Type storage: Fixed handling of namespaces that have sub-namespaces but do not directly contain classes.

ICSharpCode.NRefactory.Tests/CSharp/Resolver/NameLookupTests.cs

@@ -350,7 +350,7 @@ namespace Root.Child {
 			Assert.AreEqual("Root.Alpha", result.Type.FullName);
 		}
 		
-		[Test, Ignore("type references not implemented")]
+		[Test]
 		public void ImportAliasTest()
 		{
 			string program = @"using COL = System.Collections;
@@ -377,7 +377,7 @@ class TestClass {
 			Assert.AreEqual("System.Collections.Generic", ns.NamespaceName, "COL.Generic");
 		}
 		
-		[Test, Ignore("Cannot resolve type references")]
+		[Test]
 		public void ImportAliasClassResolveTest()
 		{
 			string program = @"using COL = System.Collections.ArrayList;
@@ -394,6 +394,35 @@ class TestClass {
 			Assert.AreEqual("System.Collections.ArrayList", rr.Type.FullName, "a");
 		}
 		
+		[Test]
+		public void ImportSubnamespaceWithAliasTest()
+		{
+			string program = @"namespace PC
+{
+	// Define an alias for the nested namespace.
+	using Project = PC.MyCompany.Project;
+	class A
+	{
+		Project.MyClass M()
+		{
+			// Use the alias
+			$Project.MyClass$ mc = new Project.MyClass();
+			return mc;
+		}
+	}
+	namespace MyCompany
+	{
+		namespace Project
+		{
+			public class MyClass { }
+		}
+	}
+}
+";
+			var mrr = Resolve(program);
+			Assert.AreEqual("PC.MyCompany.Project.MyClass", mrr.Type.FullName);
+		}
+		
 		[Test, Ignore("Parser position bug")]
 		public void ResolveNamespaceSD_863()
 		{

ICSharpCode.NRefactory/CSharp/Resolver/ResolveVisitor.cs

@@ -1078,11 +1078,13 @@ namespace ICSharpCode.NRefactory.CSharp.Resolver
 		#region Using Declaration
 		public override ResolveResult VisitUsingDeclaration(UsingDeclaration usingDeclaration, object data)
 		{
+			ScanChildren(usingDeclaration);
 			return null;
 		}
 		
 		public override ResolveResult VisitUsingAliasDeclaration(UsingAliasDeclaration usingDeclaration, object data)
 		{
+			ScanChildren(usingDeclaration);
 			return null;
 		}
 		#endregion

ICSharpCode.NRefactory/TypeSystem/Implementation/TypeStorage.cs

@@ -46,7 +46,7 @@ namespace ICSharpCode.NRefactory.TypeSystem.Implementation
 			
 			public bool Equals(FullNameAndTypeParameterCount x, FullNameAndTypeParameterCount y)
 			{
-				return x.TypeParameterCount == y.TypeParameterCount 
+				return x.TypeParameterCount == y.TypeParameterCount
 					&& NameComparer.Equals(x.Name, y.Name)
 					&& NameComparer.Equals(x.Namespace, y.Namespace);
 			}
@@ -110,11 +110,29 @@ namespace ICSharpCode.NRefactory.TypeSystem.Implementation
 		#region Namespace Storage
 		class NamespaceEntry
 		{
+			/// <summary>
+			/// Full namespace name
+			/// </summary>
 			public readonly string Name;
+			
+			/// <summary>
+			/// Parent namespace
+			/// </summary>
+			public readonly NamespaceEntry Parent;
+			
+			/// <summary>
+			/// Number of classes in this namespace (not in sub-namespaces)
+			/// </summary>
 			public int ClassCount;
 			
-			public NamespaceEntry(string name)
+			/// <summary>
+			/// Number of sub-namespaces.
+			/// </summary>
+			public int SubNamespaceCount;
+			
+			public NamespaceEntry(NamespaceEntry parent, string name)
 			{
+				this.Parent = parent;
 				this.Name = name;
 			}
 		}
@@ -145,9 +163,11 @@ namespace ICSharpCode.NRefactory.TypeSystem.Implementation
 				}
 				
 				// now create new dict
-				var newDict = _typeDicts[0].Values.GroupBy(c => c.Namespace, nameComparer)
-					.Select(g => new NamespaceEntry(g.Key) { ClassCount = g.Count() })
-					.ToDictionary(d => d.Name);
+				var newDict = new Dictionary<string, NamespaceEntry>(nameComparer);
+				foreach (ITypeDefinition type in _typeDicts[0].Values) {
+					NamespaceEntry ne = GetOrCreateNamespaceEntry(newDict, type.Namespace);
+					ne.ClassCount++;
+				}
 				
 				// add the new dict to the array of dicts
 				var newNamespaceDicts = new Dictionary<string, NamespaceEntry>[namespaceDicts.Length + 1];
@@ -157,6 +177,25 @@ namespace ICSharpCode.NRefactory.TypeSystem.Implementation
 				return newDict;
 			}
 		}
+		
+		NamespaceEntry GetOrCreateNamespaceEntry(Dictionary<string, NamespaceEntry> dict, string ns)
+		{
+			NamespaceEntry ne;
+			if (!dict.TryGetValue(ns, out ne)) {
+				NamespaceEntry parentEntry;
+				if (string.IsNullOrEmpty(ns)) {
+					parentEntry = null;
+				} else {
+					int pos = ns.LastIndexOf('.');
+					string parentNS = pos < 0 ? string.Empty : ns.Substring(0, pos);
+					parentEntry = GetOrCreateNamespaceEntry(dict, parentNS);
+					parentEntry.SubNamespaceCount++;
+				}
+				ne = new NamespaceEntry(parentEntry, ns);
+				dict.Add(ns, ne);
+			}
+			return ne;
+		}
 		#endregion
 		
 		#region ITypeResolveContext implementation
@@ -257,12 +296,23 @@ namespace ICSharpCode.NRefactory.TypeSystem.Implementation
 				foreach (var dict in _namespaceDicts) {
 					NamespaceEntry ns;
 					if (dict.TryGetValue(typeDefinition.Namespace, out ns)) {
-						if (--ns.ClassCount == 0)
-							dict.Remove(typeDefinition.Namespace);
+						ns.ClassCount--;
+						RemoveNamespaceIfPossible(dict, ns);
 					}
 				}
 			}
 		}
+		
+		void RemoveNamespaceIfPossible(Dictionary<string, NamespaceEntry> dict, NamespaceEntry ns)
+		{
+			while (ns.ClassCount == 0 && ns.SubNamespaceCount == 0) {
+				dict.Remove(ns.Name);
+				ns = ns.Parent;
+				if (ns == null)
+					break;
+				ns.SubNamespaceCount--;
+			}
+		}
 		#endregion
 		
 		#region UpdateType
@@ -281,12 +331,8 @@ namespace ICSharpCode.NRefactory.TypeSystem.Implementation
 			}
 			if (isNew) {
 				foreach (var dict in _namespaceDicts) {
-					NamespaceEntry ns;
-					if (dict.TryGetValue(typeDefinition.Namespace, out ns)) {
-						++ns.ClassCount;
-					} else {
-						dict.Add(typeDefinition.Namespace, new NamespaceEntry(typeDefinition.Namespace) { ClassCount = 1 });
-					}
+					NamespaceEntry ns = GetOrCreateNamespaceEntry(dict, typeDefinition.Namespace);
+					++ns.ClassCount;
 				}
 			}
 		}