chenglou/pretext · error · Error

Unexpected TypeScript consumer error output

Error message

Unexpected TypeScript consumer error output:
${combinedOutput}

What it means

smokeTypeScript()'s negative case correctly failed (tsc exit non-zero), but the emitted error text did not contain either of the two expected 'not assignable to parameter of type number' / 'not assignable to type number' substrings. This means a different error surfaced first, or the TS error wording changed across versions.

Solutions

1. Read the full combinedOutput printed in the error to see which TS diagnostic fired.
2. If module/type resolution failed first, ensure the tarball installs the .d.ts files and the consumer tsconfig resolves '@chenglou/pretext'.
3. If TS reworded the message, add the new wording to the accepted-substrings check at scripts/package-smoke-test.ts:140 or pin the TS version.

try {
  // negative compile step
} catch (e) {
  const msg = e instanceof Error ? e.message : String(e)
  if (msg.includes('Unexpected TypeScript consumer error output')) {
    console.error('TS error wording changed or a different error fired first. Full output:\n' + msg)
    process.exit(1)
  }
  throw e
}

When it happens

Trigger: A newer TypeScript version reworded the assignment-error message; or the invalid program failed for a different reason (e.g. module resolution, missing types) before reaching the layout() call's type error.

Common situations: Upgrading TypeScript in the repo; the package's declarations not resolving in the consumer project so a 'cannot find module' error fires first.

Related errors

• Expected TypeScript consumer misuse to fail, but it…
• Command failed ( )
• Expected exactly one tarball in
• Invalid value for
• Invalid value for

AI-assisted analysis of chenglou/pretext@ac49b09b7d (2026-08-12). Data as JSON: /api/errors/7845628bb59f2654. Report an issue: GitHub.

Appendix: source

Thrown at scripts/package-smoke-test.ts:144

    [path.join(root, 'node_modules', '.bin', tscBinaryName()), '-p', 'tsconfig.json'],
    {
      cwd: projectDir,
      stdout: 'pipe',
      stderr: 'pipe',
      allowFailure: true,
    },
  )

  if (badCompile.exitCode === 0) {
    throw new Error('Expected TypeScript consumer misuse to fail, but it compiled successfully.')
  }

  const combinedOutput = `${badCompile.stdout}${badCompile.stderr}`
  if (
    !combinedOutput.includes("Argument of type 'string' is not assignable to parameter of type 'number'.") &&
    !combinedOutput.includes("Type 'string' is not assignable to type 'number'.")
  ) {
    throw new Error(`Unexpected TypeScript consumer error output:\n${combinedOutput}`)
  }

  console.log('ts ok')
}

async function createProject(dir: string, pkg: Record<string, unknown>): Promise<void> {
  await mkdir(dir, { recursive: true })
  await writeFile(path.join(dir, 'package.json'), JSON.stringify(pkg, null, 2) + '\n')
}

async function installTarball(projectDir: string, tarballPath: string): Promise<void> {
  run(['npm', 'install', '--ignore-scripts', '--no-package-lock', tarballPath], {
    cwd: projectDir,
    stdout: 'inherit',
    stderr: 'inherit',
  })
}

View on GitHub (pinned to ac49b09b7d)