From 01ee70b1d20b914f76bd8a015943f1d67886da6b Mon Sep 17 00:00:00 2001
From: easeurmind <64529155+restareaByWeezy@users.noreply.github.com>
Date: Mon, 23 Mar 2026 16:18:18 +0900
Subject: [PATCH 1/2] fix(form-core): run field validators on re-submission to
 clear stale errors

When a field has an onBlur validator that produces an error, subsequent
form submission attempts are blocked by a canSubmit check that runs
before validateAllFields. This means stale onBlur errors (e.g. from a
field that is no longer invalid) prevent re-submission.

Fix: on re-submission attempts (submissionAttempts > 1), skip the early
canSubmit return so validateAllFields can re-run all field validators for
the submit cause. Stale errors are cleared and the isFieldsValid check
below handles the invalidity gate correctly.

First-submission behavior (submissionAttempts <= 1) is unchanged so
existing canSubmit semantics (e.g. onMount errors) are preserved.

Fixes #2034
---
 packages/form-core/src/FormApi.ts        | 19 +++++++---
 packages/form-core/tests/FormApi.spec.ts | 47 ++++++++++++++++++++++++
 2 files changed, 60 insertions(+), 6 deletions(-)

diff --git a/packages/form-core/src/FormApi.ts b/packages/form-core/src/FormApi.ts
index 2317fb2b9..a7e4fdaae 100644
--- a/packages/form-core/src/FormApi.ts
+++ b/packages/form-core/src/FormApi.ts
@@ -2105,12 +2105,19 @@ export class FormApi<
       submitMeta ?? (this.options.onSubmitMeta as TSubmitMeta)
 
     if (!this.state.canSubmit && !this._devtoolsSubmissionOverride) {
-      this.options.onSubmitInvalid?.({
-        value: this.state.values,
-        formApi: this,
-        meta: submitMetaArg,
-      })
-      return
+      // On re-submission (submissionAttempts > 1), skip the early return so
+      // validateAllFields can re-run and clear stale field errors (e.g. from a
+      // previous onBlur validation that is no longer relevant). The
+      // isFieldsValid check below will call onSubmitInvalid if the form is
+      // still invalid after re-validation.
+      if (this.baseStore.state.submissionAttempts <= 1) {
+        this.options.onSubmitInvalid?.({
+          value: this.state.values,
+          formApi: this,
+          meta: submitMetaArg,
+        })
+        return
+      }
     }
 
     this.baseStore.setState((d) => ({ ...d, isSubmitting: true }))
diff --git a/packages/form-core/tests/FormApi.spec.ts b/packages/form-core/tests/FormApi.spec.ts
index eccd2e544..5927aea19 100644
--- a/packages/form-core/tests/FormApi.spec.ts
+++ b/packages/form-core/tests/FormApi.spec.ts
@@ -1873,6 +1873,53 @@ describe('form api', () => {
     expect(formSubmit).toHaveBeenCalledOnce()
   })
 
+  it('should run field-level onBlur validators on re-submission to clear stale errors', async () => {
+    // Regression: stale onBlur errors could prevent re-submission because
+    // canSubmit became false and _handleSubmit returned early before running
+    // validateAllFields, which would have re-evaluated and cleared the error.
+    // See: https://github.com/TanStack/form/issues/2034
+    const onSubmit = vi.fn()
+    const onSubmitInvalid = vi.fn()
+
+    const form = new FormApi({
+      defaultValues: { type: 'PIN', pin: '' },
+      onSubmit,
+      onSubmitInvalid,
+    })
+    form.mount()
+
+    // PIN field with an onBlur validator that is only required when type === 'PIN'
+    const pinField = new FieldApi({
+      form,
+      name: 'pin',
+      validators: {
+        onBlur: ({ value }) =>
+          form.getFieldValue('type') === 'PIN' && !value
+            ? 'PIN is required'
+            : undefined,
+      },
+    })
+    pinField.mount()
+
+    // Simulate user touching and blurring the PIN field while type is 'PIN'
+    pinField.handleBlur()
+    expect(pinField.state.meta.errorMap.onBlur).toBe('PIN is required')
+
+    // First submit: form is invalid, onSubmitInvalid is called
+    await form.handleSubmit()
+    expect(onSubmitInvalid).toHaveBeenCalledTimes(1)
+    expect(onSubmit).not.toHaveBeenCalled()
+
+    // User switches type to 'Card' — PIN is no longer required
+    form.setFieldValue('type', 'Card')
+
+    // Second submit: the onBlur error is stale (PIN field still has it), but
+    // re-running validators on submit should clear it since type !== 'PIN'
+    await form.handleSubmit()
+    expect(onSubmit).toHaveBeenCalledTimes(1)
+    expect(onSubmitInvalid).toHaveBeenCalledTimes(1) // not called again
+  })
+
   it('should run all types of async validation on fields during submit', async () => {
     vi.useFakeTimers()
 

From 5145dec7c1eb814a3b920a4112d64ca791a907b5 Mon Sep 17 00:00:00 2001
From: restareaByWeezy <fjgkd7777@naver.com>
Date: Sat, 11 Apr 2026 19:58:41 +0900
Subject: [PATCH 2/2] chore: add changeset for #2034 fix

---
 .changeset/fix-stale-onblur-resubmit.md | 5 +++++
 1 file changed, 5 insertions(+)
 create mode 100644 .changeset/fix-stale-onblur-resubmit.md

diff --git a/.changeset/fix-stale-onblur-resubmit.md b/.changeset/fix-stale-onblur-resubmit.md
new file mode 100644
index 000000000..134c195b6
--- /dev/null
+++ b/.changeset/fix-stale-onblur-resubmit.md
@@ -0,0 +1,5 @@
+---
+'@tanstack/form-core': patch
+---
+
+fix(form-core): clear stale onBlur errors on re-submission