[go_router_builder] Add support for relative routes

packages/go_router/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 14.2.1
+- Allows going to a path relatively by prefixing `./`
+- Adds `TypedRelativeGoRoute`
+
 ## 14.2.0
 
 - Added proper `redirect` handling for `ShellRoute.$route` and `StatefulShellRoute.$route` for proper redirection handling in case of code generation.

packages/go_router/example/lib/go_relative.dart

@@ -0,0 +1,120 @@
+// 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/material.dart';
+import 'package:go_router/go_router.dart';
+
+/// This sample app demonstrates how to use go relatively with GoRouter.go('./$path').
+void main() => runApp(const MyApp());
+
+/// The route configuration.
+final GoRouter _router = GoRouter(
+  routes: <RouteBase>[
+    GoRoute(
+      path: '/',
+      builder: (BuildContext context, GoRouterState state) {
+        return const HomeScreen();
+      },
+      routes: <RouteBase>[
+        GoRoute(
+          path: 'details',
+          builder: (BuildContext context, GoRouterState state) {
+            return const DetailsScreen();
+          },
+          routes: <RouteBase>[
+            GoRoute(
+              path: 'settings',
+              builder: (BuildContext context, GoRouterState state) {
+                return const SettingsScreen();
+              },
+            ),
+          ],
+        ),
+      ],
+    ),
+  ],
+);
+
+/// The main app.
+class MyApp extends StatelessWidget {
+  /// Constructs a [MyApp]
+  const MyApp({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp.router(
+      routerConfig: _router,
+    );
+  }
+}
+
+/// The home screen
+class HomeScreen extends StatelessWidget {
+  /// Constructs a [HomeScreen]
+  const HomeScreen({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(title: const Text('Home Screen')),
+      body: Center(
+        child: Column(
+          mainAxisAlignment: MainAxisAlignment.center,
+          children: <Widget>[
+            ElevatedButton(
+              onPressed: () => context.go('./details'),
+              child: const Text('Go to the Details screen'),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+/// The details screen
+class DetailsScreen extends StatelessWidget {
+  /// Constructs a [DetailsScreen]
+  const DetailsScreen({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(title: const Text('Details Screen')),
+      body: Center(
+          child: Column(
+        children: <Widget>[
+          TextButton(
+            onPressed: () {
+              context.pop();
+            },
+            child: const Text('go back'),
+          ),
+          TextButton(
+            onPressed: () {
+              context.go('./settings');
+            },
+            child: const Text('Go to the Settings screen'),
+          ),
+        ],
+      )),
+    );
+  }
+}
+
+/// The settings screen
+class SettingsScreen extends StatelessWidget {
+  /// Constructs a [SettingsScreen]
+  const SettingsScreen({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(title: const Text('Settings Screen')),
+      body: const Center(
+        child: Text('Settings'),
+      ),
+    );
+  }
+}

packages/go_router/example/test/go_relative_test.dart

@@ -0,0 +1,21 @@
+// 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_examples/go_relative.dart' as example;
+
+void main() {
+  testWidgets('example works', (WidgetTester tester) async {
+    await tester.pumpWidget(const example.MyApp());
+    expect(find.byType(example.HomeScreen), findsOneWidget);
+
+    await tester.tap(find.text('Go to the Details screen'));
+    await tester.pumpAndSettle();
+    expect(find.byType(example.DetailsScreen), findsOneWidget);
+
+    await tester.tap(find.text('Go to the Settings screen'));
+    await tester.pumpAndSettle();
+    expect(find.byType(example.SettingsScreen), findsOneWidget);
+  });
+}

packages/go_router/lib/src/information_provider.dart

@@ -10,6 +10,7 @@ import 'package:flutter/services.dart';
 import 'package:flutter/widgets.dart';
 
 import 'match.dart';
+import 'path_utils.dart';
 
 /// The type of the navigation.
 ///
@@ -135,11 +136,16 @@ class GoRouteInformationProvider extends RouteInformationProvider
   }
 
   void _setValue(String location, Object state) {
-    final Uri uri = Uri.parse(location);
+    Uri uri = Uri.parse(location);
+
+    // Check for relative location
+    if (location.startsWith('./')) {
+      uri = concatenateUris(_value.uri, uri);
+    }
 
     final bool shouldNotify =
         _valueHasChanged(newLocationUri: uri, newState: state);
-    _value = RouteInformation(uri: Uri.parse(location), state: state);
+    _value = RouteInformation(uri: uri, state: state);
     if (shouldNotify) {
       notifyListeners();
     }

packages/go_router/lib/src/path_utils.dart

@@ -119,6 +119,20 @@ String concatenatePaths(String parentPath, String childPath) {
   return '${parentPath == '/' ? '' : parentPath}/$childPath';
 }
 
+/// Concatenates two Uri. It will [concatenatePaths] the parent's and the child's paths, and take only the child's parameters.
+///
+/// e.g: pathA = /a?fid=f1, pathB = c/d?pid=p2,  concatenatePaths(pathA, pathB) = /a/c/d?pid=2.
+Uri concatenateUris(Uri parentUri, Uri childUri) {
+  Uri newUri = parentUri.replace(
+    path: concatenatePaths(parentUri.path, childUri.path),
+    queryParameters: childUri.queryParameters,
+  );
+
+  // Parse the new normalized uri to remove unnecessary parts, like the trailing '?'.
+  newUri = Uri.parse(canonicalUri(newUri.toString()));
+  return newUri;
+}
+
 /// Normalizes the location string.
 String canonicalUri(String loc) {
   if (loc.isEmpty) {

packages/go_router/lib/src/route_data.dart

@@ -390,6 +390,28 @@ class TypedGoRoute<T extends GoRouteData> extends TypedRoute<T> {
   final List<TypedRoute<RouteData>> routes;
 }
 
+/// A superclass for each typed go route descendant
+@Target(<TargetKind>{TargetKind.library, TargetKind.classType})
+class TypedRelativeGoRoute<T extends GoRouteData> extends TypedRoute<T> {
+  /// Default const constructor
+  const TypedRelativeGoRoute({
+    required this.path,
+    this.routes = const <TypedRoute<RouteData>>[],
+  });
+
+  /// The relative path that corresponds to this route.
+  ///
+  /// See [GoRoute.path].
+  ///
+  ///
+  final String path;
+
+  /// Child route definitions.
+  ///
+  /// See [RouteBase.routes].
+  final List<TypedRoute<RouteData>> routes;
+}
+
 /// A superclass for each typed shell route descendant
 @Target(<TargetKind>{TargetKind.library, TargetKind.classType})
 class TypedShellRoute<T extends ShellRouteData> extends TypedRoute<T> {

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: 14.2.0
+version: 14.2.1
 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