fix(router): properly check null and undefined in isSameRoute

Author: posva

src/util/query.js

@@ -38,7 +38,7 @@ export function resolveQuery (
   return parsedQuery
 }
 
-const castQueryParamValue = value => (value == null ? value : '' + value)
+const castQueryParamValue = value => (value == null ? value : String(value))
 
 function parseQuery (query: string): Dictionary<string> {
   const res = {}

src/util/route.js

@@ -104,6 +104,8 @@ function isObjectEqual (a = {}, b = {}): boolean {
   return aKeys.every(key => {
     const aVal = a[key]
     const bVal = b[key]
+    // query values can be null and undefined
+    if (aVal == null || bVal == null) return aVal === bVal
     // check nested equality
     if (typeof aVal === 'object' && typeof bVal === 'object') {
       return isObjectEqual(aVal, bVal)