fix data-* attributes not being set properly

fixes choojs#28

index.js

@@ -59,7 +59,8 @@ module.exports = function (h, opts) {
             if (typeof parts[i][2] === 'object' && !key) {
               for (copyKey in parts[i][2]) {
                 if (parts[i][2].hasOwnProperty(copyKey) && !cur[1][copyKey]) {
-                  cur[1][copyKey] = parts[i][2][copyKey]
+                  if (/data-/.test(copyKey)) data(cur[1], copyKey, parts[i][2][copyKey])
+                  else cur[1][copyKey] = parts[i][2][copyKey]
                 }
               }
             } else {
@@ -71,11 +72,13 @@ module.exports = function (h, opts) {
         var j = i
         for (; i < parts.length; i++) {
           if (parts[i][0] === ATTR_VALUE || parts[i][0] === ATTR_KEY) {
-            if (!cur[1][key]) cur[1][key] = strfn(parts[i][1])
+            if (/data-/.test(key)) data(cur[1], key, parts[i][1])
+            else if (!cur[1][key]) cur[1][key] = strfn(parts[i][1])
             else cur[1][key] = concat(cur[1][key], parts[i][1])
           } else if (parts[i][0] === VAR
           && (parts[i][1] === ATTR_VALUE || parts[i][1] === ATTR_KEY)) {
-            if (!cur[1][key]) cur[1][key] = strfn(parts[i][2])
+            if (/data-/.test(key)) data(cur[1], key, parts[i][2])
+            else if (!cur[1][key]) cur[1][key] = strfn(parts[i][2])
             else cur[1][key] = concat(cur[1][key], parts[i][2])
           } else {
             if (key.length && !cur[1][key] && i === j
@@ -229,6 +232,11 @@ module.exports = function (h, opts) {
     }
   }
 
+  function data(cur, key, value) {
+    if (!cur.attributes) cur.attributes = {}
+    cur.attributes[key] = strfn(value)
+  }
+
   function strfn (x) {
     if (typeof x === 'function') return x
     else if (typeof x === 'string') return x

test/key.js

@@ -50,8 +50,8 @@ test('multiple keys', function (t) {
   }
   var key = 'data-'
   var value = 'bar'
-  var tree = hx`<input ${props} ${key}foo=${value}>`
-  t.equal(vdom.create(tree).toString(), '<input type="text" data-special="true" data-foo="bar" />')
+  var tree = hx`<input ${props} ${key}foo=${value} data-bar="baz">`
+  t.equal(vdom.create(tree).toString(), '<input type="text" data-special="true" data-foo="bar" data-bar="baz" />')
   t.end()
 })