Merge b5ae7a5 into 33c5836

Changelog.md

@@ -3,10 +3,10 @@
 ### next
 
 - **BREAKING CHANGES**
-  - typescript - `graphql` parameterized types streamlined for 
-a) full typing; and b) ease of use; and c) consistency.  New parameterized is: 
+  - typescript - `graphql` parameterized types streamlined for
+a) full typing; and b) ease of use; and c) consistency.  New parameterized is:
 `graphql<TProps,TData, TGraphQLVariables, TChildProps>` where none are required and full typing only requires the
-first three params (`TChildProps` can be derived). [#1402](https://github.com/apollographql/react-apollo/pull/1402) 
+first three params (`TChildProps` can be derived). [#1402](https://github.com/apollographql/react-apollo/pull/1402)
   - Remove deprecated `operationOptions.options.skip`, use `operationOptions.skip` instead
   - Rename type `ProviderProps` to `ApolloProviderProps` [#1467](https://github.com/apollographql/react-apollo/pull/1467)
   - Rename `getDataFromTree` type `QueryResult` to `QueryTreeResult` [#1467](https://github.com/apollographql/react-apollo/pull/1467)
@@ -33,6 +33,7 @@ first three params (`TChildProps` can be derived). [#1402](https://github.com/ap
   - Mutation test cleanup [#1480](https://github.com/apollographql/react-apollo/pull/1480)
   - Removed react-native from the test suite [#1451](https://github.com/apollographql/react-apollo/pull/1451)
   - Add `client` to `Query`'s `QueryResult` [#1488](https://github.com/apollographql/react-apollo/pull/1488)
+  - Disregard falsy elements when walking tree in SSR [#1495](https://github.com/apollographql/react-apollo/pull/1495)
 
 ### 2.0.4
 - rolled back on the lodash-es changes from

src/getDataFromTree.ts

@@ -37,7 +37,7 @@ export function walkTree<Cache>(
     return;
   }
 
-  if (element == null) return;
+  if (!element) return;
 
   const Component = element.type;
   // a stateless functional component or a class

test/server/getDataFromTree.test.tsx

@@ -41,6 +41,24 @@ describe('SSR', () => {
         expect(elementCount).toEqual(1);
       });
 
+      it('basic element trees with false', () => {
+        let elementCount = 0;
+        const rootElement = <div>{false}</div>;
+        walkTree(rootElement, {}, element => {
+          elementCount += 1;
+        });
+        expect(elementCount).toEqual(1);
+      });
+
+      it('basic element trees with empty string', () => {
+        let elementCount = 0;
+        const rootElement = <div>{''}</div>;
+        walkTree(rootElement, {}, element => {
+          elementCount += 1;
+        });
+        expect(elementCount).toEqual(1);
+      });
+
       it('basic element trees with arrays', () => {
         let elementCount = 0;
         const rootElement = [1, 2];
@@ -50,6 +68,15 @@ describe('SSR', () => {
         expect(elementCount).toEqual(2);
       });
 
+      it('basic element trees with false or null', () => {
+        let elementCount = 0;
+        const rootElement = [1, false, null, ''];
+        walkTree(rootElement, {}, element => {
+          elementCount += 1;
+        });
+        expect(elementCount).toEqual(1);
+      });
+
       it('functional stateless components', () => {
         let elementCount = 0;
         const MyComponent = ({ n }) => (