lint: validate readme constructor list

Author: dougwilson

package.json

@@ -31,7 +31,7 @@
     "node": ">= 0.6"
   },
   "scripts": {
-    "lint": "eslint --plugin markdown --ext js,md .",
+    "lint": "eslint --plugin markdown --ext js,md . && node ./scripts/lint-readme-list.js",
     "test": "mocha --reporter spec --bail",
     "test-cov": "istanbul cover node_modules/mocha/bin/_mocha -- --reporter dot",
     "test-travis": "istanbul cover node_modules/mocha/bin/_mocha --report lcovonly -- --reporter dot"

scripts/lint-readme-list.js

@@ -0,0 +1,30 @@
+var assert = require('assert')
+var createError = require('..')
+var fs = require('fs')
+var path = require('path')
+var util = require('util')
+
+var README_PATH = path.join(__dirname, '..', 'README.md')
+var README_CONTENTS = fs.readFileSync(README_PATH, 'utf-8')
+
+for (var key in createError) {
+  if (!createError.hasOwnProperty(key)) {
+    continue
+  }
+
+  if (!isNaN(key)) {
+    continue
+  }
+
+  var constructor = createError[key]
+  var statusCode = constructor.prototype.statusCode
+
+  if (createError[statusCode] !== constructor) {
+    continue
+  }
+
+  var regexp = new RegExp(util.format('^\\|%d\\s*\\|%s\\s*\\|$', statusCode, key), 'm')
+
+  assert.ok(regexp.test(README_CONTENTS),
+    util.format('README constructor list contains %d %s', statusCode, key))
+}