Support not running secrets analysis on .gitignore-d files

[rita-gorokhod]

Description

In other SLVS flavors, the rules are run on text files, unless they are explicitly excluded by being in the .gitignore file i.e. if a project is not under source control then issues will be reported.

This behaviour is nice-to-have; if we can do it easily, great, otherwise it is ok only to run secrets rules for for files we know are under source control.

[duncanp-lseg]

Notes:

EnvDTE.SourceControl::IsItemUnderSCC(filePath)

Pros:

• public VS interface, VS2015+
• should work for multiple source control systems

Cons:

• limited: doesn't differentiate between (1) ignored files and (2) new files that have been created but not staged or committed:

XXX File: D:\proto\SLVS\SCCDetection\SampleApp\.gitignore
	underSCC: True, 	checkedOut: False

XXX File: D:\proto\SLVS\SCCDetection\SampleApp\SampleApp.csproj
	underSCC: True, 	checkedOut: False

XXX File: D:\proto\SLVS\SCCDetection\SampleApp\Program.cs
	underSCC: True, 	checkedOut: False

XXX File: D:\proto\SLVS\SCCDetection\SampleApp\IgnoredFile.txt
	underSCC: False, 	checkedOut: False

XXX File: D:\proto\SLVS\SCCDetection\SampleApp\ExistingFile_Committed.txt
	underSCC: True, 	checkedOut: False

XXX File: D:\proto\SLVS\SCCDetection\SampleApp\ExistingFile_ModifiedLocally.txt
	underSCC: True, 	checkedOut: True

XXX File: D:\proto\SLVS\SCCDetection\SampleApp\NewFile_AddedButNotCommitted.txt
	underSCC: False, 	checkedOut: False

XXX File: D:\proto\SLVS\SCCDetection\SampleApp\NewFile_StagedButNotCommitted.txt
	underSCC: True, 	checkedOut: True

XXX File: D:\proto\SLVS\SCCDetection\SampleApp\MISSING_FILE.txt
	underSCC: True, 	checkedOut: False

LibGit2Sharp

NuGet: https://www.nuget.org/packages/LibGit2Sharp/0.27.0-preview-0119

Cons:

• Git-only
• public NuGet package is v0.26.2
• adds approx 6MB to the VSIX (less if we exclude the Mac/Unix libraries, but that would be more complicated)

Pros:

• correctly detects whether files are ignored or not
• widely used (4.5 million downloads)
• VS ships with a privately-built version
• ?used in the GitHub extension for VS?

var startPath = ...
var repoPath = Repository.Discover(startPath);

using (var repo = new Repository(repoPath))
{
    // NOTE: needs a relative file path with Unix directory separators
    var isIgnored = repo.Ignore.IsPathIgnored(file);
    Debug.WriteLine($"YYY IsIgnored: {isIgnored}, file: {file}");
}

[rita-gorokhod]

Notes:

The following works for non open-as-folder projects:

            var projectHierarchy = GetVsHierarchyForFile(fullFilePath);
            var itemId = FindProjectItemId(projectHierarchy, fullFilePath);
            var hr = projectHierarchy.GetProperty(itemId, (int)__VSHPROPID.VSHPROPID_StateIconIndex, out var stateIcon);

stateIcon is of type VsStateIcon and the sample app returns the following values:

ExistingFile_Committed -- STATEICON_CHECKEDIN ExistingFile_ModifiedLocally -- STATEICON_CHECKEDOUT IgnoredFile -- STATEICON_EXCLUDEDFROMSCC NewFile_AddedButNotCommitted -- STATEICON_MAXINDEX NewFile_StagedButNotCommitted -- STATEICON_MAXINDEX

Unfortunately, for open-as-folder projects, stateIcon is null. I've attempted to retrieve projectHierarchy in other ways, i.e. by enumerating IVsSolution projects, in which case I can get ProjectItem of the file; in the debugger I can see ProjectItem.Properties.Node.StateIconIndex -- but I cannot retrieve it at runtime as those are internal VS properties.