Fake coloured text output leaves console colours changed on exit in some circumstances

[SteveGilham]

Description

In a Windows PowerShell console with screen text set to White, running a fake script through dotnet fake can exit with a display colour sticking like

Here the yellow from the warnings has persisted, but depending on the script and the state of the system being built, red, green or light grey can stick instead

Repro steps

Please provide the steps required to reproduce the problem

1. In a Windows PowerShell console, with default colurs (white on dark blue) navigate to a local FAKE repo

2. execute dotnet fake run .\build.fsx --target DotNetCoreUnitTests a number of times

Expected behavior

System colours are preserved always.

Actual behavior

See picture above for an example.

Known workarounds

Save Console.ForegroundColor ,and, to be paranoid, Console.BackgroundColor, on entry to the script, and then execute a final target to set the colours to the saved values.

Related information

• Operating system -- WinX home
• Branch -- released versions, also current release/next
• .NET Runtime, CoreCLR or Mono Version -- .net 4.7 and various .net core
• Indications of severity -- cosmetic
• Version of FAKE (4.X, 5.X) 5.x pre-release certainly, can't remember if seen in 4.x

[BlythMeister]

The issue here is the way fake sets and resets console colour in the listener.

It should use

Console.ResetColor()

Rather than saving the colour and then resetting it manually

[matthid]

@BlythMeister While ResetColor might fix this it would be interesting to know why the current code wouldn't work. AFAIK we serialize everything to a single mailbox processor which should take care of everything?

[matthid]

Or hm, maybe we have indeed two places where we write, one in the fake-runtime and one in Fake.Core.Trace

[matthid]

Related: #1858 haf/expecto#249
Please re-open (or open a new issue) if you encounter this with a runner > 5.14 (which will be released soon)