escodegen 2.1.0: generate

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 escodegen.generate in pkg:npm/escodegen@2.1.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/escodegen@2.1.0
Demonstrate these symbols/APIs:
  - escodegen.generate

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:sha256:24c86bfbf58855c1faf68e94aea938f9f4583065a324c253b9be1980d3c2ee9b","contract":["escodegen.generate is exported as a function","generate produces JavaScript code string from standard AST Program and VariableDeclaration nodes","generate produces code for binary expressions and function calls","generate respects format options such as semicolons and compact output"],"goal":"verify escodegen.generate in pkg:npm/escodegen@2.1.0","kind":"HOW","packages":["pkg:npm/escodegen@2.1.0"],"schemaVersion":1,"symbols":["escodegen.generate"]},"contractCommand":["node","test/contract.mjs"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"npm","executionContext":"node","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/escodegen@2.1.0"],"schemaVersion":1,"subject":"pkg:npm/escodegen@2.1.0","symbols":["escodegen.generate"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-escodegen-generate",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-escodegen-generate",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "escodegen": "2.1.0"
      }
    },
    "node_modules/escodegen": {
      "version": "2.1.0",
      "resolved": "https://registry.npmjs.org/escodegen/-/escodegen-2.1.0.tgz",
      "integrity": "sha512-2NlIDTwUWJN0mRPQOdtQBzbUHvdGY2P1VXSyU83Q3xKxM7WHX2Ql8dKq782Q9TgQUNOLEzEYu9bzLNj1q88I5w==",
      "license": "BSD-2-Clause",
      "dependencies": {
        "esprima": "^4.0.1",
        "estraverse": "^5.2.0",
        "esutils": "^2.0.2"
      },
      "bin": {
        "escodegen": "bin/escodegen.js",
        "esgenerate": "bin/esgenerate.js"
      },
      "engines": {
        "node": ">=6.0"
      },
      "optionalDependencies": {
        "source-map": "~0.6.1"
      }
    },
    "node_modules/esprima": {
      "version": "4.0.1",
      "resolved": "https://registry.npmjs.org/esprima/-/esprima-4.0.1.tgz",
      "integrity": "sha512-eGuFFw7Upda+g4p+QHvnW0RyTX/SVeJBDM/gCtMARO0cLuT2HcEKnTPvhjV6aGeqrCB/sbNop0Kszm0jsaWU4A==",
      "license": "BSD-2-Clause",
      "bin": {
        "esparse": "bin/esparse.js",
        "esvalidate": "bin/esvalidate.js"
      },
      "engines": {
        "node": ">=4"
      }
    },
    "node_modules/estraverse": {
      "version": "5.3.0",
      "resolved": "https://registry.npmjs.org/estraverse/-/estraverse-5.3.0.tgz",
      "integrity": "sha512-MMdARuVEQziNTeJD8DgMqmhwR11BRQ/cBP+pLtYdSTnf3MIO8fFeiINEbX36ZdNlfU/7A9f3gUw49B3oQsvwBA==",
      "license": "BSD-2-Clause",
      "engines": {
        "node": ">=4.0"
      }
    },
    "node_modules/esutils": {
      "version": "2.0.3",
      "resolved": "https://registry.npmjs.org/esutils/-/esutils-2.0.3.tgz",
      "integrity": "sha512-kVscqXk4OCp68SZ0dkgEKVi6/8ij300KBWTJq32P/dYeWTSwK41WyTxalN1eRmA5Z9UU/LX9D7FWSmV9SAYx6g==",
      "license": "BSD-2-Clause",
      "engines": {
        "node": ">=0.10.0"
      }
    },
    "node_modules/source-map": {
      "version": "0.6.1",
      "resolved": "https://registry.npmjs.org/source-map/-/source-map-0.6.1.tgz",
      "integrity": "sha512-UjgapumWlbMhkBgzT7Ykc5YXUT46F0iKu8SGXq0bcwP5dz/h0Plj6enJqjz1Zbq2l5WaqYnrVbwWOWMyF3F47g==",
      "license": "BSD-3-Clause",
      "optional": true,
      "engines": {
        "node": ">=0.10.0"
      }
    }
  }
}

{
  "name": "sample-escodegen-generate",
  "version": "1.0.0",
  "private": true,
  "description": "verify escodegen.generate in pkg:npm/escodegen@2.1.0",
  "main": "src/index.js",
  "license": "MIT-0",
  "dependencies": {
    "escodegen": "2.1.0"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify escodegen.generate in pkg:npm/escodegen@2.1.0",
  "kind": "HOW",
  "packages": [
    "pkg:npm/escodegen@2.1.0"
  ],
  "symbols": [
    "escodegen.generate"
  ]
}

const escodegen = require('escodegen');

/**
 * Generates JavaScript code from an ESTree-compatible Abstract Syntax Tree.
 * @param {object} ast - The AST node or program to generate code from.
 * @param {object} [options] - Formatting and generation options.
 * @returns {string} The generated JavaScript source code.
 */
function generateCode(ast, options) {
  return escodegen.generate(ast, options);
}

/**
 * Generates a variable declaration statement AST and converts it to code.
 * @param {string} kind - 'var', 'let', or 'const'.
 * @param {string} name - Variable name identifier.
 * @param {any} value - Literal value.
 * @param {object} [options] - Formatting options.
 * @returns {string} Generated JavaScript code.
 */
function generateVariable(kind, name, value, options) {
  const ast = {
    type: 'VariableDeclaration',
    kind: kind,
    declarations: [
      {
        type: 'VariableDeclarator',
        id: { type: 'Identifier', name: name },
        init: { type: 'Literal', value: value, raw: JSON.stringify(value) }
      }
    ]
  };
  return escodegen.generate(ast, options);
}

module.exports = {
  generateCode,
  generateVariable,
  generate: escodegen.generate
};

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

const require = createRequire(import.meta.url);
const escodegen = require('escodegen');
const { generateCode, generateVariable, generate } = require('../src/index.js');

// 1. Verify escodegen.generate is exported and callable
assert.strictEqual(typeof escodegen.generate, 'function', 'escodegen.generate must be a function');
assert.strictEqual(generate, escodegen.generate, 'exported generate must match escodegen.generate');

// 2. generate produces JavaScript code string from standard AST Program and VariableDeclaration nodes
const programAst = {
  type: 'Program',
  body: [
    {
      type: 'VariableDeclaration',
      kind: 'const',
      declarations: [
        {
          type: 'VariableDeclarator',
          id: { type: 'Identifier', name: 'greeting' },
          init: { type: 'Literal', value: 'Hello, World!', raw: "'Hello, World!'" }
        }
      ]
    }
  ],
  sourceType: 'script'
};
const codeFromProgram = generateCode(programAst);
assert.strictEqual(codeFromProgram.trim(), "const greeting = 'Hello, World!';");

const varCode = generateVariable('let', 'count', 42);
assert.strictEqual(varCode.trim(), 'let count = 42;');

// 3. generate produces code for binary expressions and function calls
const binaryAst = {
  type: 'BinaryExpression',
  operator: '+',
  left: { type: 'Literal', value: 40, raw: '40' },
  right: { type: 'Literal', value: 2, raw: '2' }
};
const binaryCode = generateCode(binaryAst);
assert.strictEqual(binaryCode.trim(), '40 + 2');

const callAst = {
  type: 'CallExpression',
  callee: { type: 'Identifier', name: 'calculate' },
  arguments: [
    { type: 'Literal', value: 10, raw: '10' },
    { type: 'Literal', value: 20, raw: '20' }
  ]
};
const callCode = generateCode(callAst);
assert.strictEqual(callCode.trim(), 'calculate(10, 20)');

// 4. generate respects format options such as semicolons and compact output
const noSemicolonCode = generateCode(programAst, {
  format: {
    semicolons: false
  }
});
assert.strictEqual(noSemicolonCode.trim(), "const greeting = 'Hello, World!'");

const compactCode = generateCode(programAst, {
  format: {
    compact: true
  }
});
assert.strictEqual(compactCode.trim(), "const greeting='Hello, World!';");

console.log('Contract assertions passed.');