expect(screen.queryByRole('textbox')).not.toBeInTheDocument(); expect(screen.queryByRole('textbox')).not.toBeInTheDocument(); fireEvent.click(screen.getByRole('button', { name: 'Toggle hide' })); expect(screen.queryByRole('textbox')).not.toBeInTheDocument(); expect(result.at(-1)).toEqual({ names: [] }); // Let's check all values of renders with implicitly the number of render (for each value) expect(result).toEqual([ { names: [ { name: 'will', }, { name: 'Mike', }, ], }, { names: [ { name: 'will', }, { name: 'Mike', }, ], }, { names: [ { name: 'will', }, { name: 'Mike', }, ], }, { names: [], }, { names: [], }, { names: [], }, ]); }); it('should unregister field array when shouldUnregister set to true', () => { type FormValues = { test: { value: string; }[]; }; const watchedValues: FormValues[] = []; const Child = ({ control, register, }: { show: boolean; control: Control; register: UseFormRegister; }) => { const { fields } = useFieldArray({ control, name: 'test', shouldUnregister: true, }); return ( <> {fields.map((field, i) => ( ))} ); }; const Component = () => { const { register, control, watch } = useForm({ defaultValues: { test: [{ value: 'test' }, { value: 'test1' }], }, }); const [show, setShow] = React.useState(true); watchedValues.push(watch()); return (
{show && } ); }; render(); expect(watchedValues.at(-1)).toEqual({ test: [{ value: 'test' }, { value: 'test1' }], }); fireEvent.click(screen.getByRole('button')); expect(watchedValues.at(-1)).toEqual({}); // Let's check all values of renders with implicitly the number of render (for each value) expect(watchedValues).toEqual([ { test: [ { value: 'test', }, { value: 'test1', }, ], }, { test: [ { value: 'test', }, { value: 'test1', }, ], }, { test: [ { value: 'test', }, { value: 'test1', }, ], }, {}, ]); }); it('should keep field values when field array gets unmounted and mounted', async () => { type FormValues = { test: { firstName: string }[]; }; const Test = ({ register, control, }: { register: UseFormRegister; control: Control; }) => { const { fields, append } = useFieldArray({ name: 'test', control, }); return (
{fields.map((field, i) => { return ( ); })}
); }; const App = () => { const { control, register } = useForm(); const [show, setShow] = React.useState(true); return ( <> {show && } ); }; render(); fireEvent.click(screen.getByRole('button', { name: 'append' })); fireEvent.click(screen.getByRole('button', { name: 'append' })); fireEvent.click(screen.getByRole('button', { name: 'show' })); expect(screen.queryByRole('textbox')).not.toBeInTheDocument(); fireEvent.click(screen.getByRole('button', { name: 'show' })); expect(screen.getAllByRole('textbox').length).toEqual(2); }); it('should append deep nested field array correctly with strict mode', async () => { function App() { const { control, register, handleSubmit } = useForm<{ test: { yourDetail: { firstName: string; lastName: string; }; }[]; }>(); const { fields, append } = useFieldArray({ name: 'test', control, }); return (
{fields.map((field, index) => { return (
); })}
); } render(); fireEvent.click(screen.getByRole('button', { name: 'Append' })); expect( (screen.getAllByRole('textbox')[0] as HTMLInputElement).value, ).toEqual('bill'); expect( (screen.getAllByRole('textbox')[1] as HTMLInputElement).value, ).toEqual('luo'); }); it('should not populate defaultValue when field array is already mounted', async () => { type FormValues = { root: { test: string; children: { name: string }[]; }[]; }; const Child = ({ control, index, register, }: { control: Control; index: number; register: UseFormRegister; }) => { const { fields, append } = useFieldArray({ name: `root.${index}.children`, control, }); return (
{fields.map((field, k) => { return (
); })}
); }; const App = () => { const { register, control } = useForm({ defaultValues: { root: [ { test: 'default', children: [ { name: 'child of index 0', }, ], }, { test: 'default1', children: [], }, ], }, }); const { fields, swap } = useFieldArray({ control, name: 'root', }); return (
{fields.map((field, index) => { return (
); })}
); }; render(); fireEvent.click(screen.getByRole('button', { name: 'swap' })); fireEvent.click(screen.getAllByRole('button', { name: 'append' })[0]); expect( (screen.getAllByRole('textbox')[0] as HTMLInputElement).value, ).toEqual('default1'); expect( (screen.getAllByRole('textbox')[1] as HTMLInputElement).value, ).toEqual('test'); expect( (screen.getAllByRole('textbox')[2] as HTMLInputElement).value, ).toEqual('default'); expect( (screen.getAllByRole('textbox')[3] as HTMLInputElement).value, ).toEqual('child of index 0'); }); it('should update field array correctly when unmounted field', () => { type FormValues = { nest: { value: string; nested: { value: string; }[]; }[]; }; function Nested({ control, register, index, }: { control: Control; register: UseFormRegister; index: number; }) { const { fields } = useFieldArray({ control, name: `nest.${index}.nested`, }); return ( <> {fields.map((field, i) => ( ))} ); } function App() { const { control, register, setValue, getValues } = useForm({ defaultValues: { nest: [ { value: '0', nested: [{ value: '0sub1' }, { value: '0sub2' }] }, { value: '1', nested: [{ value: '1sub1' }, { value: '1sub2' }] }, { value: '2', nested: [{ value: '2sub1' }, { value: '2sub2' }] }, ], }, }); const { fields, remove } = useFieldArray({ control, name: 'nest', }); function handleAddInner() { setValue(`nest.1.nested`, [ ...getValues(`nest.1.nested`), { value: `1sub-new` }, ]); } return ( <> {fields.map((field, index) => (
))} ); } render(); expect(screen.getAllByRole('textbox').length).toEqual(9); fireEvent.click(screen.getByRole('button', { name: 'remove1' })); expect(screen.getAllByRole('textbox').length).toEqual(6); fireEvent.click(screen.getByRole('button', { name: 'set' })); expect(screen.getAllByRole('textbox').length).toEqual(7); expect( (screen.getAllByRole('textbox')[6] as HTMLInputElement).value, ).toEqual('1sub-new'); }); it('should update field array correctly with async invocation', async () => { type FormValues = { items: { id: string; name: string }[]; }; let controlObj: any = {}; const App = () => { const { register, control } = useForm({ mode: 'onChange', defaultValues: { items: [{ name: 'one' }, { name: 'two' }], }, }); controlObj = control; const { fields, remove, insert } = useFieldArray({ control, name: 'items', }); return (
{fields.map((field, index) => { return (
); })}
); }; render(); fireEvent.click(screen.getAllByRole('button', { name: 'copy' })[0]); fireEvent.click(screen.getAllByRole('button', { name: 'remove' })[0]); expect(controlObj._fields.items.length).toEqual(2); }); it('should avoid omit keyName when defaultValues contains keyName attribute', () => { let getValuesMethod: Function = noop; const App = () => { const { control, getValues } = useForm({ defaultValues: { test: [{ id: '1234', test: 'data' }], }, }); getValuesMethod = getValues; useFieldArray({ control, name: 'test', }); return null; }; render(); expect(getValuesMethod()).toEqual({ test: [{ id: '1234', test: 'data' }], }); }); describe('with rules', () => { it('should validate the minLength of the entire field array after submit and correct accordingly', async () => { const App = () => { const { control, handleSubmit, formState: { errors }, } = useForm({ defaultValues: { test: [{ test: '' }], }, }); const { append } = useFieldArray({ control, name: 'test', rules: { minLength: { value: 2, message: 'Min length should be 2', }, }, }); return (

{errors.test?.root?.message}

); }; render(); await act(async () => { fireEvent.click(screen.getByRole('button', { name: 'submit' })); }); screen.getByText('Min length should be 2'); await act(async () => { fireEvent.click(screen.getByRole('button', { name: 'append' })); fireEvent.click(screen.getByRole('button', { name: 'append' })); }); expect(screen.queryByAltText('Min length should be 2')).toBeNull(); }); it('should validate with custom validation after submit and correct accordingly', async () => { const App = () => { const { control, handleSubmit, formState: { errors }, } = useForm({ defaultValues: { test: [{ test: '' }], }, }); const { append } = useFieldArray({ control, name: 'test', rules: { validate: (values) => { if (Array.isArray(values) && values.length < 2) { return 'Min length should be 2'; } return true; }, }, }); return (

{errors.test?.root?.message}

); }; render(); await act(async () => { fireEvent.click(screen.getByRole('button', { name: 'submit' })); }); screen.getByText('Min length should be 2'); await act(async () => { fireEvent.click(screen.getByRole('button', { name: 'append' })); fireEvent.click(screen.getByRole('button', { name: 'append' })); }); expect(screen.queryByAltText('Min length should be 2')).toBeNull(); }); it('should validate the maxLength of the entire field array after submit and correct accordingly', async () => { const App = () => { const { control, handleSubmit, formState: { errors }, } = useForm({ defaultValues: { test: [{ test: '' }, { test: '' }, { test: '' }, { test: '' }], }, }); const { remove } = useFieldArray({ control, name: 'test', rules: { maxLength: { value: 2, message: 'Max length should be 2', }, }, }); return (

{errors.test?.root?.message}

); }; render(); await act(async () => { fireEvent.click(screen.getByRole('button', { name: 'submit' })); }); screen.getByText('Max length should be 2'); await act(async () => { fireEvent.click(screen.getByRole('button', { name: 'remove' })); }); expect(screen.queryByAltText('Max length should be 2')).toBeNull(); }); it('should respect the validation mode and trigger validation after each field array action', async () => { const App = () => { const { control, handleSubmit, formState: { errors }, } = useForm({ defaultValues: { test: [{ test: '' }, { test: '' }, { test: '' }, { test: '' }], }, mode: 'onChange', }); const { remove, append } = useFieldArray({ control, name: 'test', rules: { maxLength: { value: 2, message: 'Max length should be 2', }, }, }); return (

{errors.test?.root?.message}

); }; render(); expect(screen.queryByAltText('Max length should be 2')).toBeNull(); await act(async () => { fireEvent.click(screen.getByRole('button', { name: 'append' })); }); screen.getByText('Max length should be 2'); await act(async () => { fireEvent.click(screen.getByRole('button', { name: 'remove' })); }); expect(screen.queryByAltText('Max length should be 2')).toBeNull(); }); it('should no longer validate when unmounted', async () => { const ArrayField = () => { const { fields } = useFieldArray({ name: 'array', rules: { required: { value: true, message: 'This is required', }, minLength: { value: 2, message: 'Min length should be 2', }, }, }); return (
{fields.map((item, index) => ( } /> ))}
); }; const App = () => { const [displayArray, setDisplayArray] = useState(true); const formValues = useForm({ defaultValues: { array: [{ value: '' }] }, }); return (
{displayArray && }

{formValues.formState.errors.array?.root?.message}

); }; render(); expect( screen.queryByText('Min length should be 2'), ).not.toBeInTheDocument(); await act(async () => { fireEvent.click(screen.getByRole('button', { name: /submit/i })); }); expect(screen.queryByText('Min length should be 2')).toBeInTheDocument(); await act(async () => { fireEvent.click(screen.getByRole('button', { name: /toggle/i })); }); await act(async () => { fireEvent.click(screen.getByRole('button', { name: /submit/i })); }); expect( screen.queryByText('Min length should be 2'), ).not.toBeInTheDocument(); }); it('should not conflict with field level error', async () => { const App = () => { const { control, handleSubmit, formState: { errors }, register, } = useForm({ defaultValues: { test: [{ test: '' }, { test: '' }, { test: '' }, { test: '' }], }, mode: 'onChange', }); const { remove, append, fields } = useFieldArray({ control, name: 'test', rules: { maxLength: { value: 2, message: 'Max length should be 2', }, }, }); return (
{fields.map((field, index) => { return (

{errors.test?.[index]?.test?.message}

); })}

{errors.test?.root?.message}

); }; render(); expect(screen.queryByAltText('Max length should be 2')).toBeNull(); expect(screen.queryByAltText('This is required')).toBeNull(); await act(async () => { fireEvent.change(screen.getAllByRole('textbox')[0], { target: { value: '1', }, }); }); await act(async () => { fireEvent.change(screen.getAllByRole('textbox')[0], { target: { value: '', }, }); }); screen.getByText('This is required'); await act(async () => { fireEvent.click(screen.getByRole('button', { name: 'append' })); }); expect(screen.queryByAltText('Max length should be 2')).toBeNull(); await act(async () => { fireEvent.click(screen.getByRole('button', { name: 'remove' })); }); expect(screen.queryByAltText('Max length should be 2')).toBeNull(); }); it('should not throw error when required is not defined but minLength', async () => { const App = () => { const { control, handleSubmit, formState: { errors }, register, } = useForm<{ test: { test: string }[] }>({ defaultValues: { test: [], }, }); const { fields } = useFieldArray({ control, name: 'test', rules: { maxLength: { value: 2, message: 'Max length should be 2', }, }, }); return (
{fields.map((field, index) => { return (

{errors.test?.[index]?.test?.message}

); })}

{errors.test?.root?.message}

); }; render(); await act(async () => { fireEvent.click(screen.getByRole('button')); }); expect(screen.queryByAltText('Max length should be 2')).toBeNull(); }); it('should throw error when required is defined', async () => { const App = () => { const { control, handleSubmit, formState: { errors }, register, } = useForm<{ test: { test: string }[] }>({ defaultValues: { test: [], }, }); const { fields } = useFieldArray({ control, name: 'test', rules: { required: 'Please enter some data', }, }); return (
{fields.map((field, index) => { return (

{errors.test?.[index]?.test?.message}

); })}

{errors.test?.root?.message}

); }; render(); await act(async () => { fireEvent.click(screen.getByRole('button')); }); expect(screen.queryByAltText('Please enter some data')).toBeNull(); }); }); describe('with nested field array ', () => { type FormValues = { fieldArray: { value: string; nestedFieldArray: { value: string; }[]; }[]; }; const ArrayField = ({ arrayIndex, register, control, }: { arrayIndex: number; register: UseFormReturn['register']; arrayField: Partial; control: Control; }) => { const { fields, append } = useFieldArray({ name: `fieldArray.${arrayIndex}.nestedFieldArray` as const, control, rules: { required: 'This is required', minLength: { value: 3, message: 'Min length of 3', }, }, }); return (
{fields.map((nestedField, index) => (
))}
); }; it('should report field array error at the nested useFieldArray level when form submitted', async () => { const Component = () => { const { register, control, handleSubmit, formState: { errors }, } = useForm(); const { fields, append } = useFieldArray({ name: 'fieldArray', control, }); return (
{fields.map((field, index) => { return (

{errors?.fieldArray?.[0]?.nestedFieldArray?.root?.message}

); })}
); }; render(); await act(async () => { fireEvent.click(screen.getByRole('button', { name: 'append' })); }); await act(async () => { fireEvent.click(screen.getByRole('button', { name: 'submit' })); }); screen.getByText('This is required'); }); it('should report field array error at the nested useFieldArray level during field level action', async () => { const Component = () => { const { register, control, handleSubmit, formState: { errors }, } = useForm({ mode: 'onChange', }); const { fields, append } = useFieldArray({ name: 'fieldArray', control, }); return (
{fields.map((field, index) => { return (

{errors?.fieldArray?.[0]?.nestedFieldArray?.root?.message}

); })}
); }; render(); await act(async () => { fireEvent.click(screen.getByRole('button', { name: 'append' })); }); await act(async () => { fireEvent.click( screen.getByRole('button', { name: 'Add nested array' }), ); }); screen.getByText('Min length of 3'); }); }); it('should update isValid correctly with rules props and inline validation', async () => { const App = () => { const { control, register, formState: { isValid }, } = useForm({ defaultValues: { test: [{ value: '1' }], }, }); const { fields, append } = useFieldArray({ control, name: 'test', rules: { required: true, }, }); return (
{fields.map((field, index) => ( ))}

{isValid ? 'valid' : 'invalid'}

); }; render(); await waitFor(() => { screen.getByText('valid'); }); fireEvent.click(screen.getByRole('button')); await waitFor(() => { screen.getByText('invalid'); }); }); describe('with formState observers', () => { it('should trigger reRender when user subscribes to root formState', async () => { type FormValues = { test: { value: string }[] }; const FieldArray = ({ register, control, }: { register: UseFormRegister; control: Control; }) => { const { fields, append } = useFieldArray({ control, name: 'test', }); return ( <> {fields.map((field, i) => ( ))} ); }; let renderCount = 0; const Component = () => { const { register, control, formState } = useForm(); formState.isDirty; formState.dirtyFields; formState.errors; renderCount++; return (
); }; render(); fireEvent.click(screen.getByRole('button', { name: /append/i })); await waitFor(() => expect(renderCount).toEqual(3)); }); it('should trigger reRender on components that subscribe to useFieldArray fieldState', async () => { type FormValues = { test: { value: string }[] }; let rootRenderCount = 0; let observerRenderCount = 0; const FieldArray = ({ register, control, }: { register: UseFormRegister; control: Control; }) => { const { fields, append } = useFieldArray({ control, name: 'test', }); return ( <> {fields.map((field, i) => ( ))} ); }; const Observer = ({ control }: { control: Control }) => { const { isDirty, dirtyFields, errors } = useFormState({ name: 'test', control, }); observerRenderCount++; return

{JSON.stringify({ isDirty, dirtyFields, errors })}

; }; const Component = () => { const { register, control } = useForm(); rootRenderCount++; return (
); }; render(); fireEvent.click(screen.getByRole('button', { name: /append/i })); await waitFor(() => { expect(rootRenderCount).toEqual(2); expect(observerRenderCount).toEqual(3); }); }); it('should unmount field array and remove its reference with shouldUnregister: true', () => { type FormValues = { type: string; array: { data: string; }[]; }; let array: { data: string }[] = []; function FieldArray({ control }: { control: Control }) { useFieldArray({ name: 'array' as const, control, shouldUnregister: true, }); return null; } function App() { const methods = useForm({ defaultValues: { type: 'NO_CART', array: [], }, shouldUnregister: true, }); const [toggle, setToggle] = useState(false); const { control, watch } = methods; array = watch('array'); return ( <> ); }; const NotObserver = ({ control }: { control: Control }) => { const { isDirty, dirtyFields, errors } = useFormState({ name: 'other', control, }); notObserverRenderCount++; return

{JSON.stringify({ isDirty, dirtyFields, errors })}

; }; const Component = () => { const { register, control } = useForm(); rootRenderCount++; return (
); }; render(); fireEvent.click(screen.getByRole('button', { name: /append/i })); expect(rootRenderCount).toEqual(2); expect(notObserverRenderCount).toEqual(2); }); }); }); describe('useFieldArray with checkbox', () => { it('should correctly duplicate checkbox items with their values', async () => { const App = () => { const methods = useForm<{ checkboxes: { label: string; value: boolean; }[]; }>({ defaultValues: { checkboxes: [ { label: 'Option 1', value: true }, { label: 'Option 2', value: true }, ], }, }); const { register, control } = methods; const { fields, insert } = useFieldArray({ control, name: 'checkboxes', rules: { minLength: { value: 1, message: 'At least one checkbox is required', }, }, }); const handleDuplicate = (index: number) => { const currentItem = methods.getValues(`checkboxes.${index}`); insert(index + 1, { label: `${currentItem.label} (copy)`, value: currentItem.value, }); }; return (
{fields.map((field, index) => ( ))}
); }; render(); expect(screen.getByTestId('checkbox-0')).toBeChecked(); expect(screen.getByTestId('checkbox-1')).toBeChecked(); fireEvent.click(screen.getByTestId('duplicate-button-0')); await waitFor(() => { expect(screen.getByText('Option 1 (copy)')).toBeInTheDocument(); expect(screen.getByTestId('checkbox-1')).toBeChecked(); }); fireEvent.click(screen.getByTestId('duplicate-button-2')); await waitFor(() => { expect(screen.getByText('Option 2 (copy)')).toBeInTheDocument(); expect(screen.getByTestId('checkbox-2')).toBeChecked(); }); const checkboxes = screen.getAllByRole('checkbox'); expect(checkboxes).toHaveLength(4); checkboxes.forEach((checkbox) => { expect(checkbox).toBeChecked(); }); }); it('should maintain correct checkbox states after multiple duplications', async () => { const App = () => { const methods = useForm<{ checkboxes: { label: string; value: boolean; }[]; }>({ defaultValues: { checkboxes: [ { label: 'Option 1', value: true }, { label: 'Option 2', value: false }, ], }, }); const { register, control } = methods; const { fields, insert } = useFieldArray({ control, name: 'checkboxes', rules: { minLength: { value: 1, message: 'At least one checkbox is required', }, }, }); const handleDuplicate = (index: number) => { const currentItem = methods.getValues(`checkboxes.${index}`); insert(index + 1, { label: `${currentItem.label} (copy)`, value: currentItem.value, }); }; return (
{fields.map((field, index) => ( ))}
); }; render(); expect(screen.getByTestId('checkbox-0')).toBeChecked(); expect(screen.getByTestId('checkbox-1')).not.toBeChecked(); fireEvent.click(screen.getByTestId('duplicate-button-0')); await waitFor(() => { expect(screen.getByText('Option 1 (copy)')).toBeInTheDocument(); expect(screen.getByTestId('checkbox-1')).toBeChecked(); }); fireEvent.click(screen.getByTestId('checkbox-1')); fireEvent.click(screen.getByTestId('duplicate-button-1')); await waitFor(() => { const checkboxes = screen.getAllByRole('checkbox'); expect(checkboxes).toHaveLength(4); expect(checkboxes[0]).toBeChecked(); // Option 1 expect(checkboxes[1]).not.toBeChecked(); // Option 1 (copy) expect(checkboxes[2]).not.toBeChecked(); // Option 1 (copy) (copy) expect(checkboxes[3]).not.toBeChecked(); // Option 2 }); }); });