refactor!: replace ansi-colors with smaller and faster ansis

[webdiscus]

PR Checklist

• Addresses an existing open issue: fixes #000
• That issue was marked as status: accepting prs
• Steps in CONTRIBUTING.md were taken

Overview

This PR replaces the outdated ansi-colors (last update 3 years ago) package with smaller and faster ansis.

Benefits of ansis

• Supports both ESM and CommonJS
• Supports Bun and Deno runtimes
• Supports TypeScript
• Ansis is compatible with ansi-colors API, plus supports named import: import { red, yellow } from 'ansis'
• Installed package size only 10 kB (ansi-colors 26 kB), see Compare the size of most popular packages
• 7-10x faster than ansi-colors, see Benchmarks
• Using named import your code will be clean and more readable:

  - console.error(ansi.red(`Error: ${result.error.message}`));
  + console.error(red`Error: ${result.error.message}`); // <= shorter and more readable

• Supports ANSI 256 colors and TrueColor with Fallback: TrueColor → 256 colors → 16 colors → no colors
• Supports environment variables NO_COLOR FORCE_COLOR and flags --no-color --color
• Both Ansis and Picocolors (does't support named import) are recommended by the ES Tooling community as smallest and fastest packages.

Packages that already use ansis

• nestjs/nest,
• sequelize/core
• facebook/stylex
• salesforcecli/cli
• grafana/faro-javascript-bundler-plugins
• and thousands others

Test

This PR does not require unit/integration tests.

But you can do the manual test.

Install the fork

git clone https://github.com/webdiscus/mocha.git
cd mocha
git checkout switch-to-ansis
npm i
npm run build

Test changed files

Cmd:

node ./bin/mocha.js -h

In console output will be displayed color text:

Cmd:

node ./bin/mocha.js -h --no-color

In console output will be displayed b&w text:

Cmd:

node ./bin/mocha.js -R

In console output will be displayed red text:

[JoshuaKGoldberg]

Hey thanks for sending this in @webdiscus!

• Addresses an existing open issue: fixes #000
• That issue was marked as status: accepting prs

In the future, could you please file issues before sending nontrivial PRs? Per our contributing guidelines we prefer discussing changes before implementing. It can be hard to know whether an approach is the right one to spend development time on, and it's awkward telling someone to redo lots of work.

This PR is a good example of that: it's not clear to me why you'd want ansis (300k weekly downloads) over picocolors (31m weekly downloads).

I'll note that per https://github.com/webdiscus/ansis?tab=readme-ov-file#-unpacked-size, picocolors is both a smaller size and faster when applying single styles. But both of those are such negligibly small differences that I doubt they matter for Mocha's usage.