std.io.tty: add detectTtyConfigForce for forcing color

[dweiller]

This PR adds fn std.io.tty.detectConfigForce(File, bool) Config which accepts an extra parameter to force coloring if the platform supports it. There are two code paths where .no_color will be returned: if the platform is wasi, or on windows if the windows.kernel32.GetConsoleScreenBufferInfo() test fails - other options in this case could be to return an error, or .escape_codes (though this might be unexpected). If you want to force escape codes on wasi for some reason, you don't need to do TTY detection, just use .escape_codes directly.

[dweiller]

I'm not sure I understand the CI failure - it looks like it's something to do with docgen. The error says it's a problem with wasi not supporting hasEnvVarConstants, but that doesn't make sense to me as the changes should not have changed the behaviour of std.io.tty.detectConfig() at all.

[dweiller]

Or is it something specifically to do with bootstrapping? It looks like build-debug/zig2 is the executable that's being used during the failure.

[andrewrk]

I pushed a commit with my opinion of how it should be. What do you think?

[andrewrk]

This seems like a nicer way to go. I'm unsure what the ZIG_DEBUG_COLOR environment variable was for - is there somewhere else in the codebase that was using it?

It was moved from std.debug in #15806.

[dweiller]

Looks like ZIG_DEBUG_COLOR is referenced in 3 others files:

~/S/z/src (master) > rg ZIG_DEBUG_COLOR
lib/build_runner.zig
285:        .escape_codes => try builder.env_map.put("ZIG_DEBUG_COLOR", "1"),

lib/std/io/tty.zig
16:    } else if (process.hasEnvVarConstant("ZIG_DEBUG_COLOR")) {


test/src/StackTrace.zig
84:    run.removeEnvironmentVariable("ZIG_DEBUG_COLOR");

doc/docgen.zig
1308:    try env_map.put("ZIG_DEBUG_COLOR", "1");

[andrewrk]

ZIG_DEBUG_COLOR was renamed to YES_COLOR

[dweiller]

whoops

[dweiller]

I'll be happy with that. You won't be able to force the windows specific way of colouring, but I don't know if that's something you actually ever want to do.