Use NullObject convention

dy · dy · commit dab54c4ff1be · 2017-03-04T10:32:22.000-05:00
diff --git a/index.js b/index.js
@@ -11,7 +11,7 @@ module.exports = function rgba (color, normalize) {
 
 	var parsed = parse(color);
 
-	if (!parsed.space) return null;
+	if (!parsed.space) return [];
 
 	if (Array.isArray(color)) return color;
 
diff --git a/test.js b/test.js
@@ -11,5 +11,5 @@ assert.deepEqual(rgba('rgb(300,300,300)'), [1,1,1,1])
 assert.deepEqual(rgba('rgba(-300,-300,-300,-1)'), [0,0,0,0])
 assert.deepEqual(rgba([0,0,0,0]), [0,0,0,0])
 
-assert.equal(rgba('xyz'), null)
+assert.deepEqual(rgba('xyz'), [])
 // console.log(rgba('hsla(170, 50%, 45%, 1)'))
