use memory_buffer to make color print behave atomic #1348

[tankiJong]

I agree that my contributions are licensed under the {fmt} license, and agree to future changes to the licensing.

I did not have time to read the whole coding standard, but I did try to following the existing style.
Please do point out if there is any formating issue.

Thanks for your time :)

[tankiJong]

I do not feel format_to( buf, "{}", format ); is the right way to put it..?

I try to format it and vprint the whole complete string but the complier complains when I type vprintf(f, buf.data());. Please inspire me the proper way to do it.

Thanks!

[vitaut]

Thanks for the PR.

[tankiJong]

Thanks for the feedback.
I will ping you again when I feel it's in shape and rebase the change into a single commit when you think it looks good:)

[tankiJong]

@vitaut I am happy with the current version and seems CI is also happy now:D So feel free to review it.

[vitaut]

Merged, thanks!

[orivej]

Although it is unusual, the result of formatting args may contain zero bytes, then this fputs will truncate it and will not reset the color.

[tankiJong]

Hi, thanks for bring that up! But I don't think I understand what you mean... Could you give an example?

[orivej]

See the test in https://github.com/fmtlib/fmt/pull/1356/files

[tankiJong]

Ah.. Yes, that's a good point, in case there is a terminator in the string, that won't work.