es-module-lexer 1.7.0: parse

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 parse in pkg:npm/es-module-lexer@1.7.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/es-module-lexer@1.7.0
Demonstrate these symbols/APIs:
  - parse

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:f19b2acbf7e0e8f3b8ebb548453df6e6525c547a65827a2ca039694e0eeb7291","contract":["parse is exported as a function from es-module-lexer","parse extracts static imports and named exports with specifier names and position ranges","parse detects dynamic import calls and import.meta expressions","parse identifies facade re-export modules and distinguishes ESM from plain scripts"],"goal":"verify parse in pkg:npm/es-module-lexer@1.7.0","kind":"HOW","packages":["pkg:npm/es-module-lexer@1.7.0"],"schemaVersion":1,"symbols":["parse"]},"contractCommand":["node","test/contract.mjs"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"npm","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/es-module-lexer@1.7.0"],"schemaVersion":1,"subject":"pkg:npm/es-module-lexer@1.7.0","symbols":["parse"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-es-module-lexer-parse",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-es-module-lexer-parse",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "es-module-lexer": "1.7.0"
      }
    },
    "node_modules/es-module-lexer": {
      "version": "1.7.0",
      "resolved": "https://registry.npmjs.org/es-module-lexer/-/es-module-lexer-1.7.0.tgz",
      "integrity": "sha512-jEQoCwk8hyb2AZziIOLhDqpm5+2ww5uIE6lkO/6jcOCusfk6LhMHpXXfBLXTZ7Ydyt0j4VoUQv6uGNYbdW+kBA==",
      "license": "MIT"
    }
  }
}

{
  "name": "sample-es-module-lexer-parse",
  "version": "1.0.0",
  "private": true,
  "description": "verify parse in pkg:npm/es-module-lexer@1.7.0",
  "main": "src/index.js",
  "license": "MIT-0",
  "dependencies": {
    "es-module-lexer": "1.7.0"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify parse in pkg:npm/es-module-lexer@1.7.0",
  "kind": "HOW",
  "packages": [
    "pkg:npm/es-module-lexer@1.7.0"
  ],
  "symbols": [
    "parse"
  ]
}

const { init, parse } = require('es-module-lexer');

/**
 * Parses ES module source code to extract imports, exports, and syntax flags.
 * Ensures the WebAssembly lexer is initialized before parsing.
 * @param {string} source - JavaScript / ES module source code.
 * @param {string} [name] - Optional file name/identifier for error reporting.
 * @returns {Promise<[readonly any[], readonly any[], boolean, boolean]>} Parse result [imports, exports, facade, hasModuleSyntax].
 */
async function parseModule(source, name) {
  await init;
  return parse(source, name);
}

module.exports = {
  parse,
  parseModule
};

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

const require = createRequire(import.meta.url);
const { parse, parseModule } = require('../src/index.js');
const esModuleLexer = require('es-module-lexer');

// 1. parse is exported as a function from es-module-lexer
assert.strictEqual(typeof parse, 'function', 'parse must be a function');
assert.strictEqual(parse, esModuleLexer.parse, 'parse must match es-module-lexer.parse export');

// 2. parse extracts static imports and named exports with specifier names and position ranges
const codeWithStaticImportsExports = `
  import defaultItem, { itemA, itemB as renamedB } from 'pkg-dep';
  export const value = 42;
  export function helper() {}
  export { renamedB as publicExport };
  export default 100;
`;
const [imports1, exports1, facade1, hasModuleSyntax1] = await parseModule(codeWithStaticImportsExports);

assert.strictEqual(imports1.length, 1, 'must detect 1 static import statement');
assert.strictEqual(imports1[0].n, 'pkg-dep', 'import specifier should match');
assert.strictEqual(imports1[0].d, -1, 'static import has dynamic index -1');
assert.strictEqual(
  codeWithStaticImportsExports.slice(imports1[0].s, imports1[0].e),
  'pkg-dep',
  'import specifier start and end indices must match slice'
);

assert.strictEqual(exports1.length, 4, 'must detect 4 export statements');
const exportNames = exports1.map((e) => e.n);
assert.deepStrictEqual(exportNames, ['value', 'helper', 'publicExport', 'default']);
assert.strictEqual(facade1, false, 'module with local code is not facade');
assert.strictEqual(hasModuleSyntax1, true, 'module with imports/exports hasModuleSyntax=true');

// 3. parse detects dynamic import calls and import.meta expressions
const codeWithDynamicImport = `
  const lazyModule = import('lazy-module');
  const currentUrl = import.meta.url;
`;
const [imports2, exports2, facade2, hasModuleSyntax2] = await parseModule(codeWithDynamicImport);

assert.strictEqual(imports2.length, 2, 'must detect dynamic import and import.meta');
assert.strictEqual(imports2[0].n, 'lazy-module', 'dynamic import specifier should match');
assert.ok(imports2[0].d >= 0, 'dynamic import index must be non-negative start index');
assert.strictEqual(imports2[1].d, -2, 'import.meta index must be -2');
assert.strictEqual(exports2.length, 0, 'no exports in dynamic import snippet');
assert.strictEqual(hasModuleSyntax2, true, 'dynamic import / import.meta hasModuleSyntax=true');

// 4. parse identifies facade re-export modules and distinguishes ESM from plain scripts
const facadeCode = `export * from 'other-module';`;
const [importsFacade, exportsFacade, isFacade, hasSyntaxFacade] = await parseModule(facadeCode);
assert.strictEqual(importsFacade.length, 1);
assert.strictEqual(importsFacade[0].n, 'other-module');
assert.strictEqual(isFacade, true, 'pure export * is a facade module');
assert.strictEqual(hasSyntaxFacade, true);

const plainScript = `const a = 10; const b = 20; console.log(a + b);`;
const [importsScript, exportsScript, isFacadeScript, hasSyntaxScript] = await parseModule(plainScript);
assert.strictEqual(importsScript.length, 0);
assert.strictEqual(exportsScript.length, 0);
assert.strictEqual(isFacadeScript, false);
assert.strictEqual(hasSyntaxScript, false, 'plain script without module statements hasModuleSyntax=false');

console.log('All parse contract assertions passed.');