content [nfc]: Follow browser preference setting when opening links

This preserves the previous behavior (external application on iOS,
and in-app browser on Android) when browserPreference is `null`.

There is no way for the client to update the setting for now, hence the
NFC.

The helper could have been a static method instead of an extension,
similar to ThemeSetting.displayName, but that will be a lot more verbose
for the caller.

Signed-off-by: Zixuan James Li <zixuan@zulip.com>

Author: PIG208

lib/model/settings.dart

@@ -48,7 +48,8 @@ enum BrowserPreference {
 }
 
 extension GlobalSettingsHelpers on GlobalSettingsData {
-  BrowserPreference get defaultBrowserPreference {
+  BrowserPreference get effectiveBrowserPreference {
+    if (browserPreference != null) return browserPreference!;
     return switch (defaultTargetPlatform) {
       // On iOS we prefer UrlLaunchMode.externalApplication because (for
       // HTTP URLs) UrlLaunchMode.platformDefault uses SFSafariViewController,
@@ -64,7 +65,7 @@ extension GlobalSettingsHelpers on GlobalSettingsData {
   }
 
   UrlLaunchMode getUrlLaunchMode(Uri url) {
-    switch (defaultBrowserPreference) {
+    switch (effectiveBrowserPreference) {
       case BrowserPreference.inApp:
         if (!(url.scheme == 'https' || url.scheme == 'http')) {
           // For URLs on non-HTTP schemes such as `mailto`,

test/model/settings_test.dart

@@ -2,6 +2,7 @@ import 'package:checks/checks.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:zulip/model/binding.dart';
+import 'package:zulip/model/settings.dart';
 
 import '../example_data.dart' as eg;
 import 'store_checks.dart';
@@ -12,20 +13,41 @@ void main() {
   final nonHttpLink = Uri.parse('mailto:chat@zulip.org');
 
   group('getUrlLaunchMode', () {
-    testAndroidIos('use our per-platform defaults for HTTP links', () {
+    testAndroidIos('globalSettings.browserPreference is null; use our per-platform defaults for HTTP links', () {
       final globalStore = eg.globalStore(globalSettings: eg.globalSettings(
         browserPreference: null));
       check(globalStore).globalSettings.getUrlLaunchMode(httpLink).equals(
         defaultTargetPlatform == TargetPlatform.iOS
           ? UrlLaunchMode.externalApplication : UrlLaunchMode.inAppBrowserView);
     });
 
-    testAndroidIos('use our per-platform defaults for non-HTTP links', () {
+    testAndroidIos('globalSettings.browserPreference is null; use our per-platform defaults for non-HTTP links', () {
       final globalStore = eg.globalStore(globalSettings: eg.globalSettings(
         browserPreference: null));
       check(globalStore).globalSettings.getUrlLaunchMode(nonHttpLink).equals(
         defaultTargetPlatform == TargetPlatform.android
           ? UrlLaunchMode.platformDefault : UrlLaunchMode.externalApplication);
     });
+
+    testAndroidIos('globalSettings.browserPreference is inApp; follow the user preference for http links', () {
+      final globalStore = eg.globalStore(globalSettings: eg.globalSettings(
+        browserPreference: BrowserPreference.inApp));
+      check(globalStore).globalSettings.getUrlLaunchMode(httpLink).equals(
+        UrlLaunchMode.inAppBrowserView);
+    });
+
+    testAndroidIos('globalSettings.browserPreference is inApp; use platform default for non-http links', () {
+      final globalStore = eg.globalStore(globalSettings: eg.globalSettings(
+        browserPreference: BrowserPreference.inApp));
+      check(globalStore).globalSettings.getUrlLaunchMode(nonHttpLink).equals(
+        UrlLaunchMode.platformDefault);
+    });
+
+    testAndroidIos('globalSettings.browserPreference is external; follow the user preference', () {
+      final globalStore = eg.globalStore(globalSettings: eg.globalSettings(
+        browserPreference: BrowserPreference.external));
+      check(globalStore).globalSettings.getUrlLaunchMode(httpLink).equals(
+        UrlLaunchMode.externalApplication);
+    });
   });
 }

test/model/store_checks.dart

@@ -33,7 +33,7 @@ extension GlobalStoreChecks on Subject<GlobalStore> {
 extension GlobalSettingsDataChecks on Subject<GlobalSettingsData> {
   Subject<ThemeSetting?> get themeSetting => has((x) => x.themeSetting, 'themeSetting');
   Subject<BrowserPreference?> get browserPreference => has((x) => x.browserPreference, 'browserPreference');
-  Subject<BrowserPreference> get defaultBrowserPreference => has((x) => x.defaultBrowserPreference, 'defaultBrowserPreference');
+  Subject<BrowserPreference> get effectiveBrowserPreference => has((x) => x.effectiveBrowserPreference, 'effectiveBrowserPreference');
   Subject<UrlLaunchMode> getUrlLaunchMode(Uri url) => has((x) => x.getUrlLaunchMode(url), 'getUrlLaunchMode');
 }
 

test/widgets/content_test.dart

@@ -9,6 +9,7 @@ import 'package:url_launcher/url_launcher.dart';
 import 'package:zulip/api/core.dart';
 import 'package:zulip/model/content.dart';
 import 'package:zulip/model/narrow.dart';
+import 'package:zulip/model/settings.dart';
 import 'package:zulip/model/store.dart';
 import 'package:zulip/widgets/content.dart';
 import 'package:zulip/widgets/icons.dart';
@@ -798,6 +799,18 @@ void main() {
         .single.equals((url: Uri.parse('https://example/'), mode: expectedLaunchMode));
     }, variant: const TargetPlatformVariant({TargetPlatform.android, TargetPlatform.iOS}));
 
+    testWidgets('follow browser preference setting to open URL', (tester) async {
+      await testBinding.globalStore.updateGlobalSettings(
+        eg.globalSettings(
+          browserPreference: BrowserPreference.inApp).toCompanion(false));
+      await prepare(tester,
+        '<p><a href="https://example/">hello</a></p>');
+
+      await tapText(tester, find.text('hello'));
+      check(testBinding.takeLaunchUrlCalls()).single.equals((
+        url: Uri.parse('https://example/'), mode: LaunchMode.inAppBrowserView));
+    }, variant: const TargetPlatformVariant({TargetPlatform.android, TargetPlatform.iOS}));
+
     testWidgets('multiple links in paragraph', (tester) async {
       const fontSize = kBaseFontSize;