make sure testset in function will still trigger error

Author: MilesCranmer

test/loading.jl

@@ -131,23 +131,27 @@ end
             test_do_block()
         end
 
+        @testset "Error upon misuse" begin
+            @gensym A
+            @test_throws(
+                "@__FUNCTION__ can only be used within a function",
+                @eval(module $A; @__FUNCTION__; end)
+            )
+        end
+
         @testset "Callable structs throw error" begin
+            @gensym A
+            @eval module $A
             struct CallableStruct{T}
                 val::T
             end
             function (c::CallableStruct)()
                 return @__FUNCTION__
             end
+            end
+            @eval using .$A: CallableStruct
             c = CallableStruct(5)
-            @test_throws UndefVarError c()
-        end
-
-        @testset "Error upon misuse" begin
-            @gensym A
-            @test_throws(
-                "@__FUNCTION__ can only be used within a function",
-                @eval(module $A; @__FUNCTION__; end)
-            )
+            @test_throws "@__FUNCTION__ can only be used within a function" c()
         end
     end
 end