Make sure that wrapInner works on elements that have no contents. Fixes #3552.

src/manipulation.js

@@ -77,7 +77,14 @@ jQuery.fn.extend({
 
 	wrapInner: function( html ) {
 		return this.each(function() {
-			jQuery( this ).contents().wrapAll( html );
+			var self = jQuery( this ), contents = self.contents();
+
+			if ( contents.length ) {
+				contents.wrapAll( html );
+
+			} else {
+				self.append( html );
+			}
 		});
 	},
 

test/unit/manipulation.js

@@ -145,7 +145,7 @@ test("wrapAll(String|Element)", function() {
 // })
 
 var testWrapInner = function(val) {
-	expect(6);
+	expect(8);
 	var num = jQuery("#first").children().length;
 	var result = jQuery('#first').wrapInner('<div class="red"><div id="tmp"></div></div>');
 	equals( jQuery("#first").children().length, 1, "Only one child" );
@@ -158,6 +158,11 @@ var testWrapInner = function(val) {
 	equals( jQuery("#first").children().length, 1, "Only one child" );
 	ok( jQuery("#first").children().is("#empty"), "Verify Right Element" );
 	equals( jQuery("#first").children().children().length, num, "Verify Elements Intact" );
+
+	var div = jQuery("<div/>");
+	div.wrapInner("<span></span>");
+	equals(div.children().length, 1, "The contents were wrapped.");
+	equals(div.children()[0].nodeName.toLowerCase(), "span", "A span was inserted.");
 }
 
 test("wrapInner(String|Element)", function() {