Fix Placeholders.disable/enable methods when applied to all affected …

…elements. Closes jamesallardice#23

lib/main.js

@@ -79,10 +79,11 @@
 
     // Show the placeholder value on a single element. Returns true if the placeholder was shown and false if it was not (because it was already visible)
     function showPlaceholder(elem) {
-        var type;
-        if (elem.value === "") {
+        var type,
+            val = elem.getAttribute(ATTR_CURRENT_VAL);
+        if (elem.value === "" && val) {
             elem.setAttribute(ATTR_ACTIVE, "true");
-            elem.value = elem.getAttribute(ATTR_CURRENT_VAL);
+            elem.value = val;
             elem.className += " " + placeholderClassName;
 
             // If the type of element needs to change, change it (e.g. password inputs)
@@ -101,20 +102,20 @@
 
     function handleElem(node, callback) {
 
-        var inputs, textareas, elem, len, i;
+        var handleInputs, handleTextareas, elem, len, i;
 
         // Check if the passed in node is an input/textarea (in which case it can't have any affected descendants)
         if (node && node.getAttribute(ATTR_CURRENT_VAL)) {
             callback(node);
         } else {
 
             // If an element was passed in, get all affected descendants. Otherwise, get all affected elements in document
-            inputs = node ? node.getElementsByTagName("input") : inputs;
-            textareas = node ? node.getElementsByTagName("textarea") : textareas;
+            handleInputs = node ? node.getElementsByTagName("input") : inputs;
+            handleTextareas = node ? node.getElementsByTagName("textarea") : textareas;
 
             // Run the callback for each element
-            for (i = 0, len = inputs.length + textareas.length; i < len; i++) {
-                elem = i < inputs.length ? inputs[i] : textareas[i - inputs.length];
+            for (i = 0, len = handleInputs.length + handleTextareas.length; i < len; i++) {
+                elem = i < handleInputs.length ? handleInputs[i] : handleTextareas[i - handleInputs.length];
                 callback(elem);
             }
         }