old_contents: 'use strict';
  var isPotentialCustomElementName = require('is-potential-custom-element-name');
  
  // https://html.spec.whatwg.org/multipage/scripting.html#valid-custom-element-name
  var reservedNames = [
  	'annotation-xml',
  	'color-profile',
  	'font-face',
  	'font-face-src',
  	'font-face-uri',
  	'font-face-format',
  	'font-face-name',
  	'missing-glyph'
  ];
  
  function hasError(name) {
  	if (!name) {
  		return 'Missing element name.';
  	}
  
  	if (/[A-Z]/.test(name)) {
  		return 'Custom element names must not contain uppercase ASCII characters.';
  	}
  
  	if (name.indexOf('-') === -1) {
  		return 'Custom element names must contain a hyphen. Example: unicorn-cake';
  	}
  
  	if (/^\d/i.test(name)) {
  		return 'Custom element names must not start with a digit.';
  	}
  
  	if (/^-/i.test(name)) {
  		return 'Custom element names must not start with a hyphen.';
  	}
  
  	// https://html.spec.whatwg.org/multipage/scripting.html#prod-potentialcustomelementname
  	if (!isPotentialCustomElementName(name)) {
  		return 'Invalid element name.';
  	}
  
  	if (reservedNames.indexOf(name) !== -1) {
  		return 'The supplied element name is reserved and can\'t be used.\nSee: https://html.spec.whatwg.org/multipage/scripting.html#valid-custom-element-name';
  	}
  }
  
  function hasWarning(name) {
  	if (/^polymer-/i.test(name)) {
  		return 'Custom element names should not start with `polymer-`.\nSee: http://webcomponents.github.io/articles/how-should-i-name-my-element';
  	}
  
  	if (/^x-/i.test(name)) {
  		return 'Custom element names should not start with `x-`.\nSee: http://webcomponents.github.io/articles/how-should-i-name-my-element/';
  	}
  
  	if (/^ng-/i.test(name)) {
  		return 'Custom element names should not start with `ng-`.\nSee: http://docs.angularjs.org/guide/directive#creating-directives';
  	}
  
  	if (/^xml/i.test(name)) {
  		return 'Custom element names should not start with `xml`.';
  	}
  
  	if (/^[^a-z]/i.test(name)) {
  		return 'This element name is only valid in XHTML, not in HTML. First character should be in the range a-z.';
  	}
  
  	if (/-$/.test(name)) {
  		return 'Custom element names should not end with an hyphen.';
  	}
  
  	if (/[\.]/.test(name)) {
  		return 'Custom element names should not contain a dot character as it would need to be escaped in a CSS selector.';
  	}
  
  	if (/[^\x20-\x7E]/.test(name)) {
  		return 'Custom element names should not contain non-ASCII characters.';
  	}
  
  	if (/--/.test(name)) {
  		return 'Custom element names should not contain consecutive hyphens.';
  	}
  
  	if (/[^a-z0-9]{2}/i.test(name)) {
  		return 'Custom element names should not contain consecutive non-alpha characters.';
  	}
  }
  
  module.exports = function (name) {
  	var errMsg = hasError(name);
  
  	return {
  		isValid: !errMsg,
  		message: errMsg || hasWarning(name)
  	};
  };
  
new_contents: 'use strict';
  var isPotentialCustomElementName = require('is-potential-custom-element-name');
  
  // https://html.spec.whatwg.org/multipage/scripting.html#valid-custom-element-name
  var reservedNames = [
  	'annotation-xml',
  	'color-profile',
  	'font-face',
  	'font-face-src',
  	'font-face-uri',
  	'font-face-format',
  	'font-face-name',
  	'missing-glyph'
  ];
  
  function hasError(name) {
  	if (!name) {
  		return 'Missing element name.';
  	}
  
  	if (/[A-Z]/.test(name)) {
  		return 'Custom element names must not contain uppercase ASCII characters.';
  	}
  
  	if (name.indexOf('-') === -1) {
  		return 'Custom element names must contain a hyphen. Example: unicorn-cake';
  	}
  
  	if (/^\d/i.test(name)) {
  		return 'Custom element names must not start with a digit.';
  	}
  
  	if (/^-/i.test(name)) {
  		return 'Custom element names must not start with a hyphen.';
  	}
  
  	// https://html.spec.whatwg.org/multipage/scripting.html#prod-potentialcustomelementname
  	if (!isPotentialCustomElementName(name)) {
  		return 'Invalid element name.';
  	}
  
  	if (reservedNames.indexOf(name) !== -1) {
  		return 'The supplied element name is reserved and can\'t be used.\nSee: https://html.spec.whatwg.org/multipage/scripting.html#valid-custom-element-name';
  	}
  }
  
  function hasWarning(name) {
  	if (/^polymer-/i.test(name)) {
  		return 'Custom element names should not start with `polymer-`.\nSee: http://webcomponents.github.io/articles/how-should-i-name-my-element';
  	}
  
  	if (/^x-/i.test(name)) {
  		return 'Custom element names should not start with `x-`.\nSee: http://webcomponents.github.io/articles/how-should-i-name-my-element/';
  	}
  
  	if (/^ng-/i.test(name)) {
  		return 'Custom element names should not start with `ng-`.\nSee: http://docs.angularjs.org/guide/directive#creating-directives';
  	}
  
  	if (/^xml/i.test(name)) {
  		return 'Custom element names should not start with `xml`.';
  	}
  
  	if (/^[^a-z]/i.test(name)) {
  		return 'This element name is only valid in XHTML, not in HTML. First character should be in the range a-z.';
  	}
  
  	if (/-$/.test(name)) {
  		return 'Custom element names should not end with a hyphen.';
  	}
  
  	if (/[\.]/.test(name)) {
  		return 'Custom element names should not contain a dot character as it would need to be escaped in a CSS selector.';
  	}
  
  	if (/[^\x20-\x7E]/.test(name)) {
  		return 'Custom element names should not contain non-ASCII characters.';
  	}
  
  	if (/--/.test(name)) {
  		return 'Custom element names should not contain consecutive hyphens.';
  	}
  
  	if (/[^a-z0-9]{2}/i.test(name)) {
  		return 'Custom element names should not contain consecutive non-alpha characters.';
  	}
  }
  
  module.exports = function (name) {
  	var errMsg = hasError(name);
  
  	return {
  		isValid: !errMsg,
  		message: errMsg || hasWarning(name)
  	};
  };
  
subject: fix typo