Feat: Form attribute of button with type submit

packages/@react-spectrum/button/test/Button.test.js

@@ -363,5 +363,19 @@ describe('Button', function () {
     expect(button).not.toHaveAttribute('href');
   });
 
+  it('associates button with form with form id', () => {
+    let {getByRole} = render(
+      <Provider theme={defaultTheme}>
+        <Form id="testForm">
+          <Checkbox>An Input</Checkbox>
+        </Form>
+        <Button form="testForm">Submit</Button>
+      </Provider>
+    );
+
+    let button = getByRole('button');
+    expect(button).toHaveAttribute('form', 'testForm');
+  });
+
   // 'implicit submission' can't be tested https://github.com/testing-library/react-testing-library/issues/487
 });

packages/@react-types/button/src/index.d.ts

@@ -95,7 +95,13 @@ export interface SpectrumButtonProps<T extends ElementType = 'button'> extends A
    * Whether the button should be displayed with a quiet style.
    * @deprecated
    */
-  isQuiet?: boolean
+  isQuiet?: boolean, 
+  /**
+   * The `<form>` element to associate the button with.
+   * The value of this attribute must be the id of a `<form>` in the same document.
+   * See [form attribute](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/button#form).
+   */
+  form?: string
 }
 
 export interface SpectrumActionButtonProps extends AriaBaseButtonProps, Omit<ButtonProps, 'onClick'>, StyleProps {