fast-levenshtein 2.0.6

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 pkg:npm/fast-levenshtein@2.0.6
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/fast-levenshtein@2.0.6
Constraints:
  - executionContext: node
Required runtime conditions:
  - ecosystem: npm
  - language: javascript
  - moduleSystem: cjs
  - packageManager: npm@10.9.8
  - runtime: node@22.23.2

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:sha256:09cb06356d013e330dea6d1199947acd5dc73882faec29fc95c3ddc2b52bb872","constraints":{"executionContext":"node"},"contract":["assert get returns 0 for identical strings","assert get returns string length when comparing against empty string","assert get computes correct Levenshtein distance for single-character edits","assert get computes correct Levenshtein distance for multi-character edits","assert get supports useCollator option for locale-sensitive comparison"],"goal":"verify pkg:npm/fast-levenshtein@2.0.6","kind":"HOW","packages":["pkg:npm/fast-levenshtein@2.0.6"],"schemaVersion":1},"contractCommand":["node","test/contract.mjs"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"npm","executionContext":"node","language":"javascript","libc":"glibc","libcVersion":"2.39","moduleSystem":"cjs","os":"linux","osVersionBucket":"24","packageManager":"npm","packageManagerVersion":"10.9.8","runtime":"node","runtimeVersion":"22.23.2","schemaVersion":1},"license":"MIT-0","packages":["pkg:npm/fast-levenshtein@2.0.6"],"schemaVersion":1,"subject":"pkg:npm/fast-levenshtein@2.0.6","verifierAdapter":"node-typescript@1"}

{
  "name": "sample-fast-levenshtein",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-fast-levenshtein",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "fast-levenshtein": "2.0.6"
      }
    },
    "node_modules/fast-levenshtein": {
      "version": "2.0.6",
      "resolved": "https://registry.npmjs.org/fast-levenshtein/-/fast-levenshtein-2.0.6.tgz",
      "integrity": "sha512-DCXu6Ifhqcks7TZKY3Hxp3y6qphY5SJZmrWMDrKcERSOXWQdMhU9Ig/PYrzyw/ul9jOIyh0N4M0tbC5hodg8dw==",
      "license": "MIT"
    }
  }
}

{
  "name": "sample-fast-levenshtein",
  "version": "1.0.0",
  "type": "module",
  "license": "MIT-0",
  "dependencies": {
    "fast-levenshtein": "2.0.6"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify pkg:npm/fast-levenshtein@2.0.6",
  "kind": "HOW",
  "packages": [
    "pkg:npm/fast-levenshtein@2.0.6"
  ],
  "constraints": {
    "executionContext": "node"
  },
  "runtimeConditions": {
    "ecosystem": "npm",
    "language": "javascript",
    "moduleSystem": "cjs",
    "packageManager": "npm@10.9.8",
    "runtime": "node@22.23.2"
  }
}

import assert from 'node:assert/strict';
import { createRequire } from 'node:module';

const require = createRequire(import.meta.url);
const levenshtein = require('fast-levenshtein');

// 1. Calculate Levenshtein distance between identical strings returns 0
assert.equal(levenshtein.get('hello', 'hello'), 0);
assert.equal(levenshtein.get('', ''), 0);

// 2. Calculate distance between string and empty string returns string length
assert.equal(levenshtein.get('kitten', ''), 6);
assert.equal(levenshtein.get('', 'sitting'), 7);

// 3. Calculate distance for single-character edits (insertions, deletions, substitutions)
assert.equal(levenshtein.get('cat', 'cats'), 1);
assert.equal(levenshtein.get('cats', 'cat'), 1);
assert.equal(levenshtein.get('cat', 'bat'), 1);

// 4. Calculate distance for multi-character edits
assert.equal(levenshtein.get('kitten', 'sitting'), 3);
assert.equal(levenshtein.get('saturday', 'sunday'), 3);
assert.equal(levenshtein.get('book', 'back'), 2);

// 5. Support useCollator option for locale-sensitive comparison
assert.equal(levenshtein.get('a', 'b', { useCollator: true }), 1);
assert.equal(levenshtein.get('hello', 'hello', { useCollator: true }), 0);