Change Current property to handle nulls with exceptiion. Current must…

… never be null.

castleproject#563

src/Castle.Windsor.Extensions.DependencyInjection/Scope/ExtensionContainerRootScopeAccessor.cs

@@ -23,7 +23,7 @@ internal class ExtensionContainerRootScopeAccessor : IScopeAccessor
 	{
 		public ILifetimeScope GetScope(CreationContext context)
 		{
-			return ExtensionContainerScope.Current?.RootScope ?? throw new InvalidOperationException("No root scope");
+			return ExtensionContainerScope.CurrentOrThrow.RootScope ?? throw new InvalidOperationException("No root scope");
 		}
 
 		public void Dispose()

src/Castle.Windsor.Extensions.DependencyInjection/Scope/ExtensionContainerScope.cs

@@ -23,13 +23,13 @@ namespace Castle.Windsor.Extensions.DependencyInjection.Scope
 
 	internal class ExtensionContainerScope : ILifetimeScope, IDisposable
 	{
-		internal static ExtensionContainerScope Current
+		internal static ExtensionContainerScope CurrentOrThrow
 		{
-			get => current.Value;
+			get => current.Value ??  throw new InvalidOperationException("No scope available");
 			set => current.Value = value;
 		}
 		public static string TransientMarker = "Transient";
-		protected static readonly AsyncLocal<ExtensionContainerScope> current  = new AsyncLocal<ExtensionContainerScope>();
+		protected static readonly AsyncLocal<ExtensionContainerScope> current = new AsyncLocal<ExtensionContainerScope>();
 		private readonly ExtensionContainerScope parent;
 		private readonly IScopeCache scopeCache;
 
@@ -44,8 +44,7 @@ protected ExtensionContainerScope(ExtensionContainerScope parent, ExtensionConta
 
 		internal static ExtensionContainerScope BeginScope()
 		{
-			var parent = Current;
-			if (parent == null) throw new ArgumentNullException($"There is no parent scope to allow for BeginScope");
+			var parent = CurrentOrThrow;
 			var scope = new ExtensionContainerScope(parent, parent.RootScope);
 			current.Value = scope;
 			return scope;

src/Castle.Windsor.Extensions.DependencyInjection/Scope/ExtensionContainerScopeAccessor.cs

@@ -23,7 +23,7 @@ internal class ExtensionContainerScopeAccessor : IScopeAccessor
 	{
 		public ILifetimeScope GetScope(CreationContext context)
 		{
-			return ExtensionContainerScope.Current ??  throw new InvalidOperationException("No scope available");
+			return ExtensionContainerScope.CurrentOrThrow ?? throw new InvalidOperationException("No scope available");
 		}
 
 		public void Dispose()

src/Castle.Windsor.Extensions.DependencyInjection/Scope/ForcedScope.cs

@@ -24,12 +24,12 @@ internal class ForcedScope : IDisposable
 		private readonly ExtensionContainerScope previousScope;
 		internal ForcedScope(ExtensionContainerScope scope)
 		{
-			previousScope = ExtensionContainerScope.Current;
-			ExtensionContainerScope.Current = scope;
+			previousScope = ExtensionContainerScope.CurrentOrThrow;
+			ExtensionContainerScope.CurrentOrThrow = scope;
 		}
 		public void Dispose()
 		{
-			ExtensionContainerScope.Current = previousScope;
+			ExtensionContainerScope.CurrentOrThrow = previousScope;
 		}
 	}
 }