check-error 2.1.3: compatibleInstance

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 check-error.compatibleInstance in pkg:npm/check-error@2.1.3
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/check-error@2.1.3
Demonstrate these symbols/APIs:
  - check-error.compatibleInstance

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:d5a35f357ece9f73e89600901b86a5ecdd93d217e9b3fee2118e962d780b73de","contract":["compatibleInstance returns true when thrown and errorLike are the same Error instance","compatibleInstance returns false when thrown and errorLike are different Error instances","compatibleInstance returns true when thrown and errorLike are the same custom Error subclass instance","compatibleInstance returns false when errorLike is an Error constructor instead of an instance","compatibleInstance returns false when errorLike is a non-Error value including null, undefined, object, and string"],"goal":"verify check-error.compatibleInstance in pkg:npm/check-error@2.1.3","kind":"HOW","packages":["pkg:npm/check-error@2.1.3"],"schemaVersion":1,"symbols":["check-error.compatibleInstance"]},"contractCommand":["node","test/contract.mjs"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"npm","executionContext":"node","language":"javascript","libc":"glibc","libcVersion":"2.39","moduleSystem":"esm","os":"linux","osVersionBucket":"24","packageManager":"npm","packageManagerVersion":"10.9.8","runtime":"node","runtimeVersion":"22.23.2","schemaVersion":1},"license":"MIT-0","packages":["pkg:npm/check-error@2.1.3"],"schemaVersion":1,"subject":"pkg:npm/check-error@2.1.3","symbols":["check-error.compatibleInstance"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-check-error",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-check-error",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "check-error": "2.1.3"
      }
    },
    "node_modules/check-error": {
      "version": "2.1.3",
      "resolved": "https://registry.npmjs.org/check-error/-/check-error-2.1.3.tgz",
      "integrity": "sha512-PAJdDJusoxnwm1VwW07VWwUN1sl7smmC3OKggvndJFadxxDRyFJBX/ggnu/KE4kQAB7a3Dp8f/YXC1FlUprWmA==",
      "license": "MIT",
      "engines": {
        "node": ">= 16"
      }
    }
  }
}

{
  "name": "sample-check-error",
  "version": "1.0.0",
  "type": "module",
  "license": "MIT-0",
  "dependencies": {
    "check-error": "2.1.3"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify check-error.compatibleInstance in pkg:npm/check-error@2.1.3",
  "kind": "HOW",
  "packages": [
    "pkg:npm/check-error@2.1.3"
  ],
  "symbols": [
    "check-error.compatibleInstance"
  ]
}

import assert from 'node:assert/strict';
import { compatibleInstance } from 'check-error';

// 1. compatibleInstance returns true when thrown and errorLike are the same Error instance
const standardErr = new Error('something failed');
assert.equal(compatibleInstance(standardErr, standardErr), true);

const typeErr = new TypeError('invalid type');
assert.equal(compatibleInstance(typeErr, typeErr), true);

const rangeErr = new RangeError('out of range');
assert.equal(compatibleInstance(rangeErr, rangeErr), true);

// 2. compatibleInstance returns false when thrown and errorLike are different Error instances
const anotherStandardErr = new Error('something failed');
assert.equal(compatibleInstance(standardErr, anotherStandardErr), false);
assert.equal(compatibleInstance(typeErr, new TypeError('invalid type')), false);
assert.equal(compatibleInstance(standardErr, typeErr), false);

// 3. compatibleInstance returns true when thrown and errorLike are the same custom Error subclass instance
class CustomError extends Error {}
const customErr = new CustomError('custom message');
assert.equal(compatibleInstance(customErr, customErr), true);

const anotherCustomErr = new CustomError('custom message');
assert.equal(compatibleInstance(customErr, anotherCustomErr), false);

// 4. compatibleInstance returns false when errorLike is an Error constructor instead of an instance
assert.equal(compatibleInstance(standardErr, Error), false);
assert.equal(compatibleInstance(typeErr, TypeError), false);
assert.equal(compatibleInstance(customErr, CustomError), false);

// 5. compatibleInstance returns false when errorLike is a non-Error value including null, undefined, object, and string
assert.equal(compatibleInstance(standardErr, null), false);
assert.equal(compatibleInstance(standardErr, undefined), false);
assert.equal(compatibleInstance(standardErr, 'something failed'), false);
assert.equal(compatibleInstance(standardErr, 123), false);
assert.equal(compatibleInstance(standardErr, {}), false);
assert.equal(compatibleInstance(standardErr, { message: 'something failed' }), false);

console.log('All check-error.compatibleInstance contract assertions passed.');