From c9273441e35e9177e5cb570a59267c6a1c8d2a83 Mon Sep 17 00:00:00 2001
From: weihaiyu <1600219867@qq.com>
Date: Tue, 21 Jul 2020 20:24:58 +0700
Subject: [PATCH] refactor(guards): optimize with one single for loop (#375)

* refactor(src): optimized with one single for loop

* refactor(src): optimized with one single for loop

* fix(src): The _RouteLocationBase define but never be used
---
 src/router.ts         | 22 +++++++++++++---------
 src/scrollBehavior.ts |  6 +-----
 2 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/src/router.ts b/src/router.ts
index c1d8d804..9447208d 100644
--- a/src/router.ts
+++ b/src/router.ts
@@ -985,15 +985,19 @@ function extractChangingRecords(
   const updatingRecords: RouteRecordNormalized[] = []
   const enteringRecords: RouteRecordNormalized[] = []
 
-  // TODO: could be optimized with one single for loop
-  for (const record of from.matched) {
-    if (to.matched.indexOf(record) < 0) leavingRecords.push(record)
-    else updatingRecords.push(record)
-  }
-
-  for (const record of to.matched) {
-    // the type doesn't matter because we are comparing per reference
-    if (from.matched.indexOf(record as any) < 0) enteringRecords.push(record)
+  const len = Math.max(from.matched.length, to.matched.length)
+  for (let i = 0; i < len; i++) {
+    const recordFrom = from.matched[i]
+    if (recordFrom) {
+      if (to.matched.indexOf(recordFrom) < 0) leavingRecords.push(recordFrom)
+      else updatingRecords.push(recordFrom)
+    }
+    const recordTo = to.matched[i]
+    if (recordTo) {
+      // the type doesn't matter because we are comparing per reference
+      if (from.matched.indexOf(recordTo as any) < 0)
+        enteringRecords.push(recordTo)
+    }
   }
 
   return [leavingRecords, updatingRecords, enteringRecords]
diff --git a/src/scrollBehavior.ts b/src/scrollBehavior.ts
index 066b2f87..4d955cec 100644
--- a/src/scrollBehavior.ts
+++ b/src/scrollBehavior.ts
@@ -1,8 +1,4 @@
-import {
-  RouteLocationNormalized,
-  RouteLocationNormalizedLoaded,
-  _RouteLocationBase,
-} from './types'
+import { RouteLocationNormalized, RouteLocationNormalizedLoaded } from './types'
 import { warn } from './warning'
 
 // we use types instead of interfaces to make it work with HistoryStateValue type
-- 
2.47.3