fix: form's valid state should be up to date (#475)

packages/form-core/src/FormApi.ts

@@ -134,8 +134,10 @@ export class FormApi<TFormData, ValidatorType> {
             (field) => field?.isValidating,
           )
 
-          const isFieldsValid = !fieldMetaValues.some((field) =>
-            isNonEmptyArray(field?.errors),
+          const isFieldsValid = !fieldMetaValues.some(
+            (field) =>
+              field?.errorMap &&
+              isNonEmptyArray(Object.values(field.errorMap).filter(Boolean)),
           )
 
           const isTouched = fieldMetaValues.some((field) => field?.isTouched)

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

@@ -1,6 +1,7 @@
 import { expect } from 'vitest'
 
 import { FormApi } from '../FormApi'
+import { FieldApi } from '../FieldApi'
 
 describe('form api', () => {
   it('should get default form state', () => {
@@ -267,4 +268,35 @@ describe('form api', () => {
 
     expect(form.getFieldValue('name')).toEqual('two')
   })
+
+  it("form's valid state should be work fine", () => {
+    const form = new FormApi({
+      defaultValues: {
+        name: '',
+      },
+    })
+
+    const field = new FieldApi({
+      form,
+      name: 'name',
+      onChange: (v) => (v.length > 0 ? undefined : 'required'),
+    })
+
+    field.mount()
+
+    field.handleChange('one')
+
+    expect(form.state.isFieldsValid).toEqual(true)
+    expect(form.state.canSubmit).toEqual(true)
+
+    field.handleChange('')
+
+    expect(form.state.isFieldsValid).toEqual(false)
+    expect(form.state.canSubmit).toEqual(false)
+
+    field.handleChange('two')
+
+    expect(form.state.isFieldsValid).toEqual(true)
+    expect(form.state.canSubmit).toEqual(true)
+  })
 })