From 5181d57bbdd1af0388c208fdf284ab33530298c6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pascal=20K=C3=BCsgen?= <pascalkuesgen@gmail.com>
Date: Wed, 22 Apr 2026 09:15:37 +0000
Subject: [PATCH] test: replaceFieldValue should clear onMount errors

---
 packages/form-core/tests/FormApi.spec.ts      | 86 +++++++++++++++++++
 .../tests/standardSchemaValidator.spec.ts     | 51 +++++++++++
 2 files changed, 137 insertions(+)

diff --git a/packages/form-core/tests/FormApi.spec.ts b/packages/form-core/tests/FormApi.spec.ts
index eccd2e544..4e75e9733 100644
--- a/packages/form-core/tests/FormApi.spec.ts
+++ b/packages/form-core/tests/FormApi.spec.ts
@@ -366,6 +366,92 @@ describe('form api', () => {
     expect(form.getFieldValue('names')).toStrictEqual(['one', 'two', 'three'])
   })
 
+  it("should clean onMount errors when replacing an array field's value", async () => {
+    const form = new FormApi({
+      defaultValues: {
+        people: [
+          {
+            firstName: '',
+            lastName: '',
+          },
+        ],
+      },
+      validators: {
+        onMount: ({ value }) => {
+          let fieldErrors: Record<string, string> = {}
+
+          value.people.map((x, index) => {
+            if (x.firstName.length < 3) {
+              fieldErrors[`people[${index}].firstName`] =
+                'First name is too short'
+            }
+
+            if (x.lastName.length < 3) {
+              fieldErrors[`people[${index}].lastName`] =
+                'Last name is too short'
+            }
+          })
+
+          if (Object.keys(fieldErrors).length > 0) {
+            return {
+              fields: { ...fieldErrors },
+            }
+          }
+
+          return fieldErrors
+        },
+        onChange: ({ value }) => {
+          let fieldErrors: Record<string, string> = {}
+
+          value.people.map((x, index) => {
+            if (x.firstName.length < 3) {
+              fieldErrors[`people[${index}].firstName`] =
+                'First name is too short'
+            }
+
+            if (x.lastName.length < 3) {
+              fieldErrors[`people[${index}].lastName`] =
+                'Last name is too short'
+            }
+          })
+
+          if (Object.keys(fieldErrors).length > 0) {
+            return {
+              fields: { ...fieldErrors },
+            }
+          }
+
+          return fieldErrors
+        },
+      },
+    })
+    form.mount()
+
+    // Since validation runs through the field, a field must be mounted for that array
+    new FieldApi({ form, name: 'people' }).mount()
+
+    await form.replaceFieldValue('people', 0, {
+      firstName: 'Chuck',
+      lastName: 'Norris',
+    })
+
+    expect(form.state.values).toStrictEqual({
+      people: [
+        {
+          firstName: 'Chuck',
+          lastName: 'Norris',
+        },
+      ],
+    })
+    expect.soft(form.state.fieldMetaBase['people']!.errorMap).toStrictEqual({})
+    expect
+      .soft(form.state.fieldMetaBase['people[0].firstName']!.errorMap)
+      .toStrictEqual({})
+    expect
+      .soft(form.state.fieldMetaBase['people[0].firstName']!.errorSourceMap)
+      .toStrictEqual({})
+  })
+
   it("should run onChange validation when inserting an array field's value", () => {
     const form = new FormApi({
       defaultValues: {
diff --git a/packages/form-core/tests/standardSchemaValidator.spec.ts b/packages/form-core/tests/standardSchemaValidator.spec.ts
index 463dac173..f1b668a4d 100644
--- a/packages/form-core/tests/standardSchemaValidator.spec.ts
+++ b/packages/form-core/tests/standardSchemaValidator.spec.ts
@@ -608,4 +608,55 @@ describe('standard schema validator', () => {
       ])
     })
   })
+
+  it("should clean onMount errors when replacing an array field's value", async () => {
+    const schema = z.object({
+      people: z.array(
+        z.object({
+          firstName: z.string().min(3),
+          lastName: z.string().min(3),
+        }),
+      ),
+    })
+
+    const form = new FormApi({
+      defaultValues: {
+        people: [
+          {
+            firstName: '',
+            lastName: '',
+          },
+        ],
+      },
+      validators: {
+        onMount: schema,
+        onChange: schema,
+      },
+    })
+    form.mount()
+
+    // Since validation runs through the field, a field must be mounted for that array
+    new FieldApi({ form, name: 'people' }).mount()
+
+    await form.replaceFieldValue('people', 0, {
+      firstName: 'Chuck',
+      lastName: 'Norris',
+    })
+
+    expect(form.state.values).toStrictEqual({
+      people: [
+        {
+          firstName: 'Chuck',
+          lastName: 'Norris',
+        },
+      ],
+    })
+    expect.soft(form.state.fieldMetaBase['people']!.errorMap).toStrictEqual({})
+    expect
+      .soft(form.state.fieldMetaBase['people[0].firstName']!.errorMap)
+      .toStrictEqual({})
+    expect
+      .soft(form.state.fieldMetaBase['people[0].firstName']!.errorSourceMap)
+      .toStrictEqual({})
+  })
 })