FAKE 5, expecto helper always runs mono/process

[haf]

Example:

let testNetCoreDir = "src" </> "Suave.Tests" </> "bin" </> "Release" </> "netcoreapp2.0"

Target.create "Test" <| fun _ ->
  Expecto.run id (!! (testNetCoreDir </> "Suave.Tests.dll"))

Crashes:

Starting task 'Expecto': /suave/src/Suave.Tests/bin/Release/netcoreapp2.0/Suave.Tests.dll
/suave/src/Suave.Tests/bin/Release/netcoreapp2.0/Suave.Tests.dll --parallel --parallel-workers 0 --fail-on-focused-tests --version
Finished 'Expecto' in 00:00:00.0211410
Finished 'Test' in 00:00:00.0255590

---------------------------------------------------------------------
Build Time Report
---------------------------------------------------------------------
Target     Duration
------     --------
Clean      00:00:00.1491990
Restore    00:00:11.4618120
AsmInfo    00:00:00.2100470
Replace    00:00:00.0002830
Build      00:00:47.5418750
Test       00:00:00.0254760   (Start of process /suave/src/Suave.Tests/bin/Release/netcoreapp2.0/Suave.Tests.dll failed.)
Total:     00:00:59.4403840
Status:    Failure
---------------------------------------------------------------------
-> BuildFailedException: Target 'Test' failed.
-> One or more errors occurred. (Start of process /Users/h/dev/logibit/suave/src/Suave.Tests/bin/Release/netcoreapp2.0/Suave.Tests.dll failed.)
-> Start of process /suave/src/Suave.Tests/bin/Release/netcoreapp2.0/Suave.Tests.dll failed.
-> Win32Exception: Permission denied

Bugs:

• Assumes the dll is executable
• No way to tell it to use dotnet to run it
• The dotnet-run on mono bug is triggered "aka Mono not supported"
• The parallel-workers options is broken and outputs a zero. Instead of overriding this setting for expecto I'm wondering what's wrong with the default implementation that DOES work cross platform? https://github.com/haf/expecto/blob/master/Expecto/Expecto.fs#L944

[matthid]

/cc @jackfoxy see that's why I didn't do it ;)

[jackfoxy]

@matthid I'm not certain which "it" you are referring to, but I do see you merged rc6 into master, including Fake.DotNet.Testing.Expecto

[matthid]

With "it" I mean this bug report. The problem is that expecto on netcore works differently. This means the module needs some rework :/

[jackfoxy]

Unfortunately I'm not a good candidate for the task, as I only ever work in Windows.

[baronfel]

It's a bit larger than just windows or not. On .net core any sort of executable binary is now compiled as a dll and must be run via the 'dotnet path/to/dll' command, instead of involing manually. So that's where most of the work is, determining which runtime to execute on.

[matthid]

@baronfel I don't feel like it needs to be detected automatically. I think it would be completely fine to switch via parameter or a new function.