feat: add prev and next buttons to the address bar on pointer platforms

app/lib/presentation/reader/address_bar.dart

@@ -1,12 +1,14 @@
+import 'package:flutter/foundation.dart' show defaultTargetPlatform, TargetPlatform;
 import 'package:flutter/material.dart';
 import 'package:signals/signals_flutter.dart' show SignalBuilder;
 
 import '../../application/internal_pages.dart';
 import '../app.dart';
 
-/// The single-field address bar. The left icon opens the settings page; the
+/// The single-field address bar. The left icon opens the settings page and,
-/// right icons reload, subscribe (only when the page offers something to
+/// on pointer platforms, carries the back and forward buttons; the right
-/// subscribe to) and bookmark the current page.
+/// icons reload, subscribe (only when the page offers something to subscribe
+/// to) and bookmark the current page.
 class AddressBar extends StatefulWidget {
   const AddressBar({super.key});
 
@@ -52,6 +54,14 @@ class _AddressBarState extends State<AddressBar> {
         _controller.text = url;
       }
 
+      // Touch devices navigate with swipes; desktops get buttons.
+      final hasButtons = switch (defaultTargetPlatform) {
+        TargetPlatform.linux ||
+        TargetPlatform.windows ||
+        TargetPlatform.macOS => true,
+        _ => false,
+      };
+
       // Only pages with dated entry links or an Atom feed can be subscribed
       // to (mews spec, section 6).
       final canSubscribe = page != null &&
@@ -79,12 +89,41 @@ class _AddressBarState extends State<AddressBar> {
             labelText: strings.t('reader-address-label'),
             isDense: true,
             border: const OutlineInputBorder(),
-            prefixIcon: IconButton(
+            prefixIcon: hasButtons
+                ? Row(
+                    mainAxisSize: MainAxisSize.min,
+                    children: [
+                      IconButton(
                         icon: const Icon(Icons.tune),
                         tooltip: strings.t('reader-open-settings'),
                         onPressed: () =>
                             deps.browser.open(InternalPages.settingsUrl),
                       ),
+                      IconButton(
+                        icon: const Icon(Icons.arrow_back),
+                        tooltip: strings.t('reader-back'),
+                        onPressed: deps.browser.canGoBack
+                            ? deps.browser.back
+                            : null,
+                      ),
+                      IconButton(
+                        icon: const Icon(Icons.arrow_forward),
+                        tooltip: strings.t('reader-forward'),
+                        onPressed: deps.browser.canGoForward
+                            ? deps.browser.forward
+                            : null,
+                      ),
+                    ],
+                  )
+                : IconButton(
+                    icon: const Icon(Icons.tune),
+                    tooltip: strings.t('reader-open-settings'),
+                    onPressed: () =>
+                        deps.browser.open(InternalPages.settingsUrl),
+                  ),
+            prefixIconConstraints: hasButtons
+                ? const BoxConstraints(minWidth: 138, minHeight: 48)
+                : null,
             suffixIcon: Row(
               mainAxisSize: MainAxisSize.min,
               children: [

app/locales/en-US/main.ftl

@@ -5,6 +5,8 @@ reader-address-placeholder = Enter a web address
 reader-address-label = Web address
 reader-reload = Reload this page
 reader-open-settings = Open settings
+reader-back = Go back
+reader-forward = Go forward
 
 ## Settings page
 

app/test/app_widget_test.dart

@@ -1,6 +1,7 @@
 import 'dart:io' show File;
 
 import 'package:actors/actors.dart';
+import 'package:flutter/foundation.dart' show TargetPlatform, debugDefaultTargetPlatformOverride;
 import 'package:drift/native.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_test/flutter_test.dart';
@@ -383,6 +384,45 @@ void main() {
     expect(find.textContaining('Page A'), findsOneWidget);
   });
 
+  testWidgets('prev and next buttons navigate on pointer platforms',
+      (tester) async {
+    final stubDeps = AppDependencies(
+      database: MewsDatabase.test(NativeDatabase.memory()),
+      fetch: _FakeFetch({
+        'https://example.com/a.html':
+            _page('Page A', '<h1>Page A</h1><p>The first pages content.</p>'),
+        'https://example.com/b.html':
+            _page('Page B', '<h1>Page B</h1><p>The second pages content.</p>'),
+      }),
+      strings: strings,
+    );
+    // Test bindings default to android; a Linux host shows the buttons.
+    debugDefaultTargetPlatformOverride = TargetPlatform.linux;
+
+    await tester.pumpWidget(MewsApp(deps: stubDeps, strings: strings));
+    await tester.pumpAndSettle();
+
+    final back = find.byIcon(Icons.arrow_back);
+    final forward = find.byIcon(Icons.arrow_forward);
+    expect(back, findsOneWidget);
+    expect(forward, findsOneWidget);
+
+    await stubDeps.browser.open('https://example.com/a.html');
+    await stubDeps.browser.open('https://example.com/b.html');
+    await tester.pumpAndSettle();
+
+    await tester.tap(back);
+    await tester.pumpAndSettle();
+    expect(stubDeps.browser.currentPage.value?.url, 'https://example.com/a.html');
+
+    await tester.tap(forward);
+    await tester.pumpAndSettle();
+    expect(stubDeps.browser.currentPage.value?.url, 'https://example.com/b.html');
+
+    // The invariant check runs before test tear-downs, so reset by hand.
+    debugDefaultTargetPlatformOverride = null;
+  });
+
   testWidgets('reports new posts once per page', (tester) async {
     await pumpApp(tester);