Avoid setting empty value on reset & submit inputs

packages/react-dom/src/__tests__/ReactDOMInput-test.js

@@ -752,15 +752,40 @@ describe('ReactDOMInput', () => {
 
   it('should not set a value for submit buttons unnecessarily', () => {
     const stub = <input type="submit" />;
-    const node = ReactDOM.render(stub, container);
+    ReactDOM.render(stub, container);
+    const node = container.firstChild;
 
     // The value shouldn't be '', or else the button will have no text; it
     // should have the default "Submit" or "Submit Query" label. Most browsers
     // report this as not having a `value` attribute at all; IE reports it as
     // the actual label that the user sees.
-    expect(
-      !node.hasAttribute('value') || node.getAttribute('value').length > 0,
-    ).toBe(true);
+    expect(node.hasAttribute('value')).toBe(false);
+  });
+
+  it('should not set a value for submit buttons when undefined is supplied', () => {
+    let stub = <input type="submit" onChange={emptyFunction} />;
+    ReactDOM.render(stub, container);
+    stub = <input type="submit" value={undefined} onChange={emptyFunction} />;
+    ReactDOM.render(stub, container);
+    const node = container.firstChild;
+
+    expect(node.hasAttribute('value')).toBe(false);
+  });
+
+  it('should set a value to a submit input', () => {
+    let stub = <input type="submit" value="banana" />;
+    ReactDOM.render(stub, container);
+    const node = container.firstChild;
+
+    expect(node.getAttribute('value')).toBe('banana');
+  });
+
+  it('should set an empty string value on a submit input', () => {
+    let stub = <input type="submit" value="" />;
+    ReactDOM.render(stub, container);
+    const node = container.firstChild;
+
+    expect(node.getAttribute('value')).toBe('');
   });
 
   it('should control radio buttons', () => {

packages/react-dom/src/client/ReactDOMFiberInput.js

@@ -182,6 +182,14 @@ export function updateWrapper(element: Element, props: Object) {
     } else if (node.value !== '' + value) {
       node.value = '' + value;
     }
+  } else if (
+    (props.type === 'submit' || props.type === 'reset') &&
+    (value === null || value === undefined)
+  ) {
+    // Submit/reset inputs need the attribute removed completely to avoid
+    // blank-text buttons.
+    node.removeAttribute('value');
+    return;
   }
 
   if (props.hasOwnProperty('value')) {
@@ -203,6 +211,16 @@ export function postMountWrapper(
   const node = ((element: any): InputWithWrapperState);
 
   if (props.hasOwnProperty('value') || props.hasOwnProperty('defaultValue')) {
+    // Submit or reset inputs should not have their value overridden
+    // with a null or undefined value, or else this will result in a button with
+    // no text, ignoring the browser-default "Submit", etc.
+    if (
+      (props.value === undefined || props.value === null) &&
+      (props.type === 'submit' || props.type === 'reset')
+    ) {
+      return;
+    }
+
     const initialValue = '' + node._wrapperState.initialValue;
     const currentValue = node.value;