@babel/types 7.29.7: identifier

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 @babel/types.identifier in pkg:npm/%40babel/types@7.29.7
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/%40babel/types@7.29.7
Demonstrate these symbols/APIs:
  - @babel/types.identifier

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:sha256:27c77e674b0b20b4038c47374cb1b12d36235d188b2c01ec15964c229e552906","contract":["identifier constructs an Identifier AST node with the specified name","identifier correctly creates Identifier nodes for various valid string names including empty strings","identifier throws a TypeError when called with non-string arguments such as null, undefined, or numbers","isIdentifier validates that the constructed node is an Identifier AST node"],"goal":"verify @babel/types.identifier in pkg:npm/%40babel/types@7.29.7","kind":"HOW","packages":["pkg:npm/%40babel/types@7.29.7"],"schemaVersion":1,"symbols":["@babel/types.identifier"]},"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/%40babel/types@7.29.7"],"schemaVersion":1,"subject":"pkg:npm/%40babel/types@7.29.7","symbols":["@babel/types.identifier"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-babel-types-identifier",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-babel-types-identifier",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "@babel/types": "7.29.7"
      }
    },
    "node_modules/@babel/helper-string-parser": {
      "version": "7.29.7",
      "resolved": "https://registry.npmjs.org/@babel/helper-string-parser/-/helper-string-parser-7.29.7.tgz",
      "integrity": "sha512-Pb5ijPrZ89GDH8223L4UP8i6QApWxs04RbPQJTeWDV0/keR2E36MeKnyr6LYmUUvqRRI+Iv87SuF1W6ErINzYw==",
      "license": "MIT",
      "engines": {
        "node": ">=6.9.0"
      }
    },
    "node_modules/@babel/helper-validator-identifier": {
      "version": "7.29.7",
      "resolved": "https://registry.npmjs.org/@babel/helper-validator-identifier/-/helper-validator-identifier-7.29.7.tgz",
      "integrity": "sha512-qehxGkRj55h/ff8EMaJ+cYhyaKlHIxqYDn682wQD7RNp9UujOQsHog2uS0r2vzr4pW+sXf90NeeayjcNaX3fFg==",
      "license": "MIT",
      "engines": {
        "node": ">=6.9.0"
      }
    },
    "node_modules/@babel/types": {
      "version": "7.29.7",
      "resolved": "https://registry.npmjs.org/@babel/types/-/types-7.29.7.tgz",
      "integrity": "sha512-4zBIxpPzowiZpusoFkyGVwakdRJUyuH5PxQ/PrqghfdFWWasvnCdPfQXHrenDai+gyLARulZjZowCOj6fjT4pA==",
      "license": "MIT",
      "dependencies": {
        "@babel/helper-string-parser": "^7.29.7",
        "@babel/helper-validator-identifier": "^7.29.7"
      },
      "engines": {
        "node": ">=6.9.0"
      }
    }
  }
}

{
  "name": "sample-babel-types-identifier",
  "version": "1.0.0",
  "private": true,
  "type": "module",
  "license": "MIT-0",
  "dependencies": {
    "@babel/types": "7.29.7"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify @babel/types.identifier in pkg:npm/%40babel/types@7.29.7",
  "kind": "HOW",
  "packages": [
    "pkg:npm/%40babel/types@7.29.7"
  ],
  "symbols": [
    "@babel/types.identifier"
  ]
}

import * as t from "@babel/types";

export function createIdentifier(name) {
  return t.identifier(name);
}

export function createVariableDeclarator(name, init = null) {
  const id = t.identifier(name);
  return t.variableDeclarator(id, init);
}

export function extractIdentifierName(node) {
  if (t.isIdentifier(node)) {
    return node.name;
  }
  return null;
}

import assert from "node:assert/strict";
import * as t from "@babel/types";
import {
  createIdentifier,
  createVariableDeclarator,
  extractIdentifierName
} from "../src/index.mjs";

// Test 1: identifier constructs an Identifier AST node with the specified name
{
  const node = createIdentifier("myVariable");
  assert.equal(node.type, "Identifier");
  assert.equal(node.name, "myVariable");
  assert.equal(t.isIdentifier(node), true);
}

// Test 2: identifier correctly creates Identifier nodes for various valid string names including empty strings
{
  const emptyId = createIdentifier("");
  assert.equal(emptyId.type, "Identifier");
  assert.equal(emptyId.name, "");

  const dollarId = createIdentifier("$value");
  assert.equal(dollarId.type, "Identifier");
  assert.equal(dollarId.name, "$value");

  const unicodeId = createIdentifier("变量");
  assert.equal(unicodeId.type, "Identifier");
  assert.equal(unicodeId.name, "变量");

  const declarator = createVariableDeclarator("count", t.numericLiteral(0));
  assert.equal(declarator.type, "VariableDeclarator");
  assert.equal(declarator.id.type, "Identifier");
  assert.equal(declarator.id.name, "count");
  assert.equal(declarator.init.value, 0);
}

// Test 3: identifier throws a TypeError when called with non-string arguments such as null, undefined, or numbers
{
  assert.throws(
    () => {
      createIdentifier(null);
    },
    {
      name: "TypeError",
      message: /Property name expected type of string but got null/
    }
  );

  assert.throws(
    () => {
      createIdentifier(undefined);
    },
    {
      name: "TypeError",
      message: /Property name expected type of string but got undefined/
    }
  );

  assert.throws(
    () => {
      createIdentifier(123);
    },
    {
      name: "TypeError",
      message: /Property name expected type of string but got number/
    }
  );
}

// Test 4: isIdentifier validates that the constructed node is an Identifier AST node
{
  const id = t.identifier("x");
  assert.equal(extractIdentifierName(id), "x");
  assert.equal(t.isIdentifier(id), true);
  assert.equal(t.isIdentifier(id, { name: "x" }), true);
  assert.equal(t.isIdentifier(id, { name: "y" }), false);
  assert.equal(extractIdentifierName({ type: "Literal" }), null);
  assert.equal(extractIdentifierName(null), null);
}

console.log("All @babel/types.identifier contract tests passed successfully.");