feat: extend form.setErrorMap to spread errors in fields

packages/form-core/src/FormApi.ts

@@ -513,7 +513,7 @@ export type BaseFormState<
   /**
    * The error map for the form itself.
    */
-  errorMap: FormValidationErrorMap<
+  errorMap: ValidationErrorMap<
     UnwrapFormValidateOrFn<TOnMount>,
     UnwrapFormValidateOrFn<TOnChange>,
     UnwrapFormAsyncValidateOrFn<TOnChangeAsync>,
@@ -2122,7 +2122,8 @@ export class FormApi<
    * Updates the form's errorMap
    */
   setErrorMap(
-    errorMap: ValidationErrorMap<
+    errorMap: FormValidationErrorMap<
+      TFormData,
       UnwrapFormValidateOrFn<TOnMount>,
       UnwrapFormValidateOrFn<TOnChange>,
       UnwrapFormAsyncValidateOrFn<TOnChangeAsync>,
@@ -2133,13 +2134,50 @@ export class FormApi<
       UnwrapFormAsyncValidateOrFn<TOnServer>
     >,
   ) {
-    this.baseStore.setState((prev) => ({
-      ...prev,
-      errorMap: {
-        ...prev.errorMap,
-        ...errorMap,
-      },
-    }))
+    batch(() => {
+      Object.entries(errorMap).forEach(([key, value]) => {
+        const errorMapKey = key as ValidationErrorMapKeys
+
+        if (isGlobalFormValidationError(value)) {
+          const { formError, fieldErrors } = normalizeError<TFormData>(value)
+
+          for (const fieldName of Object.keys(
+            this.fieldInfo,
+          ) as DeepKeys<TFormData>[]) {
+            const fieldMeta = this.getFieldMeta(fieldName)
+            if (!fieldMeta) continue
+
+            this.setFieldMeta(fieldName, (prev) => ({
+              ...prev,
+              errorMap: {
+                ...prev.errorMap,
+                [errorMapKey]: fieldErrors?.[fieldName],
+              },
+              errorSourceMap: {
+                ...prev.errorSourceMap,
+                [errorMapKey]: 'form',
+              },
+            }))
+          }
+
+          this.baseStore.setState((prev) => ({
+            ...prev,
+            errorMap: {
+              ...prev.errorMap,
+              [errorMapKey]: formError,
+            },
+          }))
+        } else {
+          this.baseStore.setState((prev) => ({
+            ...prev,
+            errorMap: {
+              ...prev.errorMap,
+              [errorMapKey]: value,
+            },
+          }))
+        }
+      })
+    })
   }
 
   /**
@@ -2157,7 +2195,7 @@ export class FormApi<
         | UnwrapFormAsyncValidateOrFn<TOnSubmitAsync>
         | UnwrapFormAsyncValidateOrFn<TOnServer>
       >
-      errorMap: FormValidationErrorMap<
+      errorMap: ValidationErrorMap<
         UnwrapFormValidateOrFn<TOnMount>,
         UnwrapFormValidateOrFn<TOnChange>,
         UnwrapFormAsyncValidateOrFn<TOnChangeAsync>,

packages/form-core/src/types.ts

@@ -55,6 +55,7 @@ export type ValidationErrorMapSource = {
  * @private
  */
 export type FormValidationErrorMap<
+  TFormData = unknown,
   TOnMountReturn = unknown,
   TOnChangeReturn = unknown,
   TOnChangeAsyncReturn = unknown,
@@ -64,10 +65,19 @@ export type FormValidationErrorMap<
   TOnSubmitAsyncReturn = unknown,
   TOnServerReturn = unknown,
 > = {
-  onMount?: TOnMountReturn
-  onChange?: TOnChangeReturn | TOnChangeAsyncReturn
-  onBlur?: TOnBlurReturn | TOnBlurAsyncReturn
-  onSubmit?: TOnSubmitReturn | TOnSubmitAsyncReturn
+  onMount?: TOnMountReturn | GlobalFormValidationError<TFormData>
+  onChange?:
+    | TOnChangeReturn
+    | TOnChangeAsyncReturn
+    | GlobalFormValidationError<TFormData>
+  onBlur?:
+    | TOnBlurReturn
+    | TOnBlurAsyncReturn
+    | GlobalFormValidationError<TFormData>
+  onSubmit?:
+    | TOnSubmitReturn
+    | TOnSubmitAsyncReturn
+    | GlobalFormValidationError<TFormData>
   onServer?: TOnServerReturn
 }
 

packages/form-core/tests/FormApi.spec.ts

@@ -2285,6 +2285,37 @@ describe('form api', () => {
     expect(form.state.errorMap.onChange).toEqual('other validation error')
   })
 
+  it('should spread errors in fields when setErrorMap receives a global form validation error', () => {
+    const form = new FormApi({
+      defaultValues: { name: '', interests: [] as { label: string }[] },
+    })
+    form.mount()
+
+    const field = new FieldApi({ form, name: 'name' })
+    field.mount()
+
+    const arrayElementField = new FieldApi({ form, name: 'interests[0].label' })
+    arrayElementField.mount()
+
+    form.setErrorMap({
+      onChange: {
+        form: 'global error',
+        fields: {
+          name: 'name is required',
+          'interests[0].label': 'label is required',
+        },
+      },
+      onBlur: 'Form Error' as never,
+    })
+
+    expect(form.state.errorMap.onChange).toEqual('global error')
+    expect(form.state.errorMap.onBlur).toEqual('Form Error')
+    expect(field.getMeta().errorMap.onChange).toEqual('name is required')
+    expect(arrayElementField.getMeta().errorMap.onChange).toEqual(
+      'label is required',
+    )
+  })
+
   it("should set errors for the fields from the form's onSubmit validator", async () => {
     const form = new FormApi({
       defaultValues: {

packages/form-core/tests/FormApi.test-d.ts

@@ -2,6 +2,7 @@ import { expectTypeOf, it } from 'vitest'
 import { z } from 'zod'
 import { FormApi } from '../src'
 import type {
+  GlobalFormValidationError,
   StandardSchemaV1Issue,
   ValidationError,
   ValidationErrorMap,
@@ -118,11 +119,13 @@ it('should only have form-level error types returned from parseFieldValuesWithSc
 })
 
 it("should allow setting manual errors according to the validator's return type", () => {
+  type FormData = {
+    firstName: string
+    lastName: string
+  }
+
   const form = new FormApi({
-    defaultValues: {
-      firstName: '',
-      lastName: '',
-    },
+    defaultValues: {} as FormData,
     validators: {
       onChange: () => ['onChange'] as const,
       onMount: () => 10 as const,
@@ -134,28 +137,67 @@ it("should allow setting manual errors according to the validator's return type"
     },
   })
 
+  form.setErrorMap({
+    onMount: 10,
+    onChange: ['onChange'],
+  })
+
   expectTypeOf(form.setErrorMap).parameter(0).toEqualTypeOf<{
-    onMount: 10 | undefined
-    onChange: readonly ['onChange'] | 'onChangeAsync' | undefined
-    onBlur: { onBlur: true; onBlurNumber: number } | 'onBlurAsync' | undefined
-    onSubmit: 'onSubmit' | 'onSubmitAsync' | undefined
+    onMount: 10 | undefined | GlobalFormValidationError<FormData>
+    onChange:
+      | readonly ['onChange']
+      | 'onChangeAsync'
+      | undefined
+      | GlobalFormValidationError<FormData>
+    onBlur:
+      | { onBlur: true; onBlurNumber: number }
+      | 'onBlurAsync'
+      | undefined
+      | GlobalFormValidationError<FormData>
+    onSubmit:
+      | 'onSubmit'
+      | 'onSubmitAsync'
+      | undefined
+      | GlobalFormValidationError<FormData>
     onServer: undefined
   }>
 })
 
-it('should not allow setting manual errors if no validator is specified', () => {
+it('should allow setting field errors from the global form error map', () => {
+  type FormData = {
+    firstName: string
+    lastName: string
+  }
+
   const form = new FormApi({
-    defaultValues: {
-      firstName: '',
-      lastName: '',
+    defaultValues: {} as FormData,
+  })
+
+  form.setErrorMap({
+    onChange: {
+      fields: {
+        firstName: 'error',
+        // @ts-expect-error
+        nonExistentField: 'error',
+      },
     },
   })
+})
+
+it('should not allow setting manual errors if no validator is specified', () => {
+  type FormData = {
+    firstName: string
+    lastName: string
+  }
+  const form = new FormApi({
+    defaultValues: {} as FormData,
+  })
 
   expectTypeOf(form.setErrorMap).parameter(0).toEqualTypeOf<{
-    onMount: undefined
-    onChange: undefined
-    onBlur: undefined
-    onSubmit: undefined
+    onMount: undefined | GlobalFormValidationError<FormData>
+    onChange: undefined | GlobalFormValidationError<FormData>
+    onBlur: undefined | GlobalFormValidationError<FormData>
+    onSubmit: undefined | GlobalFormValidationError<FormData>
     onServer: undefined
   }>
 })