shouldBe("function f() { --g(); } f.toString()", "'function f() { --g(); }'");
shouldBe("function f() { g() = 1; } f.toString()", "'function f() { g() = 1; }'");
shouldBe("function f() { g() += 1; } f.toString()", "'function f() { g() += 1; }'");
-shouldThrow("g()++", "'ReferenceError: Postfix ++ operator applied to value that is not a reference.'");
-shouldThrow("g()--", "'ReferenceError: Postfix -- operator applied to value that is not a reference.'");
-shouldThrow("++g()", "'ReferenceError: Prefix ++ operator applied to value that is not a reference.'");
-shouldThrow("--g()", "'ReferenceError: Prefix -- operator applied to value that is not a reference.'");
-shouldThrow("g() = 1", "'ReferenceError: Left side of assignment is not a reference.'");
-shouldThrow("g() += 1", "'ReferenceError: Left side of assignment is not a reference.'");
+shouldThrow("Number()++", "'ReferenceError: Invalid left-hand side expression in postfix operation'");
+shouldThrow("Number()--", "'ReferenceError: Invalid left-hand side expression in postfix operation'");
+shouldThrow("++Number()", "'ReferenceError: Invalid left-hand side expression in prefix operation'");
+shouldThrow("--Number()", "'ReferenceError: Invalid left-hand side expression in prefix operation'");
+shouldThrow("Number() = 1", "'ReferenceError: Invalid left-hand side in assignment'");
+shouldThrow("Number() += 1", "'ReferenceError: Invalid left-hand side in assignment'");