diff --git a/src/renderers/shared/fiber/ReactChildFiber.js b/src/renderers/shared/fiber/ReactChildFiber.js index 4320df60ea..c48371a9c7 100644 --- a/src/renderers/shared/fiber/ReactChildFiber.js +++ b/src/renderers/shared/fiber/ReactChildFiber.js @@ -806,15 +806,13 @@ function ChildReconciler(shouldClone, shouldTrackSideEffects) { // First, validate keys. // We'll get a different iterator later for the main pass. const newChildren = iteratorFn.call(newChildrenIterable); - invariant( - newChildren != null, - 'An iterable object provided no iterator.' - ); - let knownKeys = null; - let step = newChildren.next(); - for (; !step.done; step = newChildren.next()) { - const child = step.value; - knownKeys = warnOnDuplicateKey(child, knownKeys); + if (newChildren) { + let knownKeys = null; + let step = newChildren.next(); + for (; !step.done; step = newChildren.next()) { + const child = step.value; + knownKeys = warnOnDuplicateKey(child, knownKeys); + } } }