diff --git a/lib/__tests__/index-test.js b/lib/__tests__/index-test.js
index 4c684ef..de14b21 100644
--- a/lib/__tests__/index-test.js
+++ b/lib/__tests__/index-test.js
@@ -98,7 +98,7 @@ describe('props', () => {
     });
 
     describe('when role="button"', () => {
-      it('requires onKeyUp', () => {
+      it('requires onKeyDown', () => {
         expectWarning(assertions.props.onClick.BUTTON_ROLE_SPACE.msg, () => {
           <span onClick={k} role="button"/>;
         });
diff --git a/lib/assertions.js b/lib/assertions.js
index 3adede5..9d75695 100644
--- a/lib/assertions.js
+++ b/lib/assertions.js
@@ -68,8 +68,6 @@ exports.props = {
       }
     },
 
-    // onKeyUp is too late to cancel space's default behavior of scrolling the
-    // page.
     BUTTON_ROLE_SPACE: {
       msg: 'You have `role="button"` but did not define an `onKeyDown` handler. Add it, and have the "Space" key do the same thing as an `onClick` handler.',
       test (tagName, props, children) {
@@ -80,7 +78,7 @@ exports.props = {
     BUTTON_ROLE_ENTER: {
       msg: 'You have `role="button"` but did not define an `onKeyDown` handler. Add it, and have the "Enter" key do the same thing as an `onClick` handler.',
       test (tagName, props, children) {
-        return !(props.role === 'button' && props.onKeyDown);
+        return !(props.role === 'button' && !props.onKeyDown);
       }
     }