Fixes bug where children were continuously traversed despite a visitor result indicating the desire to stop traversal.

Author: ctrlplusb

src/__tests__/index.test.js

@@ -90,6 +90,25 @@ describe('reactTreeWalker', () => {
     })
   })
 
+  it('promise based visitor stops resolving', () => {
+    const tree = createTree(true)
+    const actual = []
+    // eslint-disable-next-line no-unused-vars
+    const visitor = (element, instance, context) => {
+      if (instance && typeof instance.getSomething === 'function') {
+        return instance.getSomething().then(something => {
+          actual.push(something)
+          return something !== 4
+        })
+      }
+      return true
+    }
+    return reactTreeWalker(tree, visitor).then(() => {
+      const expected = [1, 2, 4, 3]
+      expect(actual).toEqual(expected)
+    })
+  })
+
   it('componentWillMount & setState', () => {
     let actual = {}
 
@@ -101,7 +120,9 @@ describe('reactTreeWalker', () => {
 
       componentWillMount() {
         this.setState({ foo: 'bar' })
-        this.setState((state, props) => ({ other: `I am ${props.value} ${state.foo}` }))
+        this.setState((state, props) => ({
+          other: `I am ${props.value} ${state.foo}`,
+        }))
       }
 
       render() {

src/index.js

@@ -66,13 +66,8 @@ export default function reactTreeWalker(
   options = defaultOptions,
 ) {
   return new Promise(resolve => {
-    const doVisit = (getChildren, visitorResult, childContext) => {
-      const doTraverse = shouldContinue => {
-        if (!shouldContinue) {
-          // We recieved a false, which indicates a desire to stop traversal.
-          resolve()
-        }
-
+    const doVisit = (getChildren, visitResult, childContext) => {
+      const visitChildren = () => {
         const child = ensureChild(getChildren())
         const theChildContext =
           typeof childContext === 'function' ? childContext() : childContext
@@ -97,25 +92,34 @@ export default function reactTreeWalker(
         }
       }
 
-      if (visitorResult === false) {
+      if (visitResult === false) {
         // Visitor returned false, indicating a desire to not traverse.
         resolve()
-      } else if (isPromise(visitorResult)) {
+      } else if (isPromise(visitResult)) {
         // We need to execute the result and pass it's result through to our
         // continuer.
-        visitorResult.then(doTraverse).catch(e => {
-          console.log(
-            'Error occurred in Promise based visitor result provided to react-tree-walker.',
-          )
-          if (e) {
-            console.log(e)
-            if (e.stack) {
-              console.log(e.stack)
+        visitResult
+          .then(promiseResult => {
+            if (promiseResult === false) {
+              resolve()
+            } else {
+              visitChildren()
             }
-          }
-        })
+          })
+          .catch(e => {
+            console.log(
+              'Error occurred in Promise based visitor provided to react-tree-walker.',
+            )
+            if (e) {
+              console.log(e)
+              if (e.stack) {
+                console.log(e.stack)
+              }
+            }
+          })
       } else {
-        doTraverse(true)
+        // Visitor returned true, indicating a desire to continue traversing.
+        visitChildren()
       }
     }