[go_router] Add routing functions to GoRouteData (#9277)

second step of fixing [#106790](flutter/flutter#106790). [First PR](#9275)

This PR adds the routing methods `.location`, `.go(context)`, `.push(context)`, `.pushReplacement(context)`, and `replace(context)` to `GoRouteData`. They will be overridden by the mixin generated by `go_router_builder`

## Pre-Review Checklist

[^1]: Regular contributors who have demonstrated familiarity with the repository guidelines only need to comment if the PR is not auto-exempted by repo tooling.

Author: StevenSorial

packages/go_router/CHANGELOG.md

@@ -1,8 +1,13 @@
+## 15.2.0
+
+- `GoRouteData` now defines `.location`, `.go(context)`, `.push(context)`, `.pushReplacement(context)`, and `replace(context)` to be used for [Type-safe routing](https://pub.dev/documentation/go_router/latest/topics/Type-safe%20routes-topic.html). **Requires go_router_builder >= 3.0.0**.
+
 ## 15.1.3
 
 * Updates minimum supported SDK version to Flutter 3.27/Dart 3.6.
 * Fixes typo in API docs.
 
+
 ## 15.1.2
 
 - Fixes focus request propagation from `GoRouter` to `Navigator` by properly handling the `requestFocus` parameter.

packages/go_router/lib/src/route_data.dart

@@ -133,6 +133,30 @@ abstract class GoRouteData extends RouteData {
   static final Expando<GoRouteData> _stateObjectExpando = Expando<GoRouteData>(
     'GoRouteState to GoRouteData expando',
   );
+
+  /// The location of this route.
+  String get location => throw _shouldBeGeneratedError;
+
+  /// Navigate to the route.
+  void go(BuildContext context) => throw _shouldBeGeneratedError;
+
+  /// Push the route onto the page stack.
+  Future<T?> push<T>(BuildContext context) => throw _shouldBeGeneratedError;
+
+  /// Replaces the top-most page of the page stack with the route.
+  void pushReplacement(BuildContext context) => throw _shouldBeGeneratedError;
+
+  /// Replaces the top-most page of the page stack with the route but treats
+  /// it as the same page.
+  ///
+  /// The page key will be reused. This will preserve the state and not run any
+  /// page animation.
+  ///
+  void replace(BuildContext context) => throw _shouldBeGeneratedError;
+
+  static UnimplementedError get _shouldBeGeneratedError => UnimplementedError(
+        'Should be generated using [Type-safe routing](https://pub.dev/documentation/go_router/latest/topics/Type-safe%20routes-topic.html).',
+      );
 }
 
 /// A class to represent a [ShellRoute] in

packages/go_router/pubspec.yaml

@@ -1,7 +1,7 @@
 name: go_router
 description: A declarative router for Flutter based on Navigation 2 supporting
   deep linking, data-driven routes and more
-version: 15.1.3
+version: 15.2.0
 repository: https://github.com/flutter/packages/tree/main/packages/go_router
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+go_router%22
 

packages/go_router/test/route_data_test.dart

@@ -280,6 +280,76 @@ void main() {
         expect(routeWithDefaultCaseSensitivity.caseSensitive, false);
       },
     );
+
+    testWidgets(
+      'It should throw beacuase there is no code generated',
+      (WidgetTester tester) async {
+        final List<FlutterErrorDetails> errors = <FlutterErrorDetails>[];
+
+        FlutterError.onError =
+            (FlutterErrorDetails details) => errors.add(details);
+
+        const String errorText = 'Should be generated';
+
+        Widget buildWidget(void Function(BuildContext) onTap) {
+          return MaterialApp(
+            home: Builder(
+              builder: (BuildContext context) => GestureDetector(
+                child: const Text('Tap'),
+                onTap: () => onTap(context),
+              ),
+            ),
+          );
+        }
+
+        final Widget pushThrower = buildWidget((BuildContext context) {
+          const _GoRouteDataBuild().push<void>(context);
+        });
+        await tester.pumpWidget(pushThrower);
+        await tester.tap(find.text('Tap'));
+
+        expect(errors.first.exception, isA<UnimplementedError>());
+        expect(errors.first.exception.toString(), contains(errorText));
+
+        errors.clear();
+
+        final Widget goThrower = buildWidget((BuildContext context) {
+          const _GoRouteDataBuild().go(context);
+        });
+        await tester.pumpWidget(goThrower);
+        await tester.tap(find.text('Tap'));
+
+        expect(errors.first.exception, isA<UnimplementedError>());
+        expect(errors.first.exception.toString(), contains(errorText));
+
+        errors.clear();
+
+        final Widget pushReplacementThrower =
+            buildWidget((BuildContext context) {
+          const _GoRouteDataBuild().pushReplacement(context);
+        });
+        await tester.pumpWidget(pushReplacementThrower);
+        await tester.tap(find.text('Tap'));
+
+        expect(errors.first.exception, isA<UnimplementedError>());
+        expect(errors.first.exception.toString(), contains(errorText));
+
+        errors.clear();
+
+        final Widget replaceThrower = buildWidget((BuildContext context) {
+          const _GoRouteDataBuild().pushReplacement(context);
+        });
+        await tester.pumpWidget(replaceThrower);
+        await tester.tap(find.text('Tap'));
+
+        expect(errors.first.exception, isA<UnimplementedError>());
+        expect(errors.first.exception.toString(), contains(errorText));
+
+        errors.clear();
+
+        FlutterError.onError = FlutterError.dumpErrorToConsole;
+      },
+    );
   });
 
   group('ShellRouteData', () {