hashState.js

hashState = function(queries) {
	var k, q;
	if (queries === null) {
		// fx 3.0.x reloads page when hash is empty
		location.hash = '#';
		return null;
	}
	else if (!queries) {
		q = location.hash.slice(1);
		// fx decodes automatically
		if (!$.browser.mozilla) {
			q = decodeURIComponent(q);
		}
		return hashState.parse(q);
	}
	else {
		q = hashState.stringify(queries);
		location.hash = q;
		return q;
	}
};

hashState.stringify = function(queries) {
	var k, v, ret = [];
	for (k in queries) {
		v = queries[k];
		if (typeof v != 'number' && !v || typeof v == 'function') {
			continue;
		}
		if (v === true) {
			ret.push(encodeURIComponent(k));
		}
		else {
			ret.push([encodeURIComponent(k), encodeURIComponent(queries[k])].join('='));
		}
	}
	return ret.join('&');
};

hashState.parse = function(query) {
	var queries = query.split('&'),
		i = 0, q, m, key, value,
		ret = {};
	for (; q = queries[i]; ++i) {
		m = /^([^=]+)=?(.*)$/.exec(q) || [];
		if (m[1]) {
			key = decodeURIComponent(m[1]);
			value = m[2] && decodeURIComponent(m[2]);
			value = value ?
				isNaN(Number(value)) ? value : Number(value) :
				true;
			ret[key] = value;
		}
	}
	return ret;
};

hashState.qunit.js

module('hashState');

test('hashState', 5, function() {
	var params = { foo: 'bar', 'い': 'ろ'},
		ret;
	ret = hashState(params);
	if ($.browser.mozilla) {
		equal(location.hash, '#foo=bar&い=ろ', 'save state to location.hash (Firefox)');
	}
	else {
		equal(location.hash, '#foo=bar&%E3%81%84=%E3%82%8D', 'save state to location.hash');
	}
	equal(ret, 'foo=bar&%E3%81%84=%E3%82%8D', 'return stringify');

	deepEqual(hashState(), params, 'load state from location.hash');

	ret = hashState(null);
	strictEqual(location.hash, '', 'clear location.hash');
	strictEqual(ret, null, 'return null');
});

test('hashState.stringify', 1, function() {
	var params = {
		'string'   : 'a',
		'string0'  : '0',
		'string1'  : '1',
		'number0'  : 0,
		'number1'  : 1,
		'undefined': undefined,
		'null'     : null,
		'true'     : true,
		'false'    : false,
		'function' : function() {},
		'い'        : 'ろ'
	};
	equal(hashState.stringify(params), 'string=a&string0=0&string1=1&number0=0&number1=1&true&%E3%81%84=%E3%82%8D', 'stringify');
});

test('hashState.parse', 1, function() {
	var params = 'string=a&string0=0&string1=1&number0=0&number1=1&true&%E3%81%84=%E3%82%8D';
	deepEqual(hashState.parse(params), {
		'string'   : 'a',
		'string0'  : 0,
		'string1'  : 1,
		'number0'  : 0,
		'number1'  : 1,
		'true'     : true,
		'い'        : 'ろ'
	}, 'parse');
});