Merge pull request #954 from arkivanov/duplicate-configurations-stable

Promoted duplicate configurations feature to stable

Author: arkivanov

decompose/api/android/decompose.api

@@ -66,6 +66,25 @@ public final class com/arkivanov/decompose/DecomposeExperimentFlags {
 	public final fun setDuplicateConfigurationsEnabled (Z)V
 }
 
+public final class com/arkivanov/decompose/DecomposeSettings {
+	public static final field Companion Lcom/arkivanov/decompose/DecomposeSettings$Companion;
+	public fun <init> ()V
+	public fun <init> (Z)V
+	public synthetic fun <init> (ZILkotlin/jvm/internal/DefaultConstructorMarker;)V
+	public final fun component1 ()Z
+	public final fun copy (Z)Lcom/arkivanov/decompose/DecomposeSettings;
+	public static synthetic fun copy$default (Lcom/arkivanov/decompose/DecomposeSettings;ZILjava/lang/Object;)Lcom/arkivanov/decompose/DecomposeSettings;
+	public fun equals (Ljava/lang/Object;)Z
+	public final fun getDuplicateConfigurationsEnabled ()Z
+	public fun hashCode ()I
+	public fun toString ()Ljava/lang/String;
+}
+
+public final class com/arkivanov/decompose/DecomposeSettings$Companion {
+	public final fun getSettings ()Lcom/arkivanov/decompose/DecomposeSettings;
+	public final fun setSettings (Lcom/arkivanov/decompose/DecomposeSettings;)V
+}
+
 public final class com/arkivanov/decompose/DeeplinkUtilsKt {
 	public static final fun handleDeepLink (Landroid/app/Activity;Lkotlin/jvm/functions/Function1;)Ljava/lang/Object;
 }

decompose/api/decompose.klib.api

@@ -482,6 +482,25 @@ final class <#A: out kotlin/Any> com.arkivanov.decompose.router.pages/Pages { //
     }
 }
 
+final class com.arkivanov.decompose/DecomposeSettings { // com.arkivanov.decompose/DecomposeSettings|null[0]
+    constructor <init>(kotlin/Boolean = ...) // com.arkivanov.decompose/DecomposeSettings.<init>|<init>(kotlin.Boolean){}[0]
+
+    final val duplicateConfigurationsEnabled // com.arkivanov.decompose/DecomposeSettings.duplicateConfigurationsEnabled|{}duplicateConfigurationsEnabled[0]
+        final fun <get-duplicateConfigurationsEnabled>(): kotlin/Boolean // com.arkivanov.decompose/DecomposeSettings.duplicateConfigurationsEnabled.<get-duplicateConfigurationsEnabled>|<get-duplicateConfigurationsEnabled>(){}[0]
+
+    final fun component1(): kotlin/Boolean // com.arkivanov.decompose/DecomposeSettings.component1|component1(){}[0]
+    final fun copy(kotlin/Boolean = ...): com.arkivanov.decompose/DecomposeSettings // com.arkivanov.decompose/DecomposeSettings.copy|copy(kotlin.Boolean){}[0]
+    final fun equals(kotlin/Any?): kotlin/Boolean // com.arkivanov.decompose/DecomposeSettings.equals|equals(kotlin.Any?){}[0]
+    final fun hashCode(): kotlin/Int // com.arkivanov.decompose/DecomposeSettings.hashCode|hashCode(){}[0]
+    final fun toString(): kotlin/String // com.arkivanov.decompose/DecomposeSettings.toString|toString(){}[0]
+
+    final object Companion { // com.arkivanov.decompose/DecomposeSettings.Companion|null[0]
+        final var settings // com.arkivanov.decompose/DecomposeSettings.Companion.settings|{}settings[0]
+            final fun <get-settings>(): com.arkivanov.decompose/DecomposeSettings // com.arkivanov.decompose/DecomposeSettings.Companion.settings.<get-settings>|<get-settings>(){}[0]
+            final fun <set-settings>(com.arkivanov.decompose/DecomposeSettings) // com.arkivanov.decompose/DecomposeSettings.Companion.settings.<set-settings>|<set-settings>(com.arkivanov.decompose.DecomposeSettings){}[0]
+    }
+}
+
 final class com.arkivanov.decompose/DefaultComponentContext : com.arkivanov.decompose/ComponentContext { // com.arkivanov.decompose/DefaultComponentContext|null[0]
     constructor <init>(com.arkivanov.essenty.lifecycle/Lifecycle) // com.arkivanov.decompose/DefaultComponentContext.<init>|<init>(com.arkivanov.essenty.lifecycle.Lifecycle){}[0]
     constructor <init>(com.arkivanov.essenty.lifecycle/Lifecycle, com.arkivanov.essenty.statekeeper/StateKeeper? = ..., com.arkivanov.essenty.instancekeeper/InstanceKeeper? = ..., com.arkivanov.essenty.backhandler/BackHandler? = ...) // com.arkivanov.decompose/DefaultComponentContext.<init>|<init>(com.arkivanov.essenty.lifecycle.Lifecycle;com.arkivanov.essenty.statekeeper.StateKeeper?;com.arkivanov.essenty.instancekeeper.InstanceKeeper?;com.arkivanov.essenty.backhandler.BackHandler?){}[0]

decompose/api/jvm/decompose.api

@@ -66,6 +66,25 @@ public final class com/arkivanov/decompose/DecomposeExperimentFlags {
 	public final fun setDuplicateConfigurationsEnabled (Z)V
 }
 
+public final class com/arkivanov/decompose/DecomposeSettings {
+	public static final field Companion Lcom/arkivanov/decompose/DecomposeSettings$Companion;
+	public fun <init> ()V
+	public fun <init> (Z)V
+	public synthetic fun <init> (ZILkotlin/jvm/internal/DefaultConstructorMarker;)V
+	public final fun component1 ()Z
+	public final fun copy (Z)Lcom/arkivanov/decompose/DecomposeSettings;
+	public static synthetic fun copy$default (Lcom/arkivanov/decompose/DecomposeSettings;ZILjava/lang/Object;)Lcom/arkivanov/decompose/DecomposeSettings;
+	public fun equals (Ljava/lang/Object;)Z
+	public final fun getDuplicateConfigurationsEnabled ()Z
+	public fun hashCode ()I
+	public fun toString ()Ljava/lang/String;
+}
+
+public final class com/arkivanov/decompose/DecomposeSettings$Companion {
+	public final fun getSettings ()Lcom/arkivanov/decompose/DecomposeSettings;
+	public final fun setSettings (Lcom/arkivanov/decompose/DecomposeSettings;)V
+}
+
 public final class com/arkivanov/decompose/DefaultComponentContext : com/arkivanov/decompose/ComponentContext {
 	public fun <init> (Lcom/arkivanov/essenty/lifecycle/Lifecycle;)V
 	public fun <init> (Lcom/arkivanov/essenty/lifecycle/Lifecycle;Lcom/arkivanov/essenty/statekeeper/StateKeeper;Lcom/arkivanov/essenty/instancekeeper/InstanceKeeper;Lcom/arkivanov/essenty/backhandler/BackHandler;)V

decompose/src/commonMain/kotlin/com/arkivanov/decompose/DecomposeExperimentFlags.kt

@@ -3,5 +3,12 @@ package com.arkivanov.decompose
 @ExperimentalDecomposeApi
 object DecomposeExperimentFlags {
 
-    var duplicateConfigurationsEnabled: Boolean = false
+    @Deprecated(
+        message = "The feature has been promoted to stable. Please use DecomposeSettings.duplicateConfigurationsEnabled instead.",
+    )
+    var duplicateConfigurationsEnabled: Boolean
+        get() = DecomposeSettings.settings.duplicateConfigurationsEnabled
+        set(value) {
+            DecomposeSettings.settings = DecomposeSettings.settings.copy(duplicateConfigurationsEnabled = value)
+        }
 }

decompose/src/commonMain/kotlin/com/arkivanov/decompose/DecomposeSettings.kt

@@ -0,0 +1,19 @@
+package com.arkivanov.decompose
+
+import kotlin.concurrent.Volatile
+
+/**
+ * Global Decompose settings. Use [DecomposeSettings.settings] property to change the settings.
+ *
+ * @param duplicateConfigurationsEnabled controls whether duplicate configurations are enabled or not. Default value is `false`.
+ * Excludes the `Child Items` navigation model, which doesn't support duplicate configurations.
+ */
+data class DecomposeSettings(
+    val duplicateConfigurationsEnabled: Boolean = false,
+) {
+
+    companion object {
+        @Volatile
+        var settings: DecomposeSettings = DecomposeSettings()
+    }
+}

decompose/src/commonMain/kotlin/com/arkivanov/decompose/Utils.kt

@@ -15,17 +15,22 @@ internal expect val KClass<*>.uniqueName: String?
 
 internal val Lifecycle.isDestroyed: Boolean get() = state == Lifecycle.State.DESTROYED
 
-internal fun <T : Any, C : Any> List<T>.keyed(configuration: (T) -> C): Map<Any, T> {
-    val numbers = HashMap<C, Int>()
+internal fun <T : Any, C : Any> List<T>.keyed(configuration: (T) -> C): Map<ItemKey, T> {
+    val indices = HashMap<C, Int>()
 
     return associateBy { item ->
         val config = configuration(item)
-        val number = (numbers[config] ?: 0) + 1
-        numbers[config] = number
-        config to number
+        val index = indices[config]?.plus(1) ?: 0
+        indices[config] = index
+        ItemKey(config, index)
     }
 }
 
+internal data class ItemKey(
+    private val value: Any,
+    private val index: Int,
+)
+
 internal fun <T : Any> Iterable<T>.findFirstDuplicate(set: Set<T>): Pair<Int, T>? {
     val iter1 = iterator()
     val iter2 = set.iterator()

decompose/src/commonMain/kotlin/com/arkivanov/decompose/router/children/ChildItem.kt

@@ -10,20 +10,28 @@ internal sealed interface ChildItem<out C : Any, out T : Any> {
 
     val configuration: C
     val instance: T?
+    val lifecycleRegistry: LifecycleRegistry?
+    val stateKeeperDispatcher: StateKeeperDispatcher?
+    val instanceKeeperDispatcher: InstanceKeeperDispatcher?
+    val backHandler: ChildBackHandler?
 
     data class Created<out C : Any, out T : Any>(
         override val configuration: C,
         override val instance: T,
-        val lifecycleRegistry: LifecycleRegistry,
-        val stateKeeperDispatcher: StateKeeperDispatcher,
-        val instanceKeeperDispatcher: InstanceKeeperDispatcher,
-        val backHandler: ChildBackHandler,
+        override val lifecycleRegistry: LifecycleRegistry,
+        override val stateKeeperDispatcher: StateKeeperDispatcher,
+        override val instanceKeeperDispatcher: InstanceKeeperDispatcher,
+        override val backHandler: ChildBackHandler,
     ) : ChildItem<C, T>
 
     data class Destroyed<out C : Any>(
         override val configuration: C,
         val savedState: SerializableContainer? = null
     ) : ChildItem<C, Nothing> {
         override val instance: Nothing? = null
+        override val lifecycleRegistry: LifecycleRegistry? = null
+        override val stateKeeperDispatcher: StateKeeperDispatcher? = null
+        override val instanceKeeperDispatcher: InstanceKeeperDispatcher? = null
+        override val backHandler: ChildBackHandler? = null
     }
 }

decompose/src/commonMain/kotlin/com/arkivanov/decompose/router/children/ChildrenFactory.kt

@@ -69,8 +69,12 @@ fun <Ctx : GenericComponentContext<Ctx>, C : Any, T : Any, E : Any, N : NavState
  * The API is based around [NavState] and [ChildNavState] interfaces that should be implemented by
  * clients. [NavState] represents a persistent state of the navigation. It also holds a navigation
  * state for each child - [ChildNavState]. Both [NavState] and [ChildNavState] must be immutable, and
- * correctly implement `equals` and `hashCode` methods (or just be data classes). There must be no
- * duplicated (by equality) [ChildNavState.configuration] within a [NavState].
+ * correctly implement `equals` and `hashCode` methods (or just be data classes).
+ *
+ * By default, having duplicate (by equality) configurations ([ChildNavState.configuration]) within
+ * a [NavState] is prohibited. Decompose will throw an exception when detected. However, duplicate
+ * configurations can be enabled by setting the
+ * [com.arkivanov.decompose.DecomposeSettings.duplicateConfigurationsEnabled] flag to `true`.
  *
  * The navigation is performed by transforming the current [NavState] to a new one. The implementation
  * calculates diffs between the old list of [ChildNavState] and the new one, and manipulates child