fix(jqLite): attr for boolean attribute should lowercase value

src/jqLite.js

@@ -290,7 +290,7 @@ var JQLitePrototype = JQLite.prototype = {
 // value on get.
 //////////////////////////////////////////
 var BOOLEAN_ATTR = {};
-forEach('multiple,selected,checked,disabled,readOnly,required'.split(','), function(value, key) {
+forEach('multiple,selected,checked,disabled,readOnly,required'.split(','), function(value) {
   BOOLEAN_ATTR[lowercase(value)] = value;
 });
 
@@ -340,17 +340,22 @@ forEach({
   },
 
   attr: function(element, name, value){
-    if (BOOLEAN_ATTR[name]) {
+    var lowercasedName = lowercase(name);
+    if (BOOLEAN_ATTR[lowercasedName]) {
       if (isDefined(value)) {
         if (!!value) {
           element[name] = true;
-          element.setAttribute(name, name);
+          element.setAttribute(name, lowercasedName);
         } else {
           element[name] = false;
-          element.removeAttribute(name);
+          element.removeAttribute(lowercasedName);
         }
       } else {
-        return (element[name] || element.getAttribute(name)) ? name : undefined;
+        return (element[name] ||
+                 element.getAttribute(name) !== null &&
+                 (msie < 9 ? element.getAttribute(name) !== '' : true))
+               ? lowercasedName
+               : undefined;
       }
     } else if (isDefined(value)) {
       element.setAttribute(name, value);

test/jqLiteSpec.js

@@ -15,7 +15,7 @@ describe('jqLite', function() {
     this.addMatchers({
       toJqEqual: function(expected) {
         var msg = "Unequal length";
-        this.message = function() { return msg; };
+        this.message = function() {return msg;};
 
         var value = this.actual && expected && this.actual.length == expected.length;
         for (var i = 0; value && i < expected.length; i++) {
@@ -191,13 +191,16 @@ describe('jqLite', function() {
       expect(jqLite(b).attr('prop')).toBeFalsy();
     });
 
-    it('should read special attributes as strings', function() {
+    it('should read boolean attributes as strings', function() {
       var select = jqLite('<select>');
       expect(select.attr('multiple')).toBeUndefined();
       expect(jqLite('<select multiple>').attr('multiple')).toBe('multiple');
       expect(jqLite('<select multiple="">').attr('multiple')).toBe('multiple');
       expect(jqLite('<select multiple="x">').attr('multiple')).toBe('multiple');
+    });
 
+    it('should add/remove boolean attributes', function() {
+      var select = jqLite('<select>');
       select.attr('multiple', false);
       expect(select.attr('multiple')).toBeUndefined();
 
@@ -205,6 +208,29 @@ describe('jqLite', function() {
       expect(select.attr('multiple')).toBe('multiple');
     });
 
+    it('should normalize the case of boolean attributes', function() {
+      var input = jqLite('<input readonly>');
+      expect(input.attr('readonly')).toBe('readonly');
+      expect(input.attr('readOnly')).toBe('readonly');
+      expect(input.attr('READONLY')).toBe('readonly');
+
+      input.attr('readonly', false);
+
+      // attr('readonly') fails in jQuery 1.6.4, so we have to bypass it
+      //expect(input.attr('readOnly')).toBeUndefined();
+      //expect(input.attr('readonly')).toBeUndefined();
+      if (msie < 9) {
+        expect(input[0].getAttribute('readonly')).toBe('');
+      } else {
+        expect(input[0].getAttribute('readonly')).toBe(null);
+      }
+      //expect('readOnly' in input[0].attributes).toBe(false);
+
+      input.attr('readOnly', 'READonly');
+      expect(input.attr('readonly')).toBe('readonly');
+      expect(input.attr('readOnly')).toBe('readonly');
+    });
+
     it('should return undefined for non-existing attributes', function() {
       var elm = jqLite('<div class="any">a</div>');
       expect(elm.attr('non-existing')).toBeUndefined();