ansi-styles 6.2.3: rgbToAnsi256

Clean-room public code sample — generation instructions

Write a brand-new, minimal, self-contained code sample in this clean-room directory.
Do not copy, paraphrase, or reference any existing project source. Work only from this spec.

A csx.json manifest scaffold already exists. Do not recreate it from memory. Preserve its case.goal, packages and symbols; fill its empty case.contract with exact assertions and correct its environment, commands and verifierAdapter for the files you generate.

Goal: verify ansi-styles.rgbToAnsi256 in pkg:npm/ansi-styles@6.2.3
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/ansi-styles@6.2.3
Demonstrate these symbols/APIs:
  - ansi-styles.rgbToAnsi256

Rules:
  - One focused purpose; the smallest project that proves the goal.
  - Include a contract test (test/contract.*) that runs OFFLINE and exits 0 exactly when the goal behavior works.
  - Pin every dependency with a lockfile so resolution is reproducible.
  - No secrets, credentials, or tokens. No real URLs (only example.com or localhost). No absolute paths.
  - No personal names, emails, company names, or project identifiers of any kind.
  - No binaries and no generated output (node_modules, dist, target, venv, .git, .env).
  - Keep it under 200 files and 256KB packed.

{"case":{"caseId":"case:sha256:c8d31abdf43522afd0ea873a9bd21aa970919019cebabcdd2e571589898855cc","contract":["ansiStyles.rgbToAnsi256 converts RGB values to ANSI 256 color space number","ansiStyles.rgbToAnsi256(255, 255, 255) returns 231","ansiStyles.rgbToAnsi256(0, 0, 0) returns 16","ansiStyles.rgbToAnsi256(255, 0, 0) returns 196"],"goal":"verify ansi-styles.rgbToAnsi256 in pkg:npm/ansi-styles@6.2.3","kind":"HOW","packages":["pkg:npm/ansi-styles@6.2.3"],"schemaVersion":1,"symbols":["ansi-styles.rgbToAnsi256"]},"contractCommand":["node","test/contract.mjs"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"npm","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"npm","schemaVersion":1},"license":"MIT-0","packages":["pkg:npm/ansi-styles@6.2.3"],"schemaVersion":1,"subject":"pkg:npm/ansi-styles@6.2.3","symbols":["ansi-styles.rgbToAnsi256"],"verifierAdapter":"node-typescript@1"}

import ansiStyles from 'ansi-styles';

export function rgbToAnsi256(red, green, blue) {
  return ansiStyles.rgbToAnsi256(red, green, blue);
}

export function formatRgb256Text(red, green, blue, text) {
  const code = ansiStyles.rgbToAnsi256(red, green, blue);
  return `${ansiStyles.color.ansi256(code)}${text}${ansiStyles.color.close}`;
}

{
  "name": "sample-ansi-styles",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-ansi-styles",
      "version": "1.0.0",
      "dependencies": {
        "ansi-styles": "6.2.3"
      }
    },
    "node_modules/ansi-styles": {
      "version": "6.2.3",
      "resolved": "https://registry.npmjs.org/ansi-styles/-/ansi-styles-6.2.3.tgz",
      "integrity": "sha512-4Dj6M28JB+oAH8kFkTLUo+a2jwOFkuqb3yucU0CANcRRUbxS0cP0nZYCGjcc3BNXwRIsUVmDGgzawme7zvJHvg==",
      "license": "MIT",
      "engines": {
        "node": ">=12"
      },
      "funding": {
        "url": "https://github.com/chalk/ansi-styles?sponsor=1"
      }
    }
  }
}

{
  "name": "sample-ansi-styles",
  "version": "1.0.0",
  "type": "module",
  "private": true,
  "dependencies": {
    "ansi-styles": "6.2.3"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify ansi-styles.rgbToAnsi256 in pkg:npm/ansi-styles@6.2.3",
  "kind": "HOW",
  "packages": [
    "pkg:npm/ansi-styles@6.2.3"
  ],
  "symbols": [
    "ansi-styles.rgbToAnsi256"
  ]
}

import assert from 'node:assert/strict';
import ansiStyles from 'ansi-styles';
import { rgbToAnsi256, formatRgb256Text } from '../index.mjs';

// Verify ansiStyles.rgbToAnsi256 directly
assert.equal(typeof ansiStyles.rgbToAnsi256, 'function');
assert.equal(ansiStyles.rgbToAnsi256(255, 255, 255), 231);
assert.equal(ansiStyles.rgbToAnsi256(0, 0, 0), 16);
assert.equal(ansiStyles.rgbToAnsi256(255, 0, 0), 196);
assert.equal(ansiStyles.rgbToAnsi256(0, 255, 0), 46);
assert.equal(ansiStyles.rgbToAnsi256(0, 0, 255), 21);

// Verify module wrapper
assert.equal(rgbToAnsi256(255, 255, 255), 231);
assert.equal(rgbToAnsi256(0, 0, 0), 16);
assert.equal(formatRgb256Text(255, 0, 0, 'hello'), '\x1b[38;5;196mhello\x1b[39m');

console.log('Contract verification passed for ansi-styles.rgbToAnsi256');