Skip special nodes when reading TestInstance.parent (#12813)

Author: gaearon

src/ReactTestRenderer.js

@@ -245,10 +245,14 @@ class ReactTestInstance {
   }
 
   get parent(): ?ReactTestInstance {
-    const parent = this._fiber.return;
-    return parent === null || parent.tag === HostRoot
-      ? null
-      : wrapFiber(parent);
+    let parent = this._fiber.return;
+    while (parent !== null) {
+      if (validWrapperTypes.has(parent.tag)) {
+        return wrapFiber(parent);
+      }
+      parent = parent.return;
+    }
+    return null;
   }
 
   get children(): Array<ReactTestInstance | string> {
@@ -262,30 +266,12 @@ class ReactTestInstance {
     node = node.child;
     outer: while (true) {
       let descend = false;
-      switch (node.tag) {
-        case FunctionalComponent:
-        case ClassComponent:
-        case HostComponent:
-        case ForwardRef:
-          children.push(wrapFiber(node));
-          break;
-        case HostText:
-          children.push('' + node.memoizedProps);
-          break;
-        case Fragment:
-        case ContextProvider:
-        case ContextConsumer:
-        case Mode:
-        case Profiler:
-          descend = true;
-          break;
-        default:
-          invariant(
-            false,
-            'Unsupported component type %s in test renderer. ' +
-              'This is probably a bug in React.',
-            node.tag,
-          );
+      if (validWrapperTypes.has(node.tag)) {
+        children.push(wrapFiber(node));
+      } else if (node.tag === HostText) {
+        children.push('' + node.memoizedProps);
+      } else {
+        descend = true;
       }
       if (descend && node.child !== null) {
         node.child.return = node;

src/__tests__/ReactTestRendererTraversal-test.js

@@ -12,6 +12,7 @@
 
 const React = require('react');
 let ReactTestRenderer;
+let Context;
 
 const RCTView = 'RCTView';
 const View = props => <RCTView {...props} />;
@@ -20,6 +21,7 @@ describe('ReactTestRendererTraversal', () => {
   beforeEach(() => {
     jest.resetModules();
     ReactTestRenderer = require('react-test-renderer');
+    Context = React.createContext(null);
   });
 
   class Example extends React.Component {
@@ -40,6 +42,17 @@ describe('ReactTestRendererTraversal', () => {
             <React.unstable_Profiler id="test" onRender={() => {}}>
               <ExampleForwardRef qux="qux" />
             </React.unstable_Profiler>
+            <React.Fragment>
+              <React.Fragment>
+                <Context.Provider value={null}>
+                  <Context.Consumer>
+                    {() => <View nested={true} />}
+                  </Context.Consumer>
+                </Context.Provider>
+              </React.Fragment>
+              <View nested={true} />
+              <View nested={true} />
+            </React.Fragment>
           </View>
         </View>
       );
@@ -61,7 +74,7 @@ describe('ReactTestRendererTraversal', () => {
 
     // assert .props, .type and .parent attributes
     const foo = render.root.find(hasFooProp);
-    expect(foo.props.children).toHaveLength(8);
+    expect(foo.props.children).toHaveLength(9);
     expect(foo.type).toBe(View);
     expect(render.root.parent).toBe(null);
     expect(foo.children[0].parent).toBe(foo);
@@ -76,13 +89,15 @@ describe('ReactTestRendererTraversal', () => {
     const hasNullProp = node => node.props.hasOwnProperty('null');
     const hasVoidProp = node => node.props.hasOwnProperty('void');
     const hasItselfProp = node => node.props.hasOwnProperty('itself');
+    const hasNestedProp = node => node.props.hasOwnProperty('nested');
 
     expect(() => render.root.find(hasFooProp)).not.toThrow(); // 1 match
     expect(() => render.root.find(hasBarProp)).toThrow(); // >1 matches
     expect(() => render.root.find(hasBazProp)).toThrow(); // >1 matches
     expect(() => render.root.find(hasBingProp)).not.toThrow(); // 1 match
     expect(() => render.root.find(hasNullProp)).not.toThrow(); // 1 match
     expect(() => render.root.find(hasVoidProp)).toThrow(); // 0 matches
+    expect(() => render.root.find(hasNestedProp)).toThrow(); // >1 matches
 
     // same assertion as .find(), but confirm length
     expect(render.root.findAll(hasFooProp, {deep: false})).toHaveLength(1);
@@ -91,6 +106,7 @@ describe('ReactTestRendererTraversal', () => {
     expect(render.root.findAll(hasBingProp, {deep: false})).toHaveLength(1);
     expect(render.root.findAll(hasNullProp, {deep: false})).toHaveLength(1);
     expect(render.root.findAll(hasVoidProp, {deep: false})).toHaveLength(0);
+    expect(render.root.findAll(hasNestedProp, {deep: false})).toHaveLength(3);
 
     // note: with {deep: true}, .findAll() will continue to
     //       search children, even after finding a match
@@ -100,6 +116,7 @@ describe('ReactTestRendererTraversal', () => {
     expect(render.root.findAll(hasBingProp)).toHaveLength(1); // no spread
     expect(render.root.findAll(hasNullProp)).toHaveLength(1); // no spread
     expect(render.root.findAll(hasVoidProp)).toHaveLength(0);
+    expect(render.root.findAll(hasNestedProp, {deep: false})).toHaveLength(3);
 
     const bing = render.root.find(hasBingProp);
     expect(bing.find(hasBarProp)).toBe(bing);
@@ -130,7 +147,7 @@ describe('ReactTestRendererTraversal', () => {
 
     expect(render.root.findAllByType(ExampleFn)).toHaveLength(1);
     expect(render.root.findAllByType(View, {deep: false})).toHaveLength(1);
-    expect(render.root.findAllByType(View)).toHaveLength(8);
+    expect(render.root.findAllByType(View)).toHaveLength(11);
     expect(render.root.findAllByType(ExampleNull)).toHaveLength(2);
     expect(render.root.findAllByType(ExampleForwardRef)).toHaveLength(1);
 
@@ -164,4 +181,22 @@ describe('ReactTestRendererTraversal', () => {
     expect(render.root.findAllByProps({baz})).toHaveLength(4);
     expect(render.root.findAllByProps({qux})).toHaveLength(3);
   });
+
+  it('skips special nodes', () => {
+    const render = ReactTestRenderer.create(<Example />);
+    expect(render.root.findAllByType(React.Fragment)).toHaveLength(0);
+    expect(render.root.findAllByType(Context.Consumer)).toHaveLength(0);
+    expect(render.root.findAllByType(Context.Provider)).toHaveLength(0);
+
+    const expectedParent = render.root.findByProps({foo: 'foo'}, {deep: false})
+      .children[0];
+    const nestedViews = render.root.findAllByProps(
+      {nested: true},
+      {deep: false},
+    );
+    expect(nestedViews.length).toBe(3);
+    expect(nestedViews[0].parent).toBe(expectedParent);
+    expect(nestedViews[1].parent).toBe(expectedParent);
+    expect(nestedViews[2].parent).toBe(expectedParent);
+  });
 });