Calling load with null as the data parameter now properly issues a GET...

Calling load with null as the data parameter now properly issues a GET request, not a POST request. Unit tests added. Fixes #12234.

src/ajax.js

@@ -170,7 +170,7 @@ jQuery.fn.load = function( url, params, callback ) {
 		params = undefined;
 
 	// Otherwise, build a param string
-	} else if ( typeof params === "object" ) {
+	} else if ( params && typeof params === "object" ) {
 		type = "POST";
 	}
 

test/unit/ajax.js

@@ -1037,11 +1037,45 @@ test("global ajaxSettings", function() {
 */
 
 test("load(String)", function() {
-	expect(1);
+	expect(2);
 	stop(); // check if load can be called with only url
+	jQuery.ajaxSetup({
+		beforeSend: function() {
+			strictEqual( this.type, "GET", "no data means GET request" );
+		}
+	});
 	jQuery("#first").load("data/name.html", function() {
 		start();
 	});
+	jQuery.ajaxSetup({
+		beforeSend: null
+	});
+});
+
+test("load(String,null)", function() {
+	expect(2);
+	stop(); // check if load can be called with url and null data
+	jQuery.ajaxSetup({
+		beforeSend: function() {
+			strictEqual( this.type, "GET", "no data means GET request" );
+		}
+	});
+	jQuery("#first").load("data/name.html", null, function() {
+		start();
+	});
+});
+
+test("load(String,undefined)", function() {
+	expect(2);
+	stop(); // check if load can be called with url and null data
+	jQuery.ajaxSetup({
+		beforeSend: function() {
+			strictEqual( this.type, "GET", "no data means GET request" );
+		}
+	});
+	jQuery("#first").load("data/name.html", undefined, function() {
+		start();
+	});
 });
 
 test("load('url selector')", function() {