diff --git a/compiler/testData/diagnostics/tests/override/ExtendFunctionClass.jet b/compiler/testData/diagnostics/tests/override/ExtendFunctionClass.jet
index 6566a78c306..c0b0380a00a 100644
--- a/compiler/testData/diagnostics/tests/override/ExtendFunctionClass.jet
+++ b/compiler/testData/diagnostics/tests/override/ExtendFunctionClass.jet
@@ -1,6 +1,6 @@
 package extendFunctionClass
 
-class <!ABSTRACT_MEMBER_NOT_IMPLEMENTED!>A<!> : (Int) -> Int {
+class <!ABSTRACT_MEMBER_NOT_IMPLEMENTED!>A<!> : Function1<Int, Int>() {
 
 }