deleted project hierarchy leaked through VisualStudioProjectTracker

[lifengl]

Version Used: new version inserted into Dev 15 code

Steps to Reproduce:

1. Add a CPS barebone project to a solution
2. Delete the project
3. Ctrl-Alt-Shift-F12 couple times to force GC
4. Attach Windbg, check UnconfiguredProjectImpl instance in the memory, they should be released.

Expected Behavior:
no project object hold in the memory after it is deleted.

Actual Behavior:
leak through this chain:

-> 1c35480c Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem.DocumentKey
-> 1c24ffe8 Microsoft.VisualStudio.LanguageServices.CSharp.ProjectSystemShim.CSharpProjectShimWithServices
-> 1c1a0714 Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem.VisualStudioProjectTracker
-> 1c1a0808 System.Collections.Generic.List1[[Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem.VisualStudioProjectTracker+WorkspaceHostState, Microsoft.VisualStudio.LanguageServices]] -> 23833ad0 Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem.VisualStudioProjectTracker+WorkspaceHostState[] -> 1c1a0f78 Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem.VisualStudioProjectTracker+WorkspaceHostState -> 1c1a0f90 System.Collections.Generic.HashSet1[[Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem.AbstractProject, Microsoft.VisualStudio.LanguageServices]]
-> 1c262a80 System.Collections.Generic.HashSet`1+Slot[[Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem.AbstractProject, Microsoft.VisualStudio.LanguageServices]][]
-> 23c9829c Microsoft.VisualStudio.LanguageServices.CSharp.ProjectSystemShim.CSharpProjectShimWithServices
-> 23acc8d0 Microsoft.VisualStudio.ProjectSystem.VS.Implementation.Package.ProjectNode
-> 23aadeb8 Microsoft.VisualStudio.ProjectSystem.UnconfiguredProjectImpl

[Pilchie]

@lifengl: Does this repro with regular csproj as well? Is it possible that CPS isn't calling the same method on remove that we normally listen to in order to clean up projects (Mostly ICSharpProjectSite.Disconnect)?

[heejaechang]

adding another repro step. reported by @adriansecchia

Repro on Dev14 Update3

1.  New WPF C# project
   

2.  Close all documents, open App.xaml.cs
   

3.  Close VS
   

4.  Reopen VS with the project created in #1
   

5.  Touch project.csproj from the commandline
   

6.  Reload Project on the dialog that pops up in VS
   

7.  Repeat from #5
   

This leaks:

            ->  08b802f0 Microsoft.VisualStudio.LanguageServices.RoslynDocumentProvider
            ->  08b8032c System.Collections.Generic.Dictionary`2[[Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem.DocumentKey, Microsoft.VisualStudio.LanguageServices],[Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem.DocumentProvider+StandardTextDocument, Microsoft.VisualStudio.LanguageServices]]
            ->  08d61068 System.Collections.Generic.Dictionary`2+Entry[[Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem.DocumentKey, Microsoft.VisualStudio.LanguageServices],[Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem.DocumentProvider+StandardTextDocument, Microsoft.VisualStudio.LanguageServices]][]
            ->  124511b4 Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem.DocumentKey
            ->  12435eb4 Microsoft.VisualStudio.LanguageServices.CSharp.ProjectSystemShim.CSharpProjectShimWithServices
            ->  08b801d4 Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem.VisualStudioProjectTracker
            ->  08b802c8 System.Collections.Generic.List`1[[Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem.VisualStudioProjectTracker+WorkspaceHostState, Microsoft.VisualStudio.LanguageServices]]
            ->  08b802e0 Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem.VisualStudioProjectTracker+WorkspaceHostState[]
            ->  08b80ab8 Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem.VisualStudioProjectTracker+WorkspaceHostState
            ->  08b80ad0 System.Collections.Generic.HashSet`1[[Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem.AbstractProject, Microsoft.VisualStudio.LanguageServices]]
            ->  123c7898 System.Collections.Generic.HashSet`1+Slot[[Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem.AbstractProject, Microsoft.VisualStudio.LanguageServices]][]
            ->  123e92cc Microsoft.VisualStudio.LanguageServices.CSharp.ProjectSystemShim.CSharpProjectShimWithServices

The CSharpProjectShimWithServices grows by 1 each iteration. There is only 1 VisualStudioProjectTracker+WorkspaceHostState

[heejaechang]

link to specific customer comments #7082 (comment)

[davidroth]

@jasonmalinowski As written in #7082 , it would be great if this could also be fixed in roslyn 1.4 (VS2015) because I think this is the reason I still have to restart VS some times a day because of excessive memory usage due to git branch switching or git rebasing.