@@ -0,0 +1,17 @@
+---
+'@object-ui/components': patch
+'@object-ui/i18n': patch
+---
+
+feat(components): the edit form names the fields a visible update action would require, before the action is pressed
+
+Clause-②: yes (widening: `@object-ui/i18n` gains the `form.requiredForAction` key in all ten locales; no accept set moves)
+Metadata-protocol: none
+
+A declarative update action (`operation: 'update'` with a static `patch`) writes its patch over the record, and the server runs the object's `requiredWhen` rules over the result. The edit form judged the record as it stands, so a field that only the action makes required showed nothing, and the first press was refused. In the showcase, "Issued On" on a draft invoice is required once `status` is `sent`, and "Submit for Sign-off" sets `status: 'sent'`.
+
+The form renderer now reads the object's declared actions on an edit form, through the data source it already has. For each update action that is placed, not switched off, permitted and visible for the record, it evaluates each field's `requiredWhen` over the record merged with the patch. An empty field that comes out required shows "Required to run “Submit for Sign-off”." under the control, inside the description the control's `aria-describedby` names.
+
+- It is a heads-up only. Save is not blocked, and the field is not marked required for Save. The server's refusal stays the source of truth.
+- Actions that collect `params`, and actions whose write is not a static `patch`, are skipped, because what they write is not known before they run.
+- A create form reads and marks nothing.
@@ -0,0 +1,254 @@
+/**
+ * ObjectUI
+ * Copyright (c) 2024-present ObjectStack Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+/**
+ * objectstack#28382 — an EDIT form names the fields a visible update action's
+ * static `patch` would make required, before the action is pressed.
+ *
+ * The reported case, from the showcase: a draft invoice's "Issued On" carries
+ * `requiredWhen: record.status in ['sent', 'paid']`, and "Submit for Sign-off"
+ * is `operation: 'update'` + `patch: { status: 'sent' }`. The server runs the
+ * rule over the record the patch leaves, so the first press was refused with
+ * "Issued On is required", while the form — judging `status: 'draft'` — drew
+ * nothing on the field.
+ *
+ * The door is the real `form` renderer with a data source in
+ * `SchemaRendererContext`, which is where it reads the object's actions from.
+ */
+
+import { describe, it, expect, beforeEach, afterEach, vi } from 'vitest';
+import React from 'react';
+import { render, screen, fireEvent, waitFor, cleanup } from '@testing-library/react';
+import { ComponentRegistry } from '@object-ui/core';
+import { SchemaRendererContext } from '@object-ui/react';
+// Module scope, not `beforeAll` — see object-ui/no-dynamic-import-in-test-hook.
+import '../../../renderers';
+import { patchingUpdateActions } from '../actionRequirements';
+
+beforeEach(() => {
+  if (!(Element.prototype as any).scrollIntoView) {
+    (Element.prototype as any).scrollIntoView = () => {};
+  }
+});
+
+afterEach(() => {
+  cleanup();
+  vi.restoreAllMocks();
+});
+
+const SUBMIT_SIGNOFF = {
+  name: 'showcase_submit_signoff',
+  label: 'Submit for Sign-off',
+  operation: 'update',
+  patch: { status: 'sent' },
+  visible: { dialect: 'cel', source: "has(record.status) && record.status != 'sent'" },
+  locations: ['list_item', 'record_header'],
+};
+
+const FIELDS = [
+  { name: 'name', label: 'Invoice Number', type: 'input' },
+  { name: 'status', label: 'Status', type: 'input' },
+  {
+    name: 'issued_on',
+    label: 'Issued On',
+    type: 'input',
+    requiredWhen: { dialect: 'cel', source: "record.status in ['sent', 'paid']" },
+  },
+];
+
+const DRAFT = { id: 'inv1', name: 'INV-1004', status: 'draft', issued_on: null };
+
+const NOTE = 'Required to run “Submit for Sign-off”.';
+
+function renderInvoiceForm(opts: {
+  actions?: unknown[];
+  record?: Record<string, unknown>;
+  edit?: boolean;
+  onSubmit?: (data: any) => unknown;
+}) {
+  const record = opts.record ?? DRAFT;
+  const getObjectSchema = vi.fn(async () => ({ name: 'showcase_invoice', actions: opts.actions ?? [SUBMIT_SIGNOFF] }));
+  const Form = ComponentRegistry.get('form')!;
+  const view = render(
+    <SchemaRendererContext.Provider value={{ dataSource: { getObjectSchema } } as any}>
+      <Form
+        schema={{
+          type: 'form',
+          objectName: 'showcase_invoice',
+          showSubmit: true,
+          showCancel: false,
+          submitLabel: 'Save',
+          defaultValues: record,
+          ...(opts.edit === false ? {} : { previousValues: record }),
+          fields: FIELDS,
+          onSubmit: opts.onSubmit ?? (() => undefined),
+        }}
+      />
+    </SchemaRendererContext.Provider>,
+  );
+  return { ...view, getObjectSchema };
+}
+
+const issuedOnInput = () => screen.getByLabelText(/Issued On/) as HTMLInputElement;
+const noteOnIssuedOn = () =>
+  document.querySelector('[data-testid="field:showcase_invoice.issued_on"] [data-required-for-action="true"]');
+
+describe('form renderer — fields an update action would require (objectstack#28382)', () => {
+  it('notes the action under the empty field its patch makes required, on an edit form', async () => {
+    const { getObjectSchema } = renderInvoiceForm({});
+
+    await waitFor(() => expect(noteOnIssuedOn()?.textContent).toBe(NOTE));
+    expect(getObjectSchema).toHaveBeenCalledWith('showcase_invoice');
+    // It is announced with the field: the note sits inside the description the
+    // control's `aria-describedby` names.
+    const describedBy = issuedOnInput().getAttribute('aria-describedby') ?? '';
+    const described = describedBy
+      .split(/\s+/)
+      .map((id) => document.getElementById(id)?.textContent ?? '')
+      .join(' ');
+    expect(described).toContain(NOTE);
+    // Required for the action, not for Save: no asterisk state on the control.
+    expect(issuedOnInput().getAttribute('aria-required')).toBeNull();
+    // Only the field the rule names: the other fields carry no note.
+    expect(document.querySelectorAll('[data-required-for-action="true"]')).toHaveLength(1);
+  });
+
+  it('never blocks Save: the record is written with the field still empty', async () => {
+    const onSubmit = vi.fn();
+    renderInvoiceForm({ onSubmit });
+    await waitFor(() => expect(noteOnIssuedOn()).not.toBeNull());
+
+    fireEvent.click(screen.getByRole('button', { name: 'Save' }));
+
+    await waitFor(() => expect(onSubmit).toHaveBeenCalledTimes(1));
+    expect(onSubmit.mock.calls[0][0]).toMatchObject({ status: 'draft' });
+  });
+
+  it('drops the note once the field holds a value', async () => {
+    renderInvoiceForm({});
+    await waitFor(() => expect(noteOnIssuedOn()).not.toBeNull());
+
+    fireEvent.change(issuedOnInput(), { target: { value: '2026-10-31' } });
+
+    await waitFor(() => expect(noteOnIssuedOn()).toBeNull());
+  });
+
+  it('gives way to the asterisk when the record as it stands already requires the field', async () => {
+    renderInvoiceForm({});
+    await waitFor(() => expect(noteOnIssuedOn()).not.toBeNull());
+
+    // Typing a status the rule names makes the field required for Save itself.
+    // The action is still visible (`paid` is not `sent`) and would still
+    // require it, but the asterisk already says so: no second note.
+    fireEvent.change(screen.getByLabelText(/Status/), { target: { value: 'paid' } });
+
+    await waitFor(() => expect(issuedOnInput().getAttribute('aria-required')).toBe('true'));
+    expect(noteOnIssuedOn()).toBeNull();
+  });
+
+  it('does not read or note anything on a create form', async () => {
+    const { getObjectSchema } = renderInvoiceForm({ edit: false });
+    // Let any effect settle before reading the absence.
+    await new Promise((r) => setTimeout(r, 20));
+    expect(getObjectSchema).not.toHaveBeenCalled();
+    expect(noteOnIssuedOn()).toBeNull();
+  });
+
+  it('makes no read when no field declares a `requiredWhen`', async () => {
+    const getObjectSchema = vi.fn(async () => ({ name: 'showcase_invoice', actions: [SUBMIT_SIGNOFF] }));
+    const Form = ComponentRegistry.get('form')!;
+    render(
+      <SchemaRendererContext.Provider value={{ dataSource: { getObjectSchema } } as any}>
+        <Form
+          schema={{
+            type: 'form',
+            objectName: 'showcase_invoice',
+            defaultValues: DRAFT,
+            previousValues: DRAFT,
+            fields: FIELDS.map(({ requiredWhen: _rule, ...rest }: any) => rest),
+          }}
+        />
+      </SchemaRendererContext.Provider>,
+    );
+    // Let any effect settle before reading the absence.
+    await new Promise((r) => setTimeout(r, 20));
+    expect(getObjectSchema).not.toHaveBeenCalled();
+    expect(noteOnIssuedOn()).toBeNull();
+  });
+
+  it('skips an action whose `visible` does not hold over the record', async () => {
+    const { getObjectSchema } = renderInvoiceForm({
+      actions: [{ ...SUBMIT_SIGNOFF, visible: { dialect: 'cel', source: "record.status == 'approved'" } }],
+    });
+    await waitFor(() => expect(getObjectSchema).toHaveBeenCalled());
+    await new Promise((r) => setTimeout(r, 20));
+    expect(noteOnIssuedOn()).toBeNull();
+  });
+
+  it('skips an action that collects params', async () => {
+    const { getObjectSchema } = renderInvoiceForm({
+      actions: [{ ...SUBMIT_SIGNOFF, params: [{ name: 'note', type: 'text' }] }],
+    });
+    await waitFor(() => expect(getObjectSchema).toHaveBeenCalled());
+    await new Promise((r) => setTimeout(r, 20));
+    expect(noteOnIssuedOn()).toBeNull();
+  });
+
+  it('names every action that would require the field, one line each', async () => {
+    renderInvoiceForm({
+      actions: [
+        SUBMIT_SIGNOFF,
+        { name: 'mark_paid', label: 'Mark Paid', operation: 'update', patch: { status: 'paid' }, locations: ['record_header'] },
+        // Writes a status the rule does not name: no line.
+        { name: 'void_it', label: 'Void', operation: 'update', patch: { status: 'void' }, locations: ['record_header'] },
+      ],
+    });
+
+    await waitFor(() =>
+      expect(
+        Array.from(document.querySelectorAll('[data-required-for-action="true"]')).map((n) => n.textContent),
+      ).toEqual([NOTE, 'Required to run “Mark Paid”.']),
+    );
+  });
+});
+
+describe('patchingUpdateActions — which declared actions write only their patch', () => {
+  it('keeps a placed `operation: update` action with a static patch and no params', () => {
+    expect(patchingUpdateActions([SUBMIT_SIGNOFF]).map((a) => [a.name, a.label, a.patch])).toEqual([
+      ['showcase_submit_signoff', 'Submit for Sign-off', { status: 'sent' }],
+    ]);
+  });
+
+  it('leaves out every action whose write is not known before it runs', () => {
+    expect(
+      patchingUpdateActions([
+        { ...SUBMIT_SIGNOFF, name: 'a', operation: undefined },
+        { ...SUBMIT_SIGNOFF, name: 'b', type: 'api', operation: undefined, patch: undefined, target: '/x' },
+        { ...SUBMIT_SIGNOFF, name: 'c', patch: {} },
+        { ...SUBMIT_SIGNOFF, name: 'd', params: [{ name: 'p' }] },
+        { ...SUBMIT_SIGNOFF, name: 'e', locations: [] },
+        { ...SUBMIT_SIGNOFF, name: 'f', locations: undefined },
+        null,
+        'showcase_submit_signoff',
+      ]),
+    ).toEqual([]);
+  });
+
+  it('keeps an empty params list, falls back to the name for a label, and de-duplicates by name', () => {
+    const found = patchingUpdateActions([
+      { ...SUBMIT_SIGNOFF, params: [], label: undefined },
+      SUBMIT_SIGNOFF,
+    ]);
+    expect(found.map((a) => a.label)).toEqual(['showcase_submit_signoff']);
+  });
+
+  it('answers none for anything that is not a list', () => {
+    expect(patchingUpdateActions(undefined)).toEqual([]);
+    expect(patchingUpdateActions({ actions: [SUBMIT_SIGNOFF] })).toEqual([]);
+  });
+});