Correct regex completion

[333fred]

Depending on whether the context is a verbatim string or not, the regex provider will escape the text, so we need to realize it ahead of time. Fixes #1949.

[filipw]

ai, good catch

[333fred]

@filipw do you have any idea what could cause projects not be found on the Mac and Linux test legs? It seems that both the Mac and Linux MSBuild tests are seeing something like:

        [dbug]: OmniSharp.MSBuild.ProjectSystem
                Could not locate project for '/home/vsts/work/1/s/bin/Debug/OmniSharp.Roslyn.CSharp.Tests/net472/project.csproj'
        [dbug]: OmniSharp.MSBuild.ProjectSystem
                Could not locate project for 'dummy.csx'
        [dbug]: OmniSharp.Script.ScriptProjectSystem
                Could not locate project for 'dummy.csx'
        [trce]: OmniSharp.Roslyn.CSharp.Services.Completion.CompletionService
                Completions requested
        [trce]: OmniSharp.Roslyn.CSharp.Services.Completion.CompletionService
                Found 0 completions for dummy.csx:6,2

I'm especially confused because I'm doing nothing different in these tests than I'm doing for the other tests in the file, but these both are failing to locate projects.

[filipw]

yes I saw this before here 56afd27

at the time I just thought it was flaky and ended up removing it. Now it looks to me that CSX project system with project per CSX file somehow fails with the embedded language provider with Regex on *nix. I think it's OK to run these tests for *.cs only for now and we can investigate separately - at the end there is no regression here, it was just not being observed

[333fred]

I think it's OK to run these tests for *.cs only for now and we can investigate separately - at the end there is no regression here, it was just not being observed

Actually, these tests fail for .cs files as well.

[filipw]

hmm yes you are right. I would imagine we could repro this on a simple console project on Mono - perhaps it's a Roslyn bug?
either way, there is no regression here so adding [ConditionalFact(typeof(WindowsOnly))] would restrict it to Windows only for the time being. it shouldn't hold up this PR IMHO

[333fred]

Agreed, and done.

[filipw]

thanks a lot