Correct typing/nullability for react_dom.dart's findDomNode and render

Author: greglittlefield-wf

lib/react_client/react_interop.dart

@@ -274,8 +274,8 @@ ReactComponentFactoryProxy memo2(ReactComponentFactoryProxy factory,
 }
 
 abstract class ReactDom {
-  static Element findDOMNode(object) => ReactDOM.findDOMNode(object);
-  static ReactComponent render(ReactElement component, Element element) => ReactDOM.render(component, element);
+  static Element? findDOMNode(dynamic object) => ReactDOM.findDOMNode(object);
+  static ReactComponent render(dynamic component, Element element) => ReactDOM.render(component, element);
   static bool unmountComponentAtNode(Element element) => ReactDOM.unmountComponentAtNode(element);
 
   /// Returns a a portal that renders [children] into a [container].

lib/src/react_client/dart2_interop_workaround_bindings.dart

@@ -8,8 +8,8 @@ import 'package:react/react_client/react_interop.dart';
 
 @JS()
 abstract class ReactDOM {
-  external static Element findDOMNode(object);
-  external static ReactComponent render(ReactElement component, Element element);
+  external static Element? findDOMNode(dynamic object);
+  external static ReactComponent render(dynamic component, Element element);
   external static bool unmountComponentAtNode(Element element);
   external static ReactPortal createPortal(dynamic children, Element container);
 }

test/lifecycle_test.dart

@@ -480,7 +480,7 @@ main() {
         final mountNode = DivElement();
         final renderedInstance = react_dom.render(components2.SetStateTest({}), mountNode);
         final component = getDartComponent<LifecycleTestHelper>(renderedInstance);
-        final renderedNode = findDomNode(renderedInstance);
+        final renderedNode = findDomNode(renderedInstance)!;
         LifecycleTestHelper.staticLifecycleCalls.clear();
         component.setState({'shouldThrow': true});
 
@@ -1518,7 +1518,7 @@ void sharedLifecycleTests<T extends react.Component>({
       test('when shouldComponentUpdate returns false', () {
         final mountNode = DivElement();
         final renderedInstance = react_dom.render(SetStateTest({'shouldUpdate': false}), mountNode);
-        final renderedNode = findDomNode(renderedInstance);
+        final renderedNode = findDomNode(renderedInstance)!;
         final component = getDartComponent<LifecycleTestHelper>(renderedInstance);
 
         react_test_utils.Simulate.click(renderedNode.children.first);
@@ -1541,7 +1541,7 @@ void sharedLifecycleTests<T extends react.Component>({
       test('when shouldComponentUpdate returns true', () {
         final mountNode = DivElement();
         final renderedInstance = react_dom.render(SetStateTest({}), mountNode);
-        final renderedNode = findDomNode(renderedInstance);
+        final renderedNode = findDomNode(renderedInstance)!;
         final component = getDartComponent<LifecycleTestHelper>(renderedInstance);
 
         react_test_utils.Simulate.click(renderedNode.children.first);

test/react_test_utils_test.dart

@@ -66,7 +66,7 @@ void testUtils({
 
     setUp(() {
       component = renderIntoDocument(eventComponent({})) as Object;
-      domNode = findDomNode(component);
+      domNode = findDomNode(component)!;
       expect(domNode.text, equals(''));
     });
 
@@ -350,12 +350,12 @@ void testUtils({
 
     expect(divElements.length, equals(3));
     // First div should be the parent div created by renderIntoDocument()
-    expect(findDomNode(divElements[0]).text, equals('A headerFirst divSecond div'));
-    expect(findDomNode(divElements[1]).text, equals('First div'));
-    expect(findDomNode(divElements[2]).text, equals('Second div'));
+    expect(findDomNode(divElements[0])!.text, equals('A headerFirst divSecond div'));
+    expect(findDomNode(divElements[1])!.text, equals('First div'));
+    expect(findDomNode(divElements[2])!.text, equals('Second div'));
     expect(h1Elements.length, equals(1));
-    expect(findDomNode(h1Elements[0]).text, equals('A header'));
+    expect(findDomNode(h1Elements[0])!.text, equals('A header'));
     expect(spanElements.length, equals(1));
-    expect(findDomNode(spanElements[0]).text, equals(''));
+    expect(findDomNode(spanElements[0])!.text, equals(''));
   });
 }

test/util.dart

@@ -49,7 +49,7 @@ ReactComponent render(ReactElement reactElement) {
 }
 
 // Same as the public API but with tightened types to help fix implicit casts
-Element findDomNode(dynamic component) => react_dom.findDOMNode(component) as Element;
+Element? findDomNode(dynamic component) => react_dom.findDOMNode(component) as Element?;
 
 /// Returns a new [Map.unmodifiable] with all argument maps merged in.
 Map unmodifiableMap([Map? map1, Map? map2, Map? map3, Map? map4]) {