react-is 18.3.1: isContextConsumer

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 react-is.isContextConsumer in pkg:npm/react-is@18.3.1
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/react-is@18.3.1
Demonstrate these symbols/APIs:
  - react-is.isContextConsumer
Required runtime conditions:
  - ecosystem: golang
  - language: go
  - packageManager: go@1.26.6
  - runtime: go@1.26.6

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:sha256:1259a7ac086834770504af52921dafdb7de8a175317c2e778810e884323fab00","contract":["isContextConsumer correctly identifies React Context Consumer element objects","isContextConsumer rejects plain DOM elements, provider elements, non-element objects, and primitives"],"goal":"verify react-is.isContextConsumer in pkg:npm/react-is@18.3.1","kind":"HOW","packages":["pkg:npm/react-is@18.3.1"],"schemaVersion":1,"symbols":["react-is.isContextConsumer"]},"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/react-is@18.3.1"],"schemaVersion":1,"subject":"pkg:npm/react-is@18.3.1","symbols":["react-is.isContextConsumer"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-react-is-context-consumer",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-react-is-context-consumer",
      "version": "1.0.0",
      "dependencies": {
        "react-is": "18.3.1"
      }
    },
    "node_modules/react-is": {
      "version": "18.3.1",
      "resolved": "https://registry.npmjs.org/react-is/-/react-is-18.3.1.tgz",
      "integrity": "sha512-/LLMVyas0ljjAtoYiPqYiL8VWXzUUdThrmU5+n20DZv+a+ClRoevUzw5JxU+Ieh5/c87ytoTBV9G1FiKfNJdmg==",
      "license": "MIT"
    }
  }
}

{
  "name": "sample-react-is-context-consumer",
  "version": "1.0.0",
  "private": true,
  "description": "Clean-room verification of react-is isContextConsumer API",
  "type": "module",
  "main": "src/index.js",
  "dependencies": {
    "react-is": "18.3.1"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify react-is.isContextConsumer in pkg:npm/react-is@18.3.1",
  "kind": "HOW",
  "packages": [
    "pkg:npm/react-is@18.3.1"
  ],
  "symbols": [
    "react-is.isContextConsumer"
  ],
  "runtimeConditions": {
    "ecosystem": "golang",
    "language": "go",
    "packageManager": "go@1.26.6",
    "runtime": "go@1.26.6"
  }
}

import { isContextConsumer } from 'react-is';

/**
 * Checks whether a given value is a React Context Consumer element.
 *
 * @param {*} value - The value or React element to test.
 * @returns {boolean} True if the value is a Context Consumer element, false otherwise.
 */
export function checkIsContextConsumer(value) {
  return isContextConsumer(value);
}

export { isContextConsumer };

import assert from 'node:assert/strict';
import { checkIsContextConsumer, isContextConsumer } from '../src/index.js';

// 1. Export verification
assert.equal(typeof isContextConsumer, 'function', 'isContextConsumer must be exported as a function');
assert.equal(typeof checkIsContextConsumer, 'function', 'checkIsContextConsumer must be exported as a function');

// 2. React Context Consumer element detection
const contextConsumerElement = {
  $$typeof: Symbol.for('react.element'),
  type: {
    $$typeof: Symbol.for('react.context'),
  },
  props: {},
  key: null,
  ref: null,
};

assert.equal(
  isContextConsumer(contextConsumerElement),
  true,
  'isContextConsumer must return true for a React Context Consumer element'
);
assert.equal(
  checkIsContextConsumer(contextConsumerElement),
  true,
  'checkIsContextConsumer helper must return true for a React Context Consumer element'
);

// 3. Rejection of other React elements
const plainElement = {
  $$typeof: Symbol.for('react.element'),
  type: 'div',
  props: {},
  key: null,
  ref: null,
};
assert.equal(isContextConsumer(plainElement), false, 'isContextConsumer must return false for a plain DOM element');
assert.equal(checkIsContextConsumer(plainElement), false, 'checkIsContextConsumer must return false for a plain DOM element');

const contextProviderElement = {
  $$typeof: Symbol.for('react.element'),
  type: {
    $$typeof: Symbol.for('react.provider'),
    _context: {},
  },
  props: {},
  key: null,
  ref: null,
};
assert.equal(isContextConsumer(contextProviderElement), false, 'isContextConsumer must return false for a Context Provider element');

const fragmentElement = {
  $$typeof: Symbol.for('react.element'),
  type: Symbol.for('react.fragment'),
  props: {},
  key: null,
  ref: null,
};
assert.equal(isContextConsumer(fragmentElement), false, 'isContextConsumer must return false for a Fragment element');

// 4. Rejection of non-elements and primitives
assert.equal(isContextConsumer(null), false, 'isContextConsumer must return false for null');
assert.equal(isContextConsumer(undefined), false, 'isContextConsumer must return false for undefined');
assert.equal(isContextConsumer({}), false, 'isContextConsumer must return false for empty object');
assert.equal(isContextConsumer(123), false, 'isContextConsumer must return false for numbers');
assert.equal(isContextConsumer('context'), false, 'isContextConsumer must return false for strings');
assert.equal(isContextConsumer(Symbol.for('react.context')), false, 'isContextConsumer must return false for raw context symbol');

console.log('All contract assertions for react-is.isContextConsumer passed.');