typing: refactor type adaptations in AEqExpr and ANeExpr

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

diff --git a/src/semantize/typing.nit b/src/semantize/typing.nit
index cf84e4c..f254292 100644 (file)
--- a/src/semantize/typing.nit
+++ b/src/semantize/typing.nit
@@ -195,6 +195,36 @@ private class TypeVisitor
                return sup
        end
 
+       # Special verification on != and == for null
+       # Return true
+       fun null_test(anode: ABinopExpr)
+       do
+               var mtype = anode.n_expr.mtype
+               var mtype2 = anode.n_expr2.mtype
+
+               if mtype == null or mtype2 == null then return
+
+               if not mtype2 isa MNullType then return
+
+               if not mtype isa MNullableType then
+                       return
+               end
+
+               # Check for type adaptation
+               var variable = anode.n_expr.its_variable
+               if variable == null then return
+
+               if anode isa AEqExpr then
+                       anode.after_flow_context.when_true.set_var(variable, mtype2)
+                       anode.after_flow_context.when_false.set_var(variable, mtype.mtype)
+               else if anode isa ANeExpr then
+                       anode.after_flow_context.when_false.set_var(variable, mtype2)
+                       anode.after_flow_context.when_true.set_var(variable, mtype.mtype)
+               else
+                       abort
+               end
+       end
+
        fun try_get_mproperty_by_name2(anode: ANode, mtype: MType, name: String): nullable MProperty
        do
                return self.modelbuilder.try_get_mproperty_by_name2(anode, mmodule, mtype, name)
@@ -1336,16 +1366,7 @@ redef class AEqExpr
        redef fun accept_typing(v)
        do
                super
-
-               var variable = self.n_expr.its_variable
-               if variable == null then return
-               var mtype = self.n_expr2.mtype
-               if not mtype isa MNullType then return
-               var vartype = v.get_variable(self, variable)
-               if not vartype isa MNullableType then return
-               self.after_flow_context.when_true.set_var(variable, mtype)
-               self.after_flow_context.when_false.set_var(variable, vartype.mtype)
-               #debug("adapt {variable}:{vartype} ; true->{mtype} false->{vartype.mtype}")
+               v.null_test(self)
        end
 end
 redef class ANeExpr
@@ -1353,16 +1374,7 @@ redef class ANeExpr
        redef fun accept_typing(v)
        do
                super
-
-               var variable = self.n_expr.its_variable
-               if variable == null then return
-               var mtype = self.n_expr2.mtype
-               if not mtype isa MNullType then return
-               var vartype = v.get_variable(self, variable)
-               if not vartype isa MNullableType then return
-               self.after_flow_context.when_false.set_var(variable, mtype)
-               self.after_flow_context.when_true.set_var(variable, vartype.mtype)
-               #debug("adapt {variable}:{vartype} ; true->{vartype.mtype} false->{mtype}")
+               v.null_test(self)
        end
 end
 redef class ALtExpr