esbuild 0.21.5

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 pkg:npm/esbuild@0.21.5
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/esbuild@0.21.5

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:sha256:67a80d911c90beec2b792f97a9663d6f9c6c31d053d3a7004f3af5abe17c3ddd","contract":["esbuild.buildSync bundles TypeScript source code into CommonJS JavaScript in memory","esbuild.transformSync transpiles TypeScript code and JSX syntax to plain JavaScript with minification","esbuild.formatMessagesSync formats diagnostic error messages with file location and source line context","esbuild.analyzeMetafileSync computes formatted bundle breakdown from build metafile"],"goal":"verify pkg:npm/esbuild@0.21.5","kind":"HOW","packages":["pkg:npm/esbuild@0.21.5"],"schemaVersion":1},"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/esbuild@0.21.5"],"schemaVersion":1,"subject":"pkg:npm/esbuild@0.21.5","verifierAdapter":"node-typescript@1"}

{
  "name": "sample-esbuild",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-esbuild",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "esbuild": "0.21.5"
      }
    },
    "node_modules/@esbuild/aix-ppc64": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/aix-ppc64/-/aix-ppc64-0.21.5.tgz",
      "integrity": "sha512-1SDgH6ZSPTlggy1yI6+Dbkiz8xzpHJEVAlF/AM1tHPLsf5STom9rwtjE4hKAF20FfXXNTFqEYXyJNWh1GiZedQ==",
      "cpu": [
        "ppc64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "aix"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/android-arm": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/android-arm/-/android-arm-0.21.5.tgz",
      "integrity": "sha512-vCPvzSjpPHEi1siZdlvAlsPxXl7WbOVUBBAowWug4rJHb68Ox8KualB+1ocNvT5fjv6wpkX6o/iEpbDrf68zcg==",
      "cpu": [
        "arm"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "android"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/android-arm64": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/android-arm64/-/android-arm64-0.21.5.tgz",
      "integrity": "sha512-c0uX9VAUBQ7dTDCjq+wdyGLowMdtR/GoC2U5IYk/7D1H1JYC0qseD7+11iMP2mRLN9RcCMRcjC4YMclCzGwS/A==",
      "cpu": [
        "arm64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "android"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/android-x64": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/android-x64/-/android-x64-0.21.5.tgz",
      "integrity": "sha512-D7aPRUUNHRBwHxzxRvp856rjUHRFW1SdQATKXH2hqA0kAZb1hKmi02OpYRacl0TxIGz/ZmXWlbZgjwWYaCakTA==",
      "cpu": [
        "x64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "android"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/darwin-arm64": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/darwin-arm64/-/darwin-arm64-0.21.5.tgz",
      "integrity": "sha512-DwqXqZyuk5AiWWf3UfLiRDJ5EDd49zg6O9wclZ7kUMv2WRFr4HKjXp/5t8JZ11QbQfUS6/cRCKGwYhtNAY88kQ==",
      "cpu": [
        "arm64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "darwin"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/darwin-x64": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/darwin-x64/-/darwin-x64-0.21.5.tgz",
      "integrity": "sha512-se/JjF8NlmKVG4kNIuyWMV/22ZaerB+qaSi5MdrXtd6R08kvs2qCN4C09miupktDitvh8jRFflwGFBQcxZRjbw==",
      "cpu": [
        "x64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "darwin"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/freebsd-arm64": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/freebsd-arm64/-/freebsd-arm64-0.21.5.tgz",
      "integrity": "sha512-5JcRxxRDUJLX8JXp/wcBCy3pENnCgBR9bN6JsY4OmhfUtIHe3ZW0mawA7+RDAcMLrMIZaf03NlQiX9DGyB8h4g==",
      "cpu": [
        "arm64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "freebsd"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/freebsd-x64": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/freebsd-x64/-/freebsd-x64-0.21.5.tgz",
      "integrity": "sha512-J95kNBj1zkbMXtHVH29bBriQygMXqoVQOQYA+ISs0/2l3T9/kj42ow2mpqerRBxDJnmkUDCaQT/dfNXWX/ZZCQ==",
      "cpu": [
        "x64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "freebsd"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/linux-arm": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/linux-arm/-/linux-arm-0.21.5.tgz",
      "integrity": "sha512-bPb5AHZtbeNGjCKVZ9UGqGwo8EUu4cLq68E95A53KlxAPRmUyYv2D6F0uUI65XisGOL1hBP5mTronbgo+0bFcA==",
      "cpu": [
        "arm"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "linux"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/linux-arm64": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/linux-arm64/-/linux-arm64-0.21.5.tgz",
      "integrity": "sha512-ibKvmyYzKsBeX8d8I7MH/TMfWDXBF3db4qM6sy+7re0YXya+K1cem3on9XgdT2EQGMu4hQyZhan7TeQ8XkGp4Q==",
      "cpu": [
        "arm64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "linux"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/linux-ia32": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/linux-ia32/-/linux-ia32-0.21.5.tgz",
      "integrity": "sha512-YvjXDqLRqPDl2dvRODYmmhz4rPeVKYvppfGYKSNGdyZkA01046pLWyRKKI3ax8fbJoK5QbxblURkwK/MWY18Tg==",
      "cpu": [
        "ia32"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "linux"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/linux-loong64": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/linux-loong64/-/linux-loong64-0.21.5.tgz",
      "integrity": "sha512-uHf1BmMG8qEvzdrzAqg2SIG/02+4/DHB6a9Kbya0XDvwDEKCoC8ZRWI5JJvNdUjtciBGFQ5PuBlpEOXQj+JQSg==",
      "cpu": [
        "loong64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "linux"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/linux-mips64el": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/linux-mips64el/-/linux-mips64el-0.21.5.tgz",
      "integrity": "sha512-IajOmO+KJK23bj52dFSNCMsz1QP1DqM6cwLUv3W1QwyxkyIWecfafnI555fvSGqEKwjMXVLokcV5ygHW5b3Jbg==",
      "cpu": [
        "mips64el"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "linux"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/linux-ppc64": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/linux-ppc64/-/linux-ppc64-0.21.5.tgz",
      "integrity": "sha512-1hHV/Z4OEfMwpLO8rp7CvlhBDnjsC3CttJXIhBi+5Aj5r+MBvy4egg7wCbe//hSsT+RvDAG7s81tAvpL2XAE4w==",
      "cpu": [
        "ppc64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "linux"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/linux-riscv64": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/linux-riscv64/-/linux-riscv64-0.21.5.tgz",
      "integrity": "sha512-2HdXDMd9GMgTGrPWnJzP2ALSokE/0O5HhTUvWIbD3YdjME8JwvSCnNGBnTThKGEB91OZhzrJ4qIIxk/SBmyDDA==",
      "cpu": [
        "riscv64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "linux"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/linux-s390x": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/linux-s390x/-/linux-s390x-0.21.5.tgz",
      "integrity": "sha512-zus5sxzqBJD3eXxwvjN1yQkRepANgxE9lgOW2qLnmr8ikMTphkjgXu1HR01K4FJg8h1kEEDAqDcZQtbrRnB41A==",
      "cpu": [
        "s390x"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "linux"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/linux-x64": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/linux-x64/-/linux-x64-0.21.5.tgz",
      "integrity": "sha512-1rYdTpyv03iycF1+BhzrzQJCdOuAOtaqHTWJZCWvijKD2N5Xu0TtVC8/+1faWqcP9iBCWOmjmhoH94dH82BxPQ==",
      "cpu": [
        "x64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "linux"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/netbsd-x64": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/netbsd-x64/-/netbsd-x64-0.21.5.tgz",
      "integrity": "sha512-Woi2MXzXjMULccIwMnLciyZH4nCIMpWQAs049KEeMvOcNADVxo0UBIQPfSmxB3CWKedngg7sWZdLvLczpe0tLg==",
      "cpu": [
        "x64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "netbsd"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/openbsd-x64": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/openbsd-x64/-/openbsd-x64-0.21.5.tgz",
      "integrity": "sha512-HLNNw99xsvx12lFBUwoT8EVCsSvRNDVxNpjZ7bPn947b8gJPzeHWyNVhFsaerc0n3TsbOINvRP2byTZ5LKezow==",
      "cpu": [
        "x64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "openbsd"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/sunos-x64": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/sunos-x64/-/sunos-x64-0.21.5.tgz",
      "integrity": "sha512-6+gjmFpfy0BHU5Tpptkuh8+uw3mnrvgs+dSPQXQOv3ekbordwnzTVEb4qnIvQcYXq6gzkyTnoZ9dZG+D4garKg==",
      "cpu": [
        "x64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "sunos"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/win32-arm64": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/win32-arm64/-/win32-arm64-0.21.5.tgz",
      "integrity": "sha512-Z0gOTd75VvXqyq7nsl93zwahcTROgqvuAcYDUr+vOv8uHhNSKROyU961kgtCD1e95IqPKSQKH7tBTslnS3tA8A==",
      "cpu": [
        "arm64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "win32"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/win32-ia32": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/win32-ia32/-/win32-ia32-0.21.5.tgz",
      "integrity": "sha512-SWXFF1CL2RVNMaVs+BBClwtfZSvDgtL//G/smwAc5oVK/UPu2Gu9tIaRgFmYFFKrmg3SyAjSrElf0TiJ1v8fYA==",
      "cpu": [
        "ia32"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "win32"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/@esbuild/win32-x64": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/@esbuild/win32-x64/-/win32-x64-0.21.5.tgz",
      "integrity": "sha512-tQd/1efJuzPC6rCFwEvLtci/xNFcTZknmXs98FYDfGE4wP9ClFV98nyKrzJKVPMhdDnjzLhdUyMX4PsQAPjwIw==",
      "cpu": [
        "x64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "win32"
      ],
      "engines": {
        "node": ">=12"
      }
    },
    "node_modules/esbuild": {
      "version": "0.21.5",
      "resolved": "https://registry.npmjs.org/esbuild/-/esbuild-0.21.5.tgz",
      "integrity": "sha512-mg3OPMV4hXywwpoDxu3Qda5xCKQi+vCTZq8S9J/EpkhB2HzKXq4SNFZE3+NK93JYxc8VMSep+lOUSC/RVKaBqw==",
      "hasInstallScript": true,
      "license": "MIT",
      "bin": {
        "esbuild": "bin/esbuild"
      },
      "engines": {
        "node": ">=12"
      },
      "optionalDependencies": {
        "@esbuild/aix-ppc64": "0.21.5",
        "@esbuild/android-arm": "0.21.5",
        "@esbuild/android-arm64": "0.21.5",
        "@esbuild/android-x64": "0.21.5",
        "@esbuild/darwin-arm64": "0.21.5",
        "@esbuild/darwin-x64": "0.21.5",
        "@esbuild/freebsd-arm64": "0.21.5",
        "@esbuild/freebsd-x64": "0.21.5",
        "@esbuild/linux-arm": "0.21.5",
        "@esbuild/linux-arm64": "0.21.5",
        "@esbuild/linux-ia32": "0.21.5",
        "@esbuild/linux-loong64": "0.21.5",
        "@esbuild/linux-mips64el": "0.21.5",
        "@esbuild/linux-ppc64": "0.21.5",
        "@esbuild/linux-riscv64": "0.21.5",
        "@esbuild/linux-s390x": "0.21.5",
        "@esbuild/linux-x64": "0.21.5",
        "@esbuild/netbsd-x64": "0.21.5",
        "@esbuild/openbsd-x64": "0.21.5",
        "@esbuild/sunos-x64": "0.21.5",
        "@esbuild/win32-arm64": "0.21.5",
        "@esbuild/win32-ia32": "0.21.5",
        "@esbuild/win32-x64": "0.21.5"
      }
    }
  }
}

{
  "name": "sample-esbuild",
  "version": "1.0.0",
  "type": "module",
  "private": true,
  "license": "MIT-0",
  "dependencies": {
    "esbuild": "0.21.5"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify pkg:npm/esbuild@0.21.5",
  "kind": "HOW",
  "packages": [
    "pkg:npm/esbuild@0.21.5"
  ]
}

import * as esbuild from 'esbuild';
import assert from 'node:assert';

// 1. esbuild.buildSync bundles TypeScript source code into CommonJS JavaScript in memory
const buildResult = esbuild.buildSync({
  stdin: {
    contents: 'const val: number = 42; module.exports = { val };',
    resolveDir: process.cwd(),
    loader: 'ts',
  },
  bundle: true,
  write: false,
  format: 'cjs',
  metafile: true,
});
assert.strictEqual(buildResult.errors.length, 0);
assert.strictEqual(buildResult.outputFiles.length, 1);
const bundledText = Buffer.from(buildResult.outputFiles[0].contents).toString('utf-8');
assert.ok(bundledText.includes('42'));
assert.ok(!bundledText.includes(': number'));

// 2. esbuild.transformSync transpiles TypeScript code and JSX syntax to plain JavaScript with minification
const transformResult = esbuild.transformSync('const App = () => <div><h1>Hello</h1></div>;', {
  loader: 'jsx',
  minify: true,
});
assert.strictEqual(transformResult.warnings.length, 0);
assert.ok(typeof transformResult.code === 'string');
assert.ok(transformResult.code.length > 0);
assert.ok(transformResult.code.includes('React.createElement'));

// 3. esbuild.formatMessagesSync formats diagnostic error messages with file location and source line context
const formatted = esbuild.formatMessagesSync([
  {
    text: 'Type mismatch error',
    location: {
      file: 'src/index.ts',
      line: 10,
      column: 4,
      length: 5,
      lineText: 'let a: string = 123;',
    },
  },
], {
  kind: 'error',
  color: false,
});
assert.strictEqual(formatted.length, 1);
assert.ok(formatted[0].includes('src/index.ts:10:4'));
assert.ok(formatted[0].includes('Type mismatch error'));

// 4. esbuild.analyzeMetafileSync computes formatted bundle breakdown from build metafile
assert.ok(buildResult.metafile);
const analysis = esbuild.analyzeMetafileSync(buildResult.metafile);
assert.ok(typeof analysis === 'string');
assert.ok(analysis.length > 0);

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