tests: Add a test for class singleton properties.

tests/tests/regression_tests.rs

@@ -204,6 +204,7 @@ swf_tests! {
     (as3_class_enumeration, "avm2/class_enumeration", 1),
     (as3_class_is, "avm2/class_is", 1),
     (as3_class_methods, "avm2/class_methods", 1),
+    (as3_class_singleton, "avm2/class_singleton", 1),
     (as3_class_supercalls_mismatched, "avm2/class_supercalls_mismatched", 1),
     (as3_class_to_locale_string, "avm2/class_to_locale_string", 1),
     (as3_class_to_string, "avm2/class_to_string", 1),

tests/tests/swfs/avm2/class_singleton/Test.as

@@ -0,0 +1,32 @@
+package {
+	public class Test {}
+}
+
+class ES4Class {
+	public static var INSTANCE: ES4Class = new ES4Class();
+	
+	public static var NULL: ES4Class = null;
+	
+	public static var UNDEFINED: ES4Class = undefined;
+}
+
+trace("///ES4Class.INSTANCE === null");
+trace(ES4Class.INSTANCE === null);
+trace("///ES4Class.INSTANCE === undefined");
+trace(ES4Class.INSTANCE === undefined);
+trace("///ES4Class.INSTANCE is ES4Class");
+trace(ES4Class.INSTANCE is ES4Class);
+
+trace("///ES4Class.NULL === null");
+trace(ES4Class.NULL === null);
+trace("///ES4Class.NULL === undefined");
+trace(ES4Class.NULL === undefined);
+trace("///ES4Class.NULL is ES4Class");
+trace(ES4Class.NULL is ES4Class);
+
+trace("///ES4Class.UNDEFINED === null");
+trace(ES4Class.UNDEFINED === null);
+trace("///ES4Class.UNDEFINED === undefined");
+trace(ES4Class.UNDEFINED === undefined);
+trace("///ES4Class.UNDEFINED is ES4Class");
+trace(ES4Class.UNDEFINED is ES4Class);

tests/tests/swfs/avm2/class_singleton/output.txt

@@ -0,0 +1,18 @@
+///ES4Class.INSTANCE === null
+false
+///ES4Class.INSTANCE === undefined
+false
+///ES4Class.INSTANCE is ES4Class
+true
+///ES4Class.NULL === null
+true
+///ES4Class.NULL === undefined
+false
+///ES4Class.NULL is ES4Class
+false
+///ES4Class.UNDEFINED === null
+true
+///ES4Class.UNDEFINED === undefined
+false
+///ES4Class.UNDEFINED is ES4Class
+false