fix(types): update Route query type definition to support null values

- Updated TypeScript and Flow type definitions to properly handle null values in query parameters

- Added dedicated type tests to verify query parameter scenarios

Fixes #3566

Author: Yash Dayama

flow/declarations.js

@@ -1,3 +1,5 @@
+/* @flow */
+
 declare var document: Document;
 
 declare class RouteRegExp extends RegExp {
@@ -18,6 +20,8 @@ declare module 'path-to-regexp' {
 }
 
 declare type Dictionary<T> = { [key: string]: T }
+declare type QueryValue = string | null | Array<string | null>
+declare type QueryDictionary = { [key: string]: QueryValue }
 
 declare type NavigationGuard = (
   to: Route,
@@ -84,7 +88,7 @@ declare type Location = {
   name?: string;
   path?: string;
   hash?: string;
-  query?: Dictionary<string | null | Array<string | null>>;
+  query?: QueryDictionary;
   params?: Dictionary<string>;
   append?: boolean;
   replace?: boolean;
@@ -96,7 +100,7 @@ declare type Route = {
   path: string;
   name: ?string;
   hash: string;
-  query: Dictionary<string | null | Array<string | null>>;
+  query: QueryDictionary;
   params: Dictionary<string>;
   fullPath: string;
   matched: Array<RouteRecord>;

src/util/location.js

@@ -49,9 +49,9 @@ export function normalizeLocation (
     ? resolvePath(parsedPath.path, basePath, append || next.append)
     : basePath
 
-  const query = resolveQuery(
+  const query: QueryDictionary = resolveQuery(
     parsedPath.query,
-    next.query,
+    next.query || {},
     router && router.options.parseQuery
   )
 

src/util/query.js

@@ -27,9 +27,9 @@ export function decode (str: string) {
 
 export function resolveQuery (
   query: ?string,
-  extraQuery: Dictionary<string> = {},
+  extraQuery: QueryDictionary = {},
   _parseQuery: ?Function
-): Dictionary<string> {
+): QueryDictionary {
   const parse = _parseQuery || parseQuery
   let parsedQuery
   try {
@@ -49,7 +49,7 @@ export function resolveQuery (
 
 const castQueryParamValue = value => (value == null || typeof value === 'object' ? value : String(value))
 
-function parseQuery (query: string): Dictionary<string> {
+function parseQuery (query: string): QueryDictionary {
   const res = {}
 
   query = query.trim().replace(/^(\?|#|&)/, '')
@@ -75,7 +75,7 @@ function parseQuery (query: string): Dictionary<string> {
   return res
 }
 
-export function stringifyQuery (obj: Dictionary<string>): string {
+export function stringifyQuery (obj: QueryDictionary): string {
   const res = obj
     ? Object.keys(obj)
       .map(key => {

src/util/route.js

@@ -94,26 +94,24 @@ export function isSameRoute (a: Route, b: ?Route, onlyPath: ?boolean): boolean {
 }
 
 function isObjectEqual (a = {}, b = {}): boolean {
-  // handle null value #1566
   if (!a || !b) return a === b
-  const aKeys = Object.keys(a).sort()
-  const bKeys = Object.keys(b).sort()
-  if (aKeys.length !== bKeys.length) {
-    return false
+  if (Array.isArray(a) && Array.isArray(b)) {
+    return a.length === b.length && a.every((v, i) => String(v) === String(b[i]))
   }
-  return aKeys.every((key, i) => {
-    const aVal = a[key]
-    const bKey = bKeys[i]
-    if (bKey !== key) return false
-    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') {
+  if (a instanceof Object && b instanceof Object) {
+    const aKeys = Object.keys(a).sort()
+    const bKeys = Object.keys(b).sort()
+    if (aKeys.length !== bKeys.length) return false
+    return aKeys.every((key, i) => {
+      const aVal = a[key]
+      const bKey = bKeys[i]
+      if (bKey !== key) return false
+      const bVal = b[key]
+      if (aVal == null || bVal == null) return aVal === bVal
       return isObjectEqual(aVal, bVal)
-    }
-    return String(aVal) === String(bVal)
-  })
+    })
+  }
+  return String(a) === String(b)
 }
 
 export function isIncludedRoute (current: Route, target: Route): boolean {
@@ -126,11 +124,9 @@ export function isIncludedRoute (current: Route, target: Route): boolean {
   )
 }
 
-function queryIncludes (current: Dictionary<string>, target: Dictionary<string>): boolean {
+function queryIncludes (current: QueryDictionary, target: QueryDictionary): boolean {
   for (const key in target) {
-    if (!(key in current)) {
-      return false
-    }
+    if (!(key in current)) return false
   }
   return true
 }

types/test/index.ts

@@ -193,14 +193,23 @@ router.push({
     foo: 'foo'
   },
   query: {
-    bar: 'bar',
-    empty: null,
-    removed: undefined,
-    withEmpty: ['1', null],
-    foo: ['foo1', 'foo2']
+    bar: 'bar',                    
+    empty: null,                   
+    removed: undefined,            
+    withEmpty: ['1', null],       
+    foo: ['foo1', 'foo2'],      
+    queryWithoutValue: null,
+    mixedArray: [null, 'value']
   },
   hash: 'hash'
 })
+
+const routeQuery: Route['query'] = {
+  stringValue: 'test',             
+  nullValue: null,                 
+  arrayValue: ['test', null],      
+  emptyValue: null                 
+}
 router.replace({ name: 'home' })
 
 router.push(