Add feature flags to advanced preferences

Packages/TuskerPreferences/Sources/TuskerPreferences/Preferences.swift

@@ -97,6 +97,9 @@ public class Preferences: Codable, ObservableObject {
         self.hideTrends = try container.decodeIfPresent(Bool.self, forKey: .hideTrends) ?? false
         
         self.statusContentType = try container.decode(StatusContentType.self, forKey: .statusContentType)
+        self.reportErrorsAutomatically = try container.decodeIfPresent(Bool.self, forKey: .reportErrorsAutomatically) ?? true
+        let featureFlagNames = (try? container.decodeIfPresent([String].self, forKey: .enabledFeatureFlags)) ?? []
+        self.enabledFeatureFlags = Set(featureFlagNames.compactMap(FeatureFlag.init))
         
         self.hasShownLocalTimelineDescription = try container.decodeIfPresent(Bool.self, forKey: .hasShownLocalTimelineDescription) ?? false
         self.hasShownFederatedTimelineDescription = try container.decodeIfPresent(Bool.self, forKey: .hasShownFederatedTimelineDescription) ?? false
@@ -149,6 +152,8 @@ public class Preferences: Codable, ObservableObject {
         try container.encode(hideTrends, forKey: .hideTrends)
         
         try container.encode(statusContentType, forKey: .statusContentType)
+        try container.encode(reportErrorsAutomatically, forKey: .reportErrorsAutomatically)
+        try container.encode(enabledFeatureFlags, forKey: .enabledFeatureFlags)
         
         try container.encode(hasShownLocalTimelineDescription, forKey: .hasShownLocalTimelineDescription)
         try container.encode(hasShownFederatedTimelineDescription, forKey: .hasShownFederatedTimelineDescription)
@@ -213,6 +218,7 @@ public class Preferences: Codable, ObservableObject {
     // MARK: Advanced
     @Published public var statusContentType: StatusContentType = .plain
     @Published public var reportErrorsAutomatically = true
+    @Published public var enabledFeatureFlags: Set<FeatureFlag> = []
     
     // MARK:
     @Published public var hasShownLocalTimelineDescription = false
@@ -264,6 +270,8 @@ public class Preferences: Codable, ObservableObject {
         case hideTrends = "hideDiscover"
         
         case statusContentType
+        case reportErrorsAutomatically
+        case enabledFeatureFlags
         
         case hasShownLocalTimelineDescription
         case hasShownFederatedTimelineDescription
@@ -414,3 +422,9 @@ extension Preferences {
         case icloud
     }
 }
+
+extension Preferences {
+    public enum FeatureFlag: String, Codable {
+        case test
+    }
+}

Tusker/Screens/Preferences/AdvancedPrefsView.swift

@@ -16,6 +16,8 @@ struct AdvancedPrefsView : View {
     @State private var imageCacheSize: Int64 = 0
     @State private var mastodonCacheSize: Int64 = 0
     @State private var cloudKitStatus: CKAccountStatus?
+    @State private var isShowingFeatureFlagAlert = false
+    @State private var featureFlagName = ""
     
     var body: some View {
         List {
@@ -23,9 +25,27 @@ struct AdvancedPrefsView : View {
             cloudKitSection
             errorReportingSection
             cachingSection
+            featureFlagSection
+            
         }
         .listStyle(.insetGrouped)
         .appGroupedListBackground(container: PreferencesNavigationController.self)
+        .onTapGesture(count: 3) {
+            featureFlagName = ""
+            isShowingFeatureFlagAlert = true
+        }
+        .alert("Enable Feature Flag", isPresented: $isShowingFeatureFlagAlert) {
+            TextField("Name", text: $featureFlagName)
+                .textInputAutocapitalization(.never)
+                .autocorrectionDisabled()
+            
+            Button("Cancel", role: .cancel) {}
+            Button("Enable") {
+                if let flag = Preferences.FeatureFlag(rawValue: featureFlagName) {
+                    preferences.enabledFeatureFlags.insert(flag)
+                }
+            }
+        }
         .navigationBarTitle(Text("Advanced"))
     }
     
@@ -148,6 +168,31 @@ struct AdvancedPrefsView : View {
         }
     }
     
+    @ViewBuilder
+    var featureFlagSection: some View {
+        if !preferences.enabledFeatureFlags.isEmpty {
+            Section {
+                ForEach(preferences.enabledFeatureFlags.map(\.rawValue).sorted(), id: \.self) { name in
+                    Text(verbatim: name)
+                        .contextMenu {
+                            Button(role: .destructive) {
+                                preferences.enabledFeatureFlags.remove(.init(rawValue: name)!)
+                            } label: {
+                                Label("Remove", systemImage: "trash")
+                            }
+                        }
+                }
+                .onDelete { indices in
+                    let sortedFlags = preferences.enabledFeatureFlags.sorted(by: { $0.rawValue < $1.rawValue })
+                    let removed = indices.map { sortedFlags[$0] }
+                    preferences.enabledFeatureFlags.subtract(removed)
+                }
+            } header: {
+                Text("Feature Flags")
+            }
+        }
+    }
+    
     private func clearCache() {
         for account in UserAccountsManager.shared.accounts {
             let controller = MastodonController.getForAccount(account)