Ignore directory name casing in EnvDTE.ProjectItems.

src/AddIns/Misc/PackageManagement/Project/Src/EnvDTE/ChildProjectItems.cs

@@ -62,7 +62,7 @@ namespace ICSharpCode.PackageManagement.EnvDTE
 		
 		bool SeenChildProjectItemBefore(ProjectItem childProjectItem)
 		{
-			if (ProjectItems.Any(item => item.Name == childProjectItem.Name)) {
+			if (ProjectItems.Any(item => item.IsMatchByName(childProjectItem.Name))) {
 				return true;
 			}
 			ProjectItems.Add(childProjectItem);

src/AddIns/Misc/PackageManagement/Test/Src/EnvDTE/ProjectItemsTests.cs

@@ -779,5 +779,21 @@ namespace PackageManagement.Tests.EnvDTE
 			Assert.AreEqual(1, childItems.Count);
 			Assert.AreEqual("duplicate.cs", duplicateFileItem.Name);
 		}
+		
+		[Test]
+		public void GetEnumerator_ProjectHasTwoFilesInFolderTwoLevelsDeepButParentFolderHasDifferentCase_TopLevelFolderOnlyHasOneProjectItemForChildFolder()
+		{
+			CreateProjectItems();
+			msbuildProject.FileName = @"d:\projects\MyProject\MyProject.csproj";
+			msbuildProject.AddFile(@"CodeTemplates\Scaffolders\File1.cs");
+			msbuildProject.AddFile(@"CodeTemplates\SCAFFOLDERS\File2.cs");
+			
+			DTE.ProjectItem codeTemplatesFolderItem = GetChildItem(projectItems, "CodeTemplates");
+			List<DTE.ProjectItem> childItems = GetAllChildItems(codeTemplatesFolderItem.ProjectItems);
+			DTE.ProjectItem scaffoldersFolderItem = childItems.FirstOrDefault();
+			
+			Assert.AreEqual(1, childItems.Count);
+			Assert.AreEqual("Scaffolders", scaffoldersFolderItem.Name);
+		}
 	}
 }