Support completion of unimported types.

[333fred]

This needs to call a few internal overloads for completion, instead of the public versions, in order to determine whether any completions can be expanded (ie, imported) and to get the full change for these items, including the import. The public APIs do not provide this information currently.

Todo:

• More testing!
• Make import completion optional. In large solutions it will almost certainly be expensive, we should provide an option to turn it off.

Preview of the change in vscode (watch the line numbers!):

Fixes #1482

[filipw]

it looks like the tests are a bit unstable for example this failed on Linux

    OmniSharp.Roslyn.CSharp.Tests.CompletionFacts.ImportCompletionResolvesOnSubsequentQueries(filename: "dummy.cs") [FAIL]
      System.OperationCanceledException : The operation was canceled.
      Stack Trace:
          at System.Threading.CancellationToken.ThrowOperationCanceledException () [0x00010] in <a17fa1457c5d44f2885ac746c1764ea5>:0 
          at System.Threading.CancellationToken.ThrowIfCancellationRequested () [0x00008] in <a17fa1457c5d44f2885ac746c1764ea5>:0 
          at OmniSharp.Roslyn.CSharp.Tests.CompletionFacts+<>c__DisplayClass9_0.<ImportCompletionResolvesOnSubsequentQueries>b__1 () [0x000d2] in <720a8e872b3940aca18dd68ab266aa89>:0 
          at OmniSharp.Roslyn.CSharp.Tests.CompletionFacts.ImportCompletionResolvesOnSubsequentQueries (System.String filename) [0x001ee] in <720a8e872b3940aca18dd68ab266aa89>:0 

but passed on a retry. Maybe some sort of a thread exhaustion, these agents are not too powerful

[filipw]

[333fred]

I'll up the cancelation limit. 100 ms is very stable locally, but I was a bit curious how they'd do on CI.

[333fred]

I'll up the cancelation limit. 100 ms is very stable locally, but I was a bit curious how they'd do on CI.

@filipw upped the timeout to a second/test.

[filipw]

thanks this is good to go IMHO! 🍻

[JoeRobich]

Thanks Fred!