termenv VS color

For example: https://github.com/muesli/termenv // Clear the visible portion of the terminal output := termenv.NewOutput(os.Stdout) output.ClearScreen()

Why not let termenv do the hard part of making this portable across terminals? It also supports lesser-known conventions like NO_COLOR.

Termenv

Look, you and I may have sane ANSI 16 colours, but it’ll be a very significant fraction of people that don’t (and almost no one will customise the next 240 colours). Remember things like that there’s a fairly high chance that blue is almost invisible against black, and even bright blue’s contrast is commonly much too low—to say nothing of the limited palette range.

But what this program is doing is using termenv’s HasDarkBackground function to decide whether the terminal is light or dark, and is then specifying RGB colours. I’d guess that it’ll try to guess whether to use 16 colours, 256 colours or 24-bit colour, but I don’t know. But the way it figures out the terminal’s background colour… ugh. Some terminals will support it, but for many it’ll fail and just assume black. Looks like on unix you could set an environment variable COLORFGBG to override this, https://github.com/muesli/termenv/blob/6bb55115565c27f4cc681..., but if you’re on Windows, tough luck, apparently you’re not allowed to have run `color f0` (Command Prompt) or similar: https://github.com/muesli/termenv/blob/537e36cb0472a69a3c828....

The simple fact of the matter is that there are no particularly good solutions for handling colour in terminals if you want the colours to cohere and map to real-world colour understanding, which is what something like this would prefer to be able to do.

So i have a cli tool thats outputting some text to the cli stdout, i would like the output to be colored, so i used a library called color (github.com/fatih/color), basically the problem is when i output to stdout its fine but when i do something like ./tool | tee -a file.txt the colors disappear from terminal and also not in the output file, why is that and how do i prevent that ?

printer.go - Handles printing (showing) information to the user. This is where fatih/color is being used, so we can print pretty information with colors.

Note, you also need to handle piping to other programs or sending output to a file. See the logic in https://github.com/fatih/color/blob/master/color.go, https://github.com/mattn/go-colorable and https://github.com/mattn/go-isatty.

The platform I'm using is Windows, and I found that prior to Win10 there was no support for ANSI escape codes in the command line, but I have Win10 and am pretty sure my version is up-to-date enough to have this support. I have also been successfully using Fatih's color package, so I had assumed that the escape codes were working. But they are not working when I do it manually, so fmt.Print("\033[F") does not work.

same person that wrote this module i use all the time. https://github.com/fatih/color ???

I am using github.com/fatih/color as an example because it is a very simple library to test this problem out with.

I would use bytes.Contains instead of string.Contains and I would use github.com/fatih/color for ansi colours rather than re-implienting it yourself. Best not to call log.Fatal in functions other than main - it makes testing hard. Instead they should return an error after their main return value.

What’s the benefit over a well established library such as https://github.com/fatih/color ?