strip-final-newline 2.0.0: stripFinalNewline

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 stripFinalNewline in pkg:npm/strip-final-newline@2.0.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/strip-final-newline@2.0.0
Demonstrate these symbols/APIs:
  - stripFinalNewline

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:sha256:942539342ecdca1874f9513751eadfd46e9421637383e2d196552586fc49fa0d","contract":["stripFinalNewline('foo\\n') === 'foo'","stripFinalNewline('foo\\r\\n') === 'foo'","stripFinalNewline('foo\\n\\n') === 'foo\\n'","stripFinalNewline('foo') === 'foo'","stripFinalNewline(Buffer.from('foo\\n')) equals Buffer.from('foo')","stripFinalNewline(Buffer.from('foo\\r\\n')) equals Buffer.from('foo')","stripFinalNewline(Buffer.from('foo')) equals Buffer.from('foo')"],"goal":"verify stripFinalNewline in pkg:npm/strip-final-newline@2.0.0","kind":"HOW","packages":["pkg:npm/strip-final-newline@2.0.0"],"schemaVersion":1,"symbols":["stripFinalNewline"]},"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/strip-final-newline@2.0.0"],"schemaVersion":1,"subject":"pkg:npm/strip-final-newline@2.0.0","symbols":["stripFinalNewline"],"verifierAdapter":"node-typescript@1"}

import stripFinalNewline from 'strip-final-newline';

export function removeTrailingNewline(input) {
  return stripFinalNewline(input);
}

{
  "name": "sample-strip-final-newline",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-strip-final-newline",
      "version": "1.0.0",
      "dependencies": {
        "strip-final-newline": "2.0.0"
      }
    },
    "node_modules/strip-final-newline": {
      "version": "2.0.0",
      "resolved": "https://registry.npmjs.org/strip-final-newline/-/strip-final-newline-2.0.0.tgz",
      "integrity": "sha512-BrpvfNAE3dcvq7ll3xVumzjKjZQ5tI1sEUIKr3Uoks0XUl45St3FlatVqef9prk4jRDzhW6WZg+3bk93y6pLjA==",
      "license": "MIT",
      "engines": {
        "node": ">=6"
      }
    }
  }
}

{
  "name": "sample-strip-final-newline",
  "version": "1.0.0",
  "type": "module",
  "private": true,
  "dependencies": {
    "strip-final-newline": "2.0.0"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify stripFinalNewline in pkg:npm/strip-final-newline@2.0.0",
  "kind": "HOW",
  "packages": [
    "pkg:npm/strip-final-newline@2.0.0"
  ],
  "symbols": [
    "stripFinalNewline"
  ]
}

import assert from 'node:assert';
import stripFinalNewline from 'strip-final-newline';

// Strips single trailing LF newline from string
assert.strictEqual(stripFinalNewline('foo\n'), 'foo');

// Strips single trailing CRLF newline from string
assert.strictEqual(stripFinalNewline('foo\r\n'), 'foo');

// Only strips the final newline when multiple trailing newlines exist
assert.strictEqual(stripFinalNewline('foo\n\n'), 'foo\n');

// Leaves string without trailing newline unchanged
assert.strictEqual(stripFinalNewline('foo'), 'foo');

// Strips single trailing LF newline from Buffer
assert.deepStrictEqual(stripFinalNewline(Buffer.from('foo\n')), Buffer.from('foo'));

// Strips single trailing CRLF newline from Buffer
assert.deepStrictEqual(stripFinalNewline(Buffer.from('foo\r\n')), Buffer.from('foo'));

// Leaves Buffer without trailing newline unchanged
assert.deepStrictEqual(stripFinalNewline(Buffer.from('foo')), Buffer.from('foo'));