[go_router_builder] Support custom types (#11068)

Closes flutter/flutter#112152
Closes flutter/flutter#110781

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Author: ValentinVignal

packages/go_router_builder/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 4.3.0
+
+- Adds support for custom types through `TypedQueryParameter` annotation. The `encoder`, `decoder` and `compare` parameters allow specifying custom functions for encoding, decoding and comparing query parameters in `TypedGoRoute` constructors. For example, you can use a `DateTime` parameter with a custom encoder and decoder to convert it to and from a string representation in the URL.
+
 ## 4.2.1
 
 * Adds support for analyzer 11 and 12.

packages/go_router_builder/example/lib/typed_query_parameter_example.dart

@@ -11,6 +11,29 @@ part 'typed_query_parameter_example.g.dart';
 
 void main() => runApp(App());
 
+class CustomParameter {
+  const CustomParameter({required this.valueString, required this.valueInt});
+
+  final String valueString;
+  final int valueInt;
+
+  static String encode(CustomParameter parameter) {
+    return '${parameter.valueString},${parameter.valueInt}';
+  }
+
+  static CustomParameter decode(String value) {
+    final List<String> parts = value.split(',');
+    return CustomParameter(
+      valueString: parts[0],
+      valueInt: int.parse(parts[1]),
+    );
+  }
+
+  static bool compare(CustomParameter a, CustomParameter b) {
+    return a.valueString != b.valueString || a.valueInt != b.valueInt;
+  }
+}
+
 class App extends StatelessWidget {
   App({super.key});
 
@@ -31,30 +54,52 @@ class IntRoute extends GoRouteData with $IntRoute {
     @TypedQueryParameter(name: 'int_field_with_default_value')
     this.intFieldWithDefaultValue = 1,
     @TypedQueryParameter(name: 'int field') this.intFieldWithSpace,
+    @TypedQueryParameter<CustomParameter>(
+      encoder: CustomParameter.encode,
+      decoder: CustomParameter.decode,
+    )
+    this.customField,
+    @TypedQueryParameter<CustomParameter>(
+      encoder: CustomParameter.encode,
+      decoder: CustomParameter.decode,
+      compare: CustomParameter.compare,
+    )
+    this.customFieldWithDefaultValue = const CustomParameter(
+      valueString: 'default',
+      valueInt: 0,
+    ),
   });
 
   final int? intField;
   final int intFieldWithDefaultValue;
   final int? intFieldWithSpace;
+  final CustomParameter? customField;
+  final CustomParameter customFieldWithDefaultValue;
   @override
   Widget build(BuildContext context, GoRouterState state) => Screen(
     intField: intField,
     intFieldWithDefaultValue: intFieldWithDefaultValue,
     intFieldWithSpace: intFieldWithSpace,
+    customField: customField,
+    customFieldWithDefaultValue: customFieldWithDefaultValue,
   );
 }
 
 class Screen extends StatelessWidget {
   const Screen({
+    super.key,
     required this.intField,
     required this.intFieldWithDefaultValue,
     this.intFieldWithSpace,
-    super.key,
+    this.customField,
+    required this.customFieldWithDefaultValue,
   });
 
   final int? intField;
   final int intFieldWithDefaultValue;
   final int? intFieldWithSpace;
+  final CustomParameter? customField;
+  final CustomParameter customFieldWithDefaultValue;
 
   @override
   Widget build(BuildContext context) => Scaffold(
@@ -75,6 +120,8 @@ class Screen extends StatelessWidget {
                 intField: newValue,
                 intFieldWithDefaultValue: intFieldWithDefaultValue,
                 intFieldWithSpace: intFieldWithSpace,
+                customField: customField,
+                customFieldWithDefaultValue: customFieldWithDefaultValue,
               ).go(context);
             },
           ),
@@ -88,6 +135,8 @@ class Screen extends StatelessWidget {
                 intField: intField,
                 intFieldWithDefaultValue: newValue,
                 intFieldWithSpace: intFieldWithSpace,
+                customField: customField,
+                customFieldWithDefaultValue: customFieldWithDefaultValue,
               ).go(context);
             },
           ),
@@ -101,6 +150,46 @@ class Screen extends StatelessWidget {
                 intField: intField,
                 intFieldWithDefaultValue: intFieldWithDefaultValue,
                 intFieldWithSpace: newValue,
+                customField: customField,
+                customFieldWithDefaultValue: customFieldWithDefaultValue,
+              ).go(context);
+            },
+          ),
+          ListTile(
+            title: const Text('customField:'),
+            subtitle: Text(
+              customField == null ? '' : CustomParameter.encode(customField!),
+            ),
+            trailing: const Icon(Icons.add),
+            onTap: () {
+              final newValue = CustomParameter(
+                valueString: '${customField?.valueString ?? ''}-',
+                valueInt: (customField?.valueInt ?? 0) + 1,
+              );
+              IntRoute(
+                intField: intField,
+                intFieldWithDefaultValue: intFieldWithDefaultValue,
+                intFieldWithSpace: intFieldWithSpace,
+                customField: newValue,
+                customFieldWithDefaultValue: customFieldWithDefaultValue,
+              ).go(context);
+            },
+          ),
+          ListTile(
+            title: const Text('customFieldWithDefaultValue:'),
+            subtitle: Text(CustomParameter.encode(customFieldWithDefaultValue)),
+            trailing: const Icon(Icons.add),
+            onTap: () {
+              final newValue = CustomParameter(
+                valueString: '${customFieldWithDefaultValue.valueString}-',
+                valueInt: customFieldWithDefaultValue.valueInt + 1,
+              );
+              IntRoute(
+                intField: intField,
+                intFieldWithDefaultValue: intFieldWithDefaultValue,
+                intFieldWithSpace: intFieldWithSpace,
+                customField: customField,
+                customFieldWithDefaultValue: newValue,
               ).go(context);
             },
           ),

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

@@ -9,7 +9,7 @@ dependencies:
   collection: ^1.15.0
   flutter:
     sdk: flutter
-  go_router: ^17.1.0
+  go_router: ^17.2.0
   provider: 6.0.5
 
 dev_dependencies:

packages/go_router_builder/example/pubspec.yaml

@@ -40,4 +40,23 @@ void main() {
     );
     expect(find.text('2'), findsOne);
   });
+
+  testWidgets('It should modify the custom fields when tapped', (tester) async {
+    await tester.pumpWidget(App());
+
+    expect(find.text('customField:'), findsOne);
+    expect(find.text('customFieldWithDefaultValue:'), findsOne);
+
+    expect(find.text('default,0'), findsOne);
+
+    await tester.tap(find.text('customField:'));
+    await tester.pumpAndSettle();
+    expect(find.text('-,1'), findsOne);
+    expect(find.text('default,0'), findsOne);
+
+    await tester.tap(find.text('customFieldWithDefaultValue:'));
+    await tester.pumpAndSettle();
+    expect(find.text('-,1'), findsOne);
+    expect(find.text('default-,1'), findsOne);
+  });
 }

packages/go_router_builder/example/test/typed_query_parameter_test.dart

@@ -323,9 +323,7 @@ mixin _GoRouteMixin on RouteBaseConfig {
         if (param.type.isNullableType) {
           throw NullableDefaultValueError(param);
         }
-        conditions.add(
-          compareField(param, parameterName, param.defaultValueCode!),
-        );
+        conditions.add(compareField(param));
       } else if (param.type.isNullableType) {
         conditions.add('$selfFieldName.$parameterName != null');
       }