fix: create fieldMeta on async validation for fields with errors

.changeset/shy-otters-give.md

@@ -0,0 +1,5 @@
+---
+'@tanstack/form-core': patch
+---
+
+fix: create fieldMeta on async validation for fields with errors

packages/form-core/src/FormApi.ts

@@ -1879,16 +1879,20 @@ export class FormApi<
           }
           const errorMapKey = getErrorMapKey(validateObj.cause)
 
-          for (const field of Object.keys(
-            this.state.fieldMeta,
-          ) as DeepKeys<TFormData>[]) {
-            if (this.baseStore.state.fieldMetaBase[field] === undefined) {
+          const allFieldsToProcess = new Set([
+            ...Object.keys(this.state.fieldMeta),
+            ...Object.keys(fieldErrorsFromFormValidators || {}),
+          ] as DeepKeys<TFormData>[])
+
+          for (const field of allFieldsToProcess) {
+            if (
+              this.baseStore.state.fieldMetaBase[field] === undefined &&
+              !fieldErrorsFromFormValidators?.[field]
+            ) {
               continue
             }
 
-            const fieldMeta = this.getFieldMeta(field)
-            if (!fieldMeta) continue
-
+            const fieldMeta = this.getFieldMeta(field) ?? defaultFieldMeta
             const {
               errorMap: currentErrorMap,
               errorSourceMap: currentErrorMapSource,
@@ -1910,7 +1914,7 @@ export class FormApi<
               // eslint-disable-next-line @typescript-eslint/no-unnecessary-condition
               currentErrorMap?.[errorMapKey] !== newErrorValue
             ) {
-              this.setFieldMeta(field, (prev) => ({
+              this.setFieldMeta(field, (prev = defaultFieldMeta) => ({
                 ...prev,
                 errorMap: {
                   ...prev.errorMap,

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

@@ -1873,6 +1873,37 @@ describe('form api', () => {
     expect(formSubmit).toHaveBeenCalledOnce()
   })
 
+  it('should create field meta from form async submit validation errors', async () => {
+    vi.useFakeTimers()
+
+    const form = new FormApi({
+      defaultValues: {
+        age: 0,
+      },
+      validators: {
+        onSubmitAsync: async ({ value }) => {
+          await sleep(1)
+          return value.age > 0
+            ? undefined
+            : { fields: { age: 'age must be greater than 0' } }
+        },
+      },
+      asyncDebounceMs: 1,
+    })
+
+    form.mount()
+
+    expect(form.state.fieldMeta.age).toBeUndefined()
+
+    form.handleSubmit()
+    await vi.runAllTimersAsync()
+
+    expect(form.state.fieldMeta.age).toBeDefined()
+    expect(form.state.fieldMeta.age?.errorMap.onSubmit).toBe(
+      'age must be greater than 0',
+    )
+  })
+
   it('should run all types of async validation on fields during submit', async () => {
     vi.useFakeTimers()