nitc/abscomp: cleanup, document and fix autoadapt (no change)

The fix is do not change the static type on type adaptation!

Signed-off-by: Jean Privat <jean@pryen.org>

diff --git a/src/compiler/abstract_compiler.nit b/src/compiler/abstract_compiler.nit
index 3384473..5fca1a1 100644 (file)
--- a/src/compiler/abstract_compiler.nit
+++ b/src/compiler/abstract_compiler.nit
@@ -1273,17 +1273,21 @@ abstract class AbstractCompilerVisitor
        do
                mtype = self.anchor(mtype)
                var valmtype = value.mcasttype
+
+               # Do nothing if useless autocast
                if valmtype.is_subtype(self.compiler.mainmodule, null, mtype) then
                        return value
                end
 
+               # Just as_not_null if the target is not nullable.
+               #
+               # eg `nullable PreciseType` adapted to `Object` gives precisetype.
                if valmtype isa MNullableType and valmtype.mtype.is_subtype(self.compiler.mainmodule, null, mtype) then
-                       var res = new RuntimeVariable(value.name, valmtype, valmtype.mtype)
-                       return res
-               else
-                       var res = new RuntimeVariable(value.name, valmtype, mtype)
-                       return res
+                       mtype = valmtype.mtype
                end
+
+               var res = new RuntimeVariable(value.name, value.mtype, mtype)
+               return res
        end
 
        # Generate a super call from a method definition