PR# 19412 [er] Full class checking and VUAR-2

When compiling the code below in full_class_checking mode, we get a VUAR-2 error:

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
VUAR(2)	Non-compatible actual argument in feature call.	

Type error: non-compatible actual argument in feature call. 
What to do: make sure that type of actual argument is compatible with
  the type of corresponding formal argument. 

Class: Y
Source class: X
Feature: f
Called feature: put (i: INTEGER_32; a: A) from X
Argument name: a
Argument position: 2
Formal argument type: A
Actual argument type: B
Line: 12
        i := Current [b]
->      Current [b] := 1
      end				
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

I think that this is wrong. The code of feature `f' should first be unfolded in the context of class X, and then checked in the context of Y. So the code which should be checked in the context of Y should be:

   Current.put (1, b.to_a)	

And this code is valid.

Interestingly, the compiler does not complain about the previous line:

   i := Current [b]

which uses a similar pattern with `b' which needs to be converted to `b.to_a' in the context of X before being checked in the context of Y.

--
Eric Bezault

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
class TEST

create

	make

feature

	make
		local
			y: Y
		do
			create y
			y.f
		end

end
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
class A

end
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
class B

convert

	to_a: {A}

feature

	to_a: A
		do
			create Result
		end

end
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
class X

feature

	f
		local
			b: B
			i: INTEGER
		do
			create b
			i := Current [b]
			Current [b] := 1
		end

	item alias "[]" (a: A): INTEGER assign put
		do
		end

	put (i: INTEGER; a: A)
		do
		end

end
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
class Y

inherit

	X

end
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~