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Author: 38elements

packages/test-utils/src/set-watchers-to-sync.js

@@ -27,6 +27,7 @@ export function setWatchersToSync (vm) {
 
   vm.$children.forEach(setWatchersToSync)
 
+  // preventing double registration
   if (!vm.$_vueTestUtils_updateInSetWatcherSync) {
     vm.$_vueTestUtils_updateInSetWatcherSync = vm._update
     vm._update = function (vnode, hydrating) {