Globbing is failing for root and/or same named nested directory

[matthid]

Description

This change should - in theory - be a noop. But it fixes invalid matches in the following glob:

    let dllsAndLibDirs (dllPattern:IGlobbingPattern) = 
        let dlls = 
            dllPattern
            |> Seq.distinctBy Path.GetFileName
            |> List.ofSeq
        let libDirs = 
            dlls
            |> Seq.map Path.GetDirectoryName
            |> Seq.distinct
            |> List.ofSeq
        (dlls,libDirs)      
    let fake5LegacyDlls, fake5LegacyLibDirs = 
        !! "./build/**/Fake.*.dll"
          ++ "./build/FakeLib.dll"
          -- "./build/**/Fake.Experimental.dll"
          -- "./build/**/FSharp.Compiler.Service.dll"
          -- "./build/**/netcore/FAKE.FSharp.Compiler.Service.dll"
          -- "./build/**/FAKE.FSharp.Compiler.Service.dll"
          -- "./build/**/Fake.IIS.dll"
          -- "./build/**/Fake.Deploy.Lib.dll"
        |> dllsAndLibDirs

This is on circle-ci where the repository is checked out at /build so there might be a conflict on /build/build here

Repro steps

1. Revert the change
2. Trigger a build on circle-ci

Expected behavior

Works, ie the glob should not match files in /build/test/

Actual behavior

Glob matches files it shouldn't match

Known workarounds

See the change

Related information

• Failed build: https://circleci.com/gh/fsharp/FAKE/302?utm_campaign=vcs-integration-link&utm_medium=referral&utm_source=github-build-link
• Working build: https://circleci.com/gh/fsharp/FAKE/303?utm_campaign=vcs-integration-link&utm_medium=referral&utm_source=github-build-link

I tried to follow the code and reproduce it in fsi (mono), however I failed. It might be some specific .net core behavior on unix.

[matthid]

With the recent globbing fixes I found this as well and it should be fixed with RC014