sqids 0.3.0: default

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 sqids.default in pkg:npm/sqids@0.3.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/sqids@0.3.0
Demonstrate these symbols/APIs:
  - sqids.default

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:sha256:17d2dcf4d952d9ac7210ec7a17d0a86807ecfc04308f3d40fbc252dc63889540","contract":["sqids.default exposes the default export constructor function from sqids module","sqids.default instantiates with default options and creates functional instance","sqids.default encodes an array of integers into an ID string and decodes back","sqids.default instantiates with custom alphabet, minLength, and blocklist options","sqids.default encodes empty array to empty string and decodes empty string to empty array","sqids.default enforces minimum length by padding the generated ID","sqids.default throws when encoding negative numbers or numbers exceeding MAX_SAFE_INTEGER","sqids.default rejects invalid alphabet with multibyte, short length, or duplicates"],"goal":"verify sqids.default in pkg:npm/sqids@0.3.0","kind":"HOW","packages":["pkg:npm/sqids@0.3.0"],"schemaVersion":1,"symbols":["sqids.default"]},"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/sqids@0.3.0"],"schemaVersion":1,"subject":"pkg:npm/sqids@0.3.0","symbols":["sqids.default"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-sqids",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-sqids",
      "version": "1.0.0",
      "dependencies": {
        "sqids": "0.3.0"
      }
    },
    "node_modules/sqids": {
      "version": "0.3.0",
      "resolved": "https://registry.npmjs.org/sqids/-/sqids-0.3.0.tgz",
      "integrity": "sha512-lOQK1ucVg+W6n3FhRwwSeUijxe93b51Bfz5PMRMihVf1iVkl82ePQG7V5vwrhzB11v0NtsR25PSZRGiSomJaJw==",
      "license": "MIT"
    }
  }
}

{
  "name": "sample-sqids",
  "version": "1.0.0",
  "type": "module",
  "private": true,
  "dependencies": {
    "sqids": "0.3.0"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify sqids.default in pkg:npm/sqids@0.3.0",
  "kind": "HOW",
  "packages": [
    "pkg:npm/sqids@0.3.0"
  ],
  "symbols": [
    "sqids.default"
  ]
}

import assert from 'node:assert/strict';
import * as sqids from 'sqids';
import defaultImport from 'sqids';

// 1. sqids.default exposes the default export constructor function from sqids module
{
  assert.ok(typeof sqids.default === 'function', 'sqids.default should be a function/constructor');
  assert.strictEqual(sqids.default, defaultImport, 'sqids.default should match default import');
  const dynamic = await import('sqids');
  assert.strictEqual(dynamic.default, sqids.default, 'dynamic import default should match sqids.default');
}

// 2. sqids.default instantiates with default options and creates functional instance
{
  const instance = new sqids.default();
  assert.ok(instance instanceof sqids.default, 'instance should be an instance of sqids.default');
  assert.strictEqual(typeof instance.encode, 'function', 'instance should have encode method');
  assert.strictEqual(typeof instance.decode, 'function', 'instance should have decode method');
}

// 3. sqids.default encodes an array of integers into an ID string and decodes back
{
  const instance = new sqids.default();
  const numbers = [1, 2, 3];
  const id = instance.encode(numbers);
  assert.strictEqual(typeof id, 'string', 'encode should return a string');
  assert.ok(id.length > 0, 'encoded ID string should not be empty');

  const decoded = instance.decode(id);
  assert.deepStrictEqual(decoded, numbers, 'decode should reproduce original numbers');

  const zeroTest = [0, 42, 9999];
  assert.deepStrictEqual(instance.decode(instance.encode(zeroTest)), zeroTest, 'roundtrip with zero and large numbers');
}

// 4. sqids.default instantiates with custom alphabet, minLength, and blocklist options
{
  const customAlphabet = 'abcdefghijklmnopqrstuvwxyz0123456789';
  const customInstance = new sqids.default({
    alphabet: customAlphabet,
    minLength: 8,
    blocklist: new Set(['blockedword']),
  });
  assert.ok(customInstance instanceof sqids.default, 'custom instance should be an instance of sqids.default');
  const id = customInstance.encode([10, 20]);
  assert.ok(id.length >= 8, 'custom minLength should be honored');
  assert.deepStrictEqual(customInstance.decode(id), [10, 20], 'custom instance should decode correctly');
}

// 5. sqids.default encodes empty array to empty string and decodes empty string to empty array
{
  const instance = new sqids.default();
  assert.strictEqual(instance.encode([]), '', 'encode empty array should return empty string');
  assert.deepStrictEqual(instance.decode(''), [], 'decode empty string should return empty array');
}

// 6. sqids.default enforces minimum length by padding the generated ID
{
  const minLength = 10;
  const instance = new sqids.default({ minLength });
  const id = instance.encode([1]);
  assert.ok(id.length >= minLength, `encoded ID length (${id.length}) should be at least minLength (${minLength})`);
  assert.deepStrictEqual(instance.decode(id), [1], 'padded ID should decode correctly');
}

// 7. sqids.default throws when encoding negative numbers or numbers exceeding MAX_SAFE_INTEGER
{
  const instance = new sqids.default();
  assert.throws(
    () => instance.encode([-1]),
    /Encoding supports numbers between 0 and/,
    'encoding negative number should throw RangeError'
  );
  assert.throws(
    () => instance.encode([Number.MAX_SAFE_INTEGER + 1]),
    /Encoding supports numbers between 0 and/,
    'encoding number > MAX_SAFE_INTEGER should throw RangeError'
  );
}

// 8. sqids.default rejects invalid alphabet with multibyte, short length, or duplicates
{
  assert.throws(
    () => new sqids.default({ alphabet: 'ab' }),
    /Alphabet length must be at least 3/,
    'alphabet length < 3 should throw'
  );
  assert.throws(
    () => new sqids.default({ alphabet: 'aabcdef' }),
    /Alphabet must contain unique characters/,
    'duplicate characters in alphabet should throw'
  );
  assert.throws(
    () => new sqids.default({ alphabet: 'abc\u{1F680}def' }),
    /Alphabet cannot contain multibyte characters/,
    'multibyte characters in alphabet should throw'
  );
}

console.log('All sqids.default contract assertions passed.');