calling Roslyn from VSIX command

Question

What is best way to obtain Roslyn's SyntaxTree from EnvDTE.ProjectItem? I found some method for the other way (Roslyn's Document into ProjectItem).

I got VSIX command called from opened document and I'd like to experiment with Roslyn's syntax tree there.

This code works, but looks awkward to me:

    var pi = GetProjectItem();
    var piName = pi.get_FileNames(1);

    var componentModel = (IComponentModel)Microsoft.VisualStudio.Shell.Package.GetGlobalService(typeof(SComponentModel));
    var workspace = componentModel.GetService<Microsoft.VisualStudio.LanguageServices.VisualStudioWorkspace>();
    var ids = workspace.GetOpenDocumentIds();
    var id1 = ids.First(id => workspace.GetFilePath(id) == piName);

        Microsoft.CodeAnalysis.Solution sln = workspace.CurrentSolution;
        var doc = sln.GetDocument(id1);
        //var w = await doc.GetSyntaxTreeAsync();
        Microsoft.CodeAnalysis.SyntaxTree syntaxTree;
        if (doc.TryGetSyntaxTree(out syntaxTree))

Is there better way to get Roslyn's Document from active document?

Ricotta

Answer 1

You can use workspace.CurrentSolution.GetDocumentIdsWithFilePath() to get the DocumentId(s) matching a file path. From that you can get the document itself using workspace.CurrentSolution.GetDocument()

private Document GetActiveDocument()
{
    var dte = Package.GetGlobalService(typeof(DTE)) as DTE;
    var activeDocument = dte?.ActiveDocument;
    if (activeDocument == null) return null;

    var componentModel = (IComponentModel)Package.GetGlobalService(typeof(SComponentModel));
    var workspace = (Workspace) componentModel.GetService<VisualStudioWorkspace>();

    var documentid = workspace.CurrentSolution.GetDocumentIdsWithFilePath(activeDocument.FullName).FirstOrDefault();
    if (documentid == null) return null;

    return workspace.CurrentSolution.GetDocument(documentid);
}

Seeger

The .FirstOrDefault(); would not give you the document in the active context (in case of multi-target projects or shared projects). – Santana

Answer 2

Frank's answer works great. I found it hard to figure out what the type-names are, so here's Frank's code with fully qualified typenames:

using System.Linq;

var dte = Microsoft.VisualStudio.Shell.Package.GetGlobalService(typeof(EnvDTE.DTE)) as EnvDTE.DTE;
var activeDocument = dte?.ActiveDocument;
if (activeDocument != null)
{
    var componentModel = (Microsoft.VisualStudio.ComponentModelHost.IComponentModel)Microsoft.VisualStudio.Shell.Package.GetGlobalService(typeof(Microsoft.VisualStudio.ComponentModelHost.SComponentModel));
    var workspace = (Microsoft.CodeAnalysis.Workspace)componentModel.GetService<Microsoft.VisualStudio.LanguageServices.VisualStudioWorkspace>();
    var documentId = workspace.CurrentSolution.GetDocumentIdsWithFilePath(activeDocument.FullName).FirstOrDefault();
    if (documentId != null)
    {
        var document = workspace.CurrentSolution.GetDocument(documentId);
    }
}

And here are the references to find those types:

• nuget: Microsoft.VisualStudio.Shell.14.0
• nuget: Microsoft.CodeAnalysis
• nuget: Microsoft.VisualStudio.LanguageService
• framework: EnvDTE (version 8.0, and set Embed Interop Types to false)
• framework: Microsoft.VisualStudio.ComponentModelHost

I hope the two framework references can be replaced with NuGet references to VSSDK.DTE and VSSDK.ComponentModelHost, but when I tried, it gave build warnings about assembly version mismatches so I gave up.

Dolora

The .FirstOrDefault(); would not give you the document in the active context (in case of multi-target projects or shared projects). – Santana

Answer 3

If you can figure out how to get from a ProjectItem to an editor ITextSnapshot, then it would be better to use snapshot.AsText().GetOpenDocumentInCurrentContextWithChanges().

Note also that in your code above, by using TryGetSyntaxTree you are relying on someone else having requested the parse tree before you.

Poi

AsText extension method looks very useful. Unfortunatelly I didn't found a way to get that ITextSnapshot yet. Any clue? – Ricotta

found this link – Ricotta