lint and a few issues that seem quite serious

.jshintrc

@@ -0,0 +1,23 @@
+{
+  "asi": true,
+  "curly": false,
+  "eqeqeq": false,
+  "eqnull": true,
+  "immed": true,
+  "latedef": "nofunc",
+  "laxbreak": true,
+  "mocha" : true,
+  "newcap": true,
+  "noarg": true,
+  "browser": true,
+  "shadow": true,
+  "sub": true,
+  "undef": true,
+  "unused": true,
+  "globals": {
+    "exports": false,
+    "require": false,
+    "module": false
+  }
+
+}

Makefile

@@ -11,4 +11,7 @@ clean:
 test:
 	@./node_modules/.bin/component-test phantom
 
+lint:
+	@./node_modules/.bin/jshint index.js lib test
+
 .PHONY: clean test

lib/css.js

@@ -76,5 +76,5 @@ function css(el, prop, extra, styles) {
  */
 
 function isNumeric(obj) {
-  return !isNan(parseFloat(obj)) && isFinite(obj);
+  return !isNaN(parseFloat(obj)) && isFinite(obj);
 }

lib/hooks.js

@@ -32,9 +32,9 @@ each(['width', 'height'], function(name) {
   }
 
   exports[name].set = function(el, val, extra) {
-    var styles = extra && styles(el);
+    var elStyles = extra && styles(el);
     return setPositiveNumber(el, val, extra
-      ? augmentWidthOrHeight(el, name, extra, 'border-box' == css(el, 'boxSizing', false, styles), styles)
+      ? augmentWidthOrHeight(el, name, extra, 'border-box' == css(el, 'boxSizing', false, elStyles), elStyles)
       : 0
     );
   };

lib/prop.js

@@ -3,7 +3,6 @@
  */
 
 var debug = require('debug')('css:prop');
-var camelcase = require('to-camel-case');
 var vendor = require('./vendor');
 
 /**

lib/swap.js

@@ -15,6 +15,8 @@ module.exports = swap;
  */
 
 function swap(el, options, fn, args) {
+  var old = {}, ret;
+
   // Remember the old values, and insert the new ones
   for (var key in options) {
     old[key] = el.style[key];

package.json

@@ -10,9 +10,10 @@
     "component-each": "~0.2.2"
   },
   "devDependencies": {
+    "component-test2": "*",
     "domify": "^1.2.2",
-    "load-styles": "^1.0.1",
-    "component-test2": "*"
+    "jshint": "^2.7.0",
+    "load-styles": "^1.0.1"
   },
   "browser": {
     "each": "component-each"