[go_router_builder] Fixes trailing ? by comparing iterables (#8521)

Fixes flutter/flutter#127373

Author: ValentinVignal

packages/go_router_builder/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 2.7.5
+
+- Fixes trailing `?` in the location when a go route has an empty default value.
+
 ## 2.7.4
 
 - Fixes an issue by removing unnecessary `const` in StatefulShellRouteData generation.

packages/go_router_builder/example/lib/all_types.g.dart

@@ -0,0 +1,49 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter_test/flutter_test.dart';
+import 'package:go_router_builder_example/all_types.dart';
+
+void main() {
+  test('IterableRouteWithDefaultValues', () {
+    expect(
+      const IterableRouteWithDefaultValues().location,
+      '/iterable-route-with-default-values',
+    );
+
+    // Needs to not be a const to test
+    // https://github.com/flutter/flutter/issues/127825.
+    final Set<double> doubleSetField = <double>{};
+    expect(
+      IterableRouteWithDefaultValues(
+        doubleSetField: doubleSetField,
+      ).location,
+      '/iterable-route-with-default-values',
+    );
+
+    expect(
+      IterableRouteWithDefaultValues(
+        doubleSetField: <double>{0.0, 1.0},
+      ).location,
+      '/iterable-route-with-default-values?double-set-field=0.0&double-set-field=1.0',
+    );
+
+    // Needs to not be a const to test
+    // https://github.com/flutter/flutter/issues/127825.
+    final Set<int> intSetField = <int>{0, 1};
+    expect(
+      IterableRouteWithDefaultValues(
+        intSetField: intSetField,
+      ).location,
+      '/iterable-route-with-default-values',
+    );
+
+    expect(
+      const IterableRouteWithDefaultValues(
+        intSetField: <int>{0, 1, 2},
+      ).location,
+      '/iterable-route-with-default-values?int-set-field=0&int-set-field=1&int-set-field=2',
+    );
+  });
+}

packages/go_router_builder/example/test/location_test.dart

@@ -313,7 +313,9 @@ class GoRouteConfig extends RouteBaseConfig {
         if (param.type.isNullableType) {
           throw NullableDefaultValueError(param);
         }
-        conditions.add('$parameterName != ${param.defaultValueCode!}');
+        conditions.add(
+          compareField(param, parameterName, param.defaultValueCode!),
+        );
       } else if (param.type.isNullableType) {
         conditions.add('$parameterName != null');
       }
@@ -734,6 +736,7 @@ const Map<String, String> helperNames = <String, String>{
   convertMapValueHelperName: _convertMapValueHelper,
   boolConverterHelperName: _boolConverterHelper,
   enumExtensionHelperName: _enumConverterHelper,
+  iterablesEqualHelperName: _iterableEqualsHelper,
 };
 
 const String _convertMapValueHelper = '''
@@ -765,3 +768,18 @@ extension<T extends Enum> on Map<T, String> {
   T $enumExtensionHelperName(String value) =>
       entries.singleWhere((element) => element.value == value).key;
 }''';
+
+const String _iterableEqualsHelper = '''
+bool $iterablesEqualHelperName<T>(Iterable<T>? iterable1, Iterable<T>? iterable2) {
+  if (identical(iterable1, iterable2)) return true;
+  if (iterable1 == null || iterable2 == null) return false;
+  final iterator1 = iterable1.iterator;
+  final iterator2 = iterable2.iterator;
+  while (true) {
+    final hasNext1 = iterator1.moveNext();
+    final hasNext2 = iterator2.moveNext();
+    if (hasNext1 != hasNext2) return false;
+    if (!hasNext1) return true;
+    if (iterator1.current != iterator2.current) return false;
+  }
+}''';

packages/go_router_builder/lib/src/route_config.dart

@@ -28,6 +28,9 @@ const String extraFieldName = r'$extra';
 /// Shared start of error message related to a likely code issue.
 const String likelyIssueMessage = 'Should never get here! File an issue!';
 
+/// The name of the generated, private helper for comparing iterables.
+const String iterablesEqualHelperName = r'_$iterablesEqual';
+
 const List<_TypeHelper> _helpers = <_TypeHelper>[
   _TypeHelperBigInt(),
   _TypeHelperBool(),
@@ -86,6 +89,22 @@ String encodeField(PropertyAccessorElement element) {
   );
 }
 
+/// Returns the comparison of a parameter with its default value.
+///
+/// Otherwise, throws an [InvalidGenerationSourceError].
+String compareField(ParameterElement param, String value1, String value2) {
+  for (final _TypeHelper helper in _helpers) {
+    if (helper._matchesType(param.type)) {
+      return helper._compare(param.name, param.defaultValueCode!);
+    }
+  }
+
+  throw InvalidGenerationSourceError(
+    'The type `${param.type}` is not supported.',
+    element: param,
+  );
+}
+
 /// Gets the name of the `const` map generated to help encode [Enum] types.
 String enumMapName(InterfaceType type) => '_\$${type.element.name}EnumMap';
 
@@ -119,6 +138,8 @@ abstract class _TypeHelper {
   String _encode(String fieldName, DartType type);
 
   bool _matchesType(DartType type);
+
+  String _compare(String value1, String value2) => '$value1 != $value2';
 }
 
 class _TypeHelperBigInt extends _TypeHelperWithHelper {
@@ -252,9 +273,12 @@ class _TypeHelperUri extends _TypeHelperWithHelper {
       const TypeChecker.fromRuntime(Uri).isAssignableFromType(type);
 }
 
-class _TypeHelperIterable extends _TypeHelper {
+class _TypeHelperIterable extends _TypeHelperWithHelper {
   const _TypeHelperIterable();
 
+  @override
+  String helperName(DartType paramType) => iterablesEqualHelperName;
+
   @override
   String _decode(
       ParameterElement parameterElement, Set<String> pathParameters) {
@@ -324,6 +348,10 @@ $fieldName$nullAwareAccess.map((e) => e.toString()).toList()''';
   @override
   bool _matchesType(DartType type) =>
       const TypeChecker.fromRuntime(Iterable).isAssignableFromType(type);
+
+  @override
+  String _compare(String value1, String value2) =>
+      '!$iterablesEqualHelperName($value1, $value2)';
 }
 
 abstract class _TypeHelperWithHelper extends _TypeHelper {

packages/go_router_builder/lib/src/type_helpers.dart

@@ -2,7 +2,7 @@ name: go_router_builder
 description: >-
   A builder that supports generated strongly-typed route helpers for
   package:go_router
-version: 2.7.4
+version: 2.7.5
 repository: https://github.com/flutter/packages/tree/main/packages/go_router_builder
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+go_router_builder%22
 

packages/go_router_builder/pubspec.yaml

@@ -13,7 +13,7 @@ extension $IterableDefaultValueRouteExtension on IterableDefaultValueRoute {
   String get location => GoRouteData.$location(
         '/iterable-default-value-route',
         queryParams: {
-          if (param != const <int>[0])
+          if (!_$iterablesEqual(param, const <int>[0]))
             'param': param.map((e) => e.toString()).toList(),
         },
       );
@@ -27,3 +27,17 @@ extension $IterableDefaultValueRouteExtension on IterableDefaultValueRoute {
 
   void replace(BuildContext context) => context.replace(location);
 }
+
+bool _$iterablesEqual<T>(Iterable<T>? iterable1, Iterable<T>? iterable2) {
+  if (identical(iterable1, iterable2)) return true;
+  if (iterable1 == null || iterable2 == null) return false;
+  final iterator1 = iterable1.iterator;
+  final iterator2 = iterable2.iterator;
+  while (true) {
+    final hasNext1 = iterator1.moveNext();
+    final hasNext2 = iterator2.moveNext();
+    if (hasNext1 != hasNext2) return false;
+    if (!hasNext1) return true;
+    if (iterator1.current != iterator2.current) return false;
+  }
+}

packages/go_router_builder/test_inputs/iterable_with_default_value.dart.expect

@@ -23,7 +23,7 @@ extension $ListRouteExtension on ListRoute {
           'ids': ids.map((e) => e.toString()).toList(),
           if (nullableIds != null)
             'nullable-ids': nullableIds?.map((e) => e.toString()).toList(),
-          if (idsWithDefaultValue != const <int>[0])
+          if (!_$iterablesEqual(idsWithDefaultValue, const <int>[0]))
             'ids-with-default-value':
                 idsWithDefaultValue.map((e) => e.toString()).toList(),
         },
@@ -38,3 +38,17 @@ extension $ListRouteExtension on ListRoute {
 
   void replace(BuildContext context) => context.replace(location);
 }
+
+bool _$iterablesEqual<T>(Iterable<T>? iterable1, Iterable<T>? iterable2) {
+  if (identical(iterable1, iterable2)) return true;
+  if (iterable1 == null || iterable2 == null) return false;
+  final iterator1 = iterable1.iterator;
+  final iterator2 = iterable2.iterator;
+  while (true) {
+    final hasNext1 = iterator1.moveNext();
+    final hasNext2 = iterator2.moveNext();
+    if (hasNext1 != hasNext2) return false;
+    if (!hasNext1) return true;
+    if (iterator1.current != iterator2.current) return false;
+  }
+}

packages/go_router_builder/test_inputs/list.dart.expect

@@ -23,7 +23,7 @@ extension $SetRouteExtension on SetRoute {
           'ids': ids.map((e) => e.toString()).toList(),
           if (nullableIds != null)
             'nullable-ids': nullableIds?.map((e) => e.toString()).toList(),
-          if (idsWithDefaultValue != const <int>{0})
+          if (!_$iterablesEqual(idsWithDefaultValue, const <int>{0}))
             'ids-with-default-value':
                 idsWithDefaultValue.map((e) => e.toString()).toList(),
         },
@@ -38,3 +38,17 @@ extension $SetRouteExtension on SetRoute {
 
   void replace(BuildContext context) => context.replace(location);
 }
+
+bool _$iterablesEqual<T>(Iterable<T>? iterable1, Iterable<T>? iterable2) {
+  if (identical(iterable1, iterable2)) return true;
+  if (iterable1 == null || iterable2 == null) return false;
+  final iterator1 = iterable1.iterator;
+  final iterator2 = iterable2.iterator;
+  while (true) {
+    final hasNext1 = iterator1.moveNext();
+    final hasNext2 = iterator2.moveNext();
+    if (hasNext1 != hasNext2) return false;
+    if (!hasNext1) return true;
+    if (iterator1.current != iterator2.current) return false;
+  }
+}