Data: camelCasing should not ignore case

Fixes gh-2070

src/core.js

@@ -26,7 +26,7 @@ var
 
 	// Matches dashed string for camelizing
 	rmsPrefix = /^-ms-/,
-	rdashAlpha = /-([a-z])/gi,
+	rdashAlpha = /-([a-z])/g,
 
 	// Used by jQuery.camelCase as callback to replace()
 	fcamelCase = function( all, letter ) {

test/unit/data.js

@@ -592,6 +592,16 @@ test(".data always sets data with the camelCased key (gh-2257)", function() {
 	});
 });
 
+test( ".data should not strip more than one hyphen when camelCasing (gh-2070)", function() {
+	expect( 3 );
+	var div = jQuery( "<div data-nested-single='single' data-nested--double='double' data-nested---triple='triple'></div>" ).appendTo( "#qunit-fixture" ),
+		allData = div.data();
+
+	equal( allData.nestedSingle, "single", "Key is correctly camelCased" );
+	equal( allData[ "nested-Double" ], "double", "Key with double hyphens is correctly camelCased" );
+	equal( allData[ "nested--Triple" ], "triple", "Key with triple hyphens is correctly camelCased" );
+});
+
 test(".data supports interoperable hyphenated/camelCase get/set of properties with arbitrary non-null|NaN|undefined values", function() {
 	var div = jQuery("<div/>", { id: "hyphened" }).appendTo("#qunit-fixture"),
 		datas = {