Merge pull request #3039 from unoplatform/dev/jela/mvux-hr

fix(feeds): Don't use delegates as key for instance caching

Author: jeromelaban

src/Uno.Extensions.Reactive/Core/ListState.T.cs

@@ -64,23 +64,36 @@ public static IListState<T> Empty<TOwner>(TOwner owner, [CallerMemberName] strin
 	/// <typeparam name="TOwner">Type of the owner of the state.</typeparam>
 	/// <param name="owner">The owner of the state.</param>
 	/// <param name="valueProvider">The provider of the initial value of the state.</param>
+	/// <param name="name">The caller member name, used as a stable cache key.</param>
+	/// <param name="line">The caller line number, used as a stable cache key.</param>
 	/// <returns>A feed that encapsulate the source.</returns>
-	public static IListState<T> Value<TOwner>(TOwner owner, Func<IImmutableList<T>> valueProvider)
+	public static IListState<T> Value<TOwner>(TOwner owner, Func<IImmutableList<T>> valueProvider, [CallerMemberName] string? name = null, [CallerLineNumber] int line = -1)
 		where TOwner : class
-		// Note: We force the usage of delegate so 2 properties which are doing State.Value(this, () => 42) will effectively have 2 distinct states.
-		=> AttachedProperty.GetOrCreate(owner, valueProvider, static (o, v) => SourceContext.GetOrCreate(o).CreateListState(Option<IImmutableList<T>>.Some(v())));
+		// Use CallerMemberName+line as stable cache key instead of delegate reference identity.
+		// Delegate instances can be recreated after MetadataUpdater.ApplyUpdate on WASM,
+		// which would cause cache misses and state recreation (spec 033).
+		=> AttachedProperty.GetOrCreate<TOwner, (string, int), Func<IImmutableList<T>>, IListState<T>>(
+			owner,
+			(name ?? throw new InvalidOperationException("The name of the list state must not be null"), line < 0 ? throw new InvalidOperationException("The provided line number is invalid.") : line),
+			valueProvider,
+			static (o, _, v) => SourceContext.GetOrCreate(o).CreateListState(Option<IImmutableList<T>>.Some(v())));
 
 	/// <summary>
 	/// Gets or creates a list state from a static initial list of items.
 	/// </summary>
 	/// <typeparam name="TOwner">Type of the owner of the state.</typeparam>
 	/// <param name="owner">The owner of the state.</param>
 	/// <param name="valueProvider">The provider of the initial value of the state.</param>
+	/// <param name="name">The caller member name, used as a stable cache key.</param>
+	/// <param name="line">The caller line number, used as a stable cache key.</param>
 	/// <returns>A feed that encapsulate the source.</returns>
-	public static IListState<T> Value<TOwner>(TOwner owner, Func<ImmutableList<T>> valueProvider)
+	public static IListState<T> Value<TOwner>(TOwner owner, Func<ImmutableList<T>> valueProvider, [CallerMemberName] string? name = null, [CallerLineNumber] int line = -1)
 		where TOwner : class
-		// Note: We force the usage of delegate so 2 properties which are doing State.Value(this, () => 42) will effectively have 2 distinct states.
-		=> AttachedProperty.GetOrCreate(owner, valueProvider, static (o, v) => SourceContext.GetOrCreate(o).CreateListState(Option<IImmutableList<T>>.Some(v())));
+		=> AttachedProperty.GetOrCreate<TOwner, (string, int), Func<ImmutableList<T>>, IListState<T>>(
+			owner,
+			(name ?? throw new InvalidOperationException("The name of the list state must not be null"), line < 0 ? throw new InvalidOperationException("The provided line number is invalid.") : line),
+			valueProvider,
+			static (o, _, v) => SourceContext.GetOrCreate(o).CreateListState(Option<IImmutableList<T>>.Some(v())));
 
 	/// <summary>
 	/// Gets or creates a list state from a static initial list of items.

src/Uno.Extensions.Reactive/Core/ListState.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Linq;
+using System.Runtime.CompilerServices;
 using System.Threading;
 
 namespace Uno.Extensions.Reactive;
@@ -34,11 +35,12 @@ public static IListState<TValue> Create<TOwner, TValue>(TOwner owner, Func<Cance
 	/// <typeparam name="TValue">The type of the value of the resulting feed.</typeparam>
 	/// <param name="owner">The owner of the state.</param>
 	/// <param name="valueProvider">The provider of the initial value of the state.</param>
+	/// <param name="name">The caller member name, used as a stable cache key.</param>
+	/// <param name="line">The caller line number, used as a stable cache key.</param>
 	/// <returns>A state that encapsulate the source.</returns>
-	public static IListState<TValue> Value<TOwner, TValue>(TOwner owner, Func<IImmutableList<TValue>> valueProvider)
+	public static IListState<TValue> Value<TOwner, TValue>(TOwner owner, Func<IImmutableList<TValue>> valueProvider, [CallerMemberName] string? name = null, [CallerLineNumber] int line = -1)
 		where TOwner : class
-	// Note: We force the usage of delegate so 2 properties which are doing State.Value(this, () => 42) will effectively have 2 distinct states.
-		=> ListState<TValue>.Value(owner, valueProvider);
+		=> ListState<TValue>.Value(owner, valueProvider, name, line);
 
 	/// <summary>
 	/// Gets or creates a list state from a static initial list of items.
@@ -47,11 +49,12 @@ public static IListState<TValue> Value<TOwner, TValue>(TOwner owner, Func<IImmut
 	/// <typeparam name="TValue">The type of the value of the resulting feed.</typeparam>
 	/// <param name="owner">The owner of the state.</param>
 	/// <param name="valueProvider">The provider of the initial value of the state.</param>
+	/// <param name="name">The caller member name, used as a stable cache key.</param>
+	/// <param name="line">The caller line number, used as a stable cache key.</param>
 	/// <returns>A state that encapsulate the source.</returns>
-	public static IListState<TValue> Value<TOwner, TValue>(TOwner owner, Func<ImmutableList<TValue>> valueProvider)
+	public static IListState<TValue> Value<TOwner, TValue>(TOwner owner, Func<ImmutableList<TValue>> valueProvider, [CallerMemberName] string? name = null, [CallerLineNumber] int line = -1)
 		where TOwner : class
-	// Note: We force the usage of delegate so 2 properties which are doing State.Value(this, () => 42) will effectively have 2 distinct states.
-		=> ListState<TValue>.Value(owner, valueProvider);
+		=> ListState<TValue>.Value(owner, valueProvider, name, line);
 
 	/// <summary>
 	/// Gets or creates a list state from an async method.