[cookie_manager] Fix set-cookie multi-value parsing (#1675)

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- [x] I have read the
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- [x] I have searched for a similar pull request in the
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### Additional context and info (if any)

Fix #1674

plugins/cookie_manager/CHANGELOG.md

@@ -1,8 +1,9 @@
 # CHANGELOG
 
-# 2.1.1
+## 2.1.1
 
 * Fix #1651
+* Fix #1674
 
 ## 2.1.0
 

plugins/cookie_manager/lib/src/cookie_mgr.dart

@@ -8,6 +8,17 @@ const _kIsWeb = bool.hasEnvironment('dart.library.js_util')
     ? bool.fromEnvironment('dart.library.js_util')
     : identical(0, 0.0);
 
+/// - `(?<=)` is a positive lookbehind assertion that matches a comma (",")
+/// only if it's preceded by a specific pattern. In this case, the lookbehind
+/// assertion is empty, which means it matches any comma that's preceded by any character.
+/// - `(,)` captures the comma as a group.
+/// - `(?=[^;]+?=)` is a positive lookahead assertion that matches a comma only
+/// if it's followed by a specific pattern. In this case, it matches any comma
+/// that's followed by one or more characters that are not semicolons (";") and
+/// then an equals sign ("="). This ensures that the comma is not part of a cookie
+/// attribute like "expires=Sun, 19 Feb 3000 01:43:15 GMT", which could also contain commas.
+final _setCookieReg = RegExp('(?<=)(,)(?=[^;]+?=)');
+
 /// Cookie manager for HTTP requests based on [CookieJar].
 class CookieManager extends Interceptor {
   const CookieManager(
@@ -70,9 +81,12 @@ class CookieManager extends Interceptor {
   }
 
   Future<void> _saveCookies(Response response) async {
-    final cookies = response.headers[HttpHeaders.setCookieHeader];
+    final setCookies = response.headers[HttpHeaders.setCookieHeader];
 
-    if (cookies != null) {
+    if (setCookies != null) {
+      final cookies = setCookies
+          .map((str) => str.split(_setCookieReg))
+          .expand((element) => element);
       await cookieJar.saveFromResponse(
         response.requestOptions.uri,
         cookies.map((str) => Cookie.fromSetCookieValue(str)).toList(),

plugins/cookie_manager/test/cookies_test.dart

@@ -49,6 +49,33 @@ void main() {
       HttpHeaders.cookieHeader: mockSecondRequestCookies,
     });
 
+    cookieManager.onRequest(options, mockRequestInterceptorHandler);
+  });
+  test('testing set-cookies parsing', () async {
+    const List<String> mockResponseCookies = [
+      'key=value; expires=Sun, 19 Feb 3000 00:42:14 GMT; path=/; HttpOnly; secure; SameSite=Lax',
+      'key1=value1; expires=Sun, 19 Feb 3000 01:43:15 GMT; path=/; HttpOnly; secure; SameSite=Lax, '
+          'key2=value2; expires=Sat, 20 May 3000 00:43:15 GMT; path=/; HttpOnly; secure; SameSite=Lax',
+    ];
+    const exampleUrl = 'https://example.com';
+
+    final expectResult = 'key=value; key1=value1; key2=value2';
+
+    final cookieJar = CookieJar();
+    final cookieManager = CookieManager(cookieJar);
+    final mockRequestInterceptorHandler =
+        MockRequestInterceptorHandler(expectResult);
+    final mockResponseInterceptorHandler = MockResponseInterceptorHandler();
+    final requestOptions = RequestOptions(baseUrl: exampleUrl);
+
+    final mockResponse = Response(
+        requestOptions: requestOptions,
+        headers: Headers.fromMap(
+          {HttpHeaders.setCookieHeader: mockResponseCookies},
+        ));
+    cookieManager.onResponse(mockResponse, mockResponseInterceptorHandler);
+    final options = RequestOptions(baseUrl: exampleUrl);
+
     cookieManager.onRequest(options, mockRequestInterceptorHandler);
   });
 }