Disable color output in pipes

[ai]

Most of color output libraries like chalk, supports-color, or colorette do not enable color output in pipes.

it is useful for cases like:

$ npx app > log.txt
# you send the log via email
$ vscode log.txt
# now you can’t read the log in a text editor because of color marks

Also, color marks could force grep to have unexpected results.

@lukeed What do you think if we will add the same process.stdout.isTTY check to kleur as well?

[lukeed]

Hey, it should be fine, but let me investigate some dependents to make sure it's not depended on.

I'll add some extra process-based tests after this PR

[lukeed]

Ok, the conditions have to be tweaked a little bit, but I'll take care of it. You're right that we should match the default chalk behavior – but still give a way to get colors back on if you want it.

[codecov-commenter]

Codecov Report

Merging #33 into master will decrease coverage by 1.29%.
The diff coverage is 100.00%.

@@             Coverage Diff             @@
##            master      #33      +/-   ##
===========================================
- Coverage   100.00%   98.70%   -1.30%     
===========================================
  Files            2        2              
  Lines          151      155       +4     
  Branches        28       30       +2     
===========================================
+ Hits           151      153       +2     
- Misses           0        2       +2     

Impacted Files	Coverage Δ
colors.mjs	97.95% <100.00%> (-2.05%)	⬇️
index.mjs	99.05% <100.00%> (-0.95%)	⬇️

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[lukeed]

I wanted to keep my pretty formatting inside GitHub Actions 😇

Taking your original example, along with these changes:

$ node app.js > log.txt 
#=> NO COLORS

$ node app.js
#=> COLORS

$ FORCE_COLOR=1 node app.js > log.txt
#=> COLORS

$ FORCE_COLOR=0 node app.js > log.txt
#=> NO COLORS

@ai If you can confirm that it also looks correct to you, then this is ready to go.

[ai]

Do we enable or disable color output on GitHub Action?

GitHub Action user can call tool with a pipe as well.

[lukeed]

Right now it's enabled on GH because I thought supports-color did this by default, but it doesn't actually.
Will revert~

[ai]

LGTM. Thanks for fixing the tests 👍

[lukeed]

Now have bash tests in place for detections with & without TTY sessions.

Sorry for notification noise; wanted it all in together.
Thanks for report/PR 👍