var escapeCharacters = function()

in assets/js/plugins/smooth-scroll.js [115:187]
44 lines of code
23 McCabe index (conditional complexity)

	var escapeCharacters = function (id) {

		// Remove leading hash
		if (id.charAt(0) === '#') {
			id = id.substr(1);
		}

		var string = String(id);
		var length = string.length;
		var index = -1;
		var codeUnit;
		var result = '';
		var firstCodeUnit = string.charCodeAt(0);
		while (++index < length) {
			codeUnit = string.charCodeAt(index);
			// Note: there’s no need to special-case astral symbols, surrogate
			// pairs, or lone surrogates.

			// If the character is NULL (U+0000), then throw an
			// `InvalidCharacterError` exception and terminate these steps.
			if (codeUnit === 0x0000) {
				throw new InvalidCharacterError(
					'Invalid character: the input contains U+0000.'
				);
			}

			if (
				// If the character is in the range [\1-\1F] (U+0001 to U+001F) or is
				// U+007F, […]
				(codeUnit >= 0x0001 && codeUnit <= 0x001F) || codeUnit == 0x007F ||
				// If the character is the first character and is in the range [0-9]
				// (U+0030 to U+0039), […]
				(index === 0 && codeUnit >= 0x0030 && codeUnit <= 0x0039) ||
				// If the character is the second character and is in the range [0-9]
				// (U+0030 to U+0039) and the first character is a `-` (U+002D), […]
				(
					index === 1 &&
					codeUnit >= 0x0030 && codeUnit <= 0x0039 &&
					firstCodeUnit === 0x002D
				)
			) {
				// http://dev.w3.org/csswg/cssom/#escape-a-character-as-code-point
				result += '\\' + codeUnit.toString(16) + ' ';
				continue;
			}

			// If the character is not handled by one of the above rules and is
			// greater than or equal to U+0080, is `-` (U+002D) or `_` (U+005F), or
			// is in one of the ranges [0-9] (U+0030 to U+0039), [A-Z] (U+0041 to
			// U+005A), or [a-z] (U+0061 to U+007A), […]
			if (
				codeUnit >= 0x0080 ||
				codeUnit === 0x002D ||
				codeUnit === 0x005F ||
				codeUnit >= 0x0030 && codeUnit <= 0x0039 ||
				codeUnit >= 0x0041 && codeUnit <= 0x005A ||
				codeUnit >= 0x0061 && codeUnit <= 0x007A
			) {
				// the character itself
				result += string.charAt(index);
				continue;
			}

			// Otherwise, the escaped character.
			// http://dev.w3.org/csswg/cssom/#escape-a-character
			result += '\\' + string.charAt(index);

		}

		// Return sanitized hash
		return '#' + result;

	};