TypeError: Cannot read property 'length' of undefined

[alexander-akait]

• A little info about your environment
  • npm-package-json-lint version 2.8.0
  • npm version 5.3.0
  • node version 8.4.0
• The output from npm-package-json-lint

TypeError: Cannot read property 'length' of undefined
/path/to/node_modules/npm-package-json-lint/src/cli.js:28
  throw new Error(err);
  ^

Error: TypeError: Cannot read property 'length' of undefined
    at handleError (/path/to/node_modules/npm-package-json-lint/src/cli.js:28:9)
    at Object.<anonymous> (/path/to/node_modules/npm-package-json-lint/src/cli.js:126:3)
    at Module._compile (module.js:573:30)
    at Object.Module._extensions..js (module.js:584:10)
    at Module.load (module.js:507:32)
    at tryModuleLoad (module.js:470:12)
    at Function.Module._load (module.js:462:3)
    at Function.Module.runMain (module.js:609:10)
    at startup (bootstrap_node.js:158:16)
    at bootstrap_node.js:598:3

• What you expected to happen
  Not throw error.
• The steps to reproduce the problem

1. Create npmpackagejsonlint.config.js with prefer-property-order rule.

module.exports = {
  rules: {
    "prefer-property-order": ["error", [
      "name",
      "version",
      "description",
      "keywords",
      "homepage",
      "bugs",
      "license",
      "author",
      "contributors",
      "files",
      "main",
      "jsnext:main",
      "bin",
      "man",
      "directories",
      "repository",
      "scripts",
      "config",
      "dependencies",
      "devDependencies",
      "peerDependencies",
      "bundleDependencies",
      "bundledDependencies",
      "optionalDependencies",
      "engines",
      "engineStrict",
      "os",
      "cpu",
      "preferGlobal",
      "private",
      "publishConfig"
    ]]
  }
};

2. Create package.json.

{
  "name": "test",
  "version": "0.0.4",
  "description": "test"
}

[tclindner]

Thank you for catching this, @evilebottnawi! I've release v2.8.1. It should address your issue. It also contains feedback from #50. Let me know what you think.

[alexander-akait]

@tclindner problem still exists 😞 use post above to reproducible error.
In function(packageJsonData, lintType, preferredOrder) preferredOrder contains undefined, but lintType containts

[ 'error',
  [ 'name',
    'version',
    'description',
    'keywords',
    'homepage',
    'bugs',
    'license',
    'author',
    'contributors',
    'files',
    'main',
    'jsnext:main',
    'bin',
    'man',
    'directories',
    'repository',
    'scripts',
    'config',
    'dependencies',
    'devDependencies',
    'peerDependencies',
    'bundleDependencies',
    'bundledDependencies',
    'optionalDependencies',
    'engines',
    'engineStrict',
    'os',
    'cpu',
    'preferGlobal',
    'private',
    'publishConfig' ] ]

[tclindner]

I'm so sorry about that @evilebottnawi! I believe I have identified the issue. The rules loader was not properly interpreting this rule as a "array" type rule. I've released v2.8.2 to address that. Can you please try it out and see if it resolves your issue? Sorry again about the issues with this rule.

P.S. I will be logging an enhancement to improve the rules loader to avoid hitting this issue in the future. I'll tag you on that ticket. Thank you again for helping improve this project 🥇