src: use `as_notnullable` in code

[nit.git] / src / typing.nit

diff --git a/src/typing.nit b/src/typing.nit
index ccd77e2..d2cc5fa 100644 (file)
--- a/src/typing.nit
+++ b/src/typing.nit
@@ -252,7 +252,7 @@ private class TypeVisitor
 
                assert mproperty isa MMethod
 
-               if is_toplevel_context and recv_is_self and not mproperty.is_toplevel and name != "sys" and name != "exit" and name != "args" then
+               if is_toplevel_context and recv_is_self and not mproperty.is_toplevel and name != "sys" and name != "exit" then
                        # FIXME named methods are here as a workaround
                        error(node, "Error: '{name}' is not a top-level method, thus need a receiver.")
                end
@@ -284,7 +284,7 @@ private class TypeVisitor
                var erasure_cast = false
                var rettype = mpropdef.msignature.return_mtype
                if not recv_is_self and rettype != null then
-                       if rettype isa MNullableType then rettype = rettype.mtype
+                       rettype = rettype.as_notnullable
                        if rettype isa MParameterType then
                                var erased_rettype = msignature.return_mtype
                                assert erased_rettype != null
@@ -905,7 +905,7 @@ redef class AForExpr
                # anchor formal and virtual types
                if mtype.need_anchor then mtype = v.anchor_to(mtype)
 
-               if mtype isa MNullableType then mtype = mtype.mtype
+               mtype = mtype.as_notnullable
                self.coltype = mtype.as(MClassType)
 
                # get methods is_ok, next, item
@@ -1008,9 +1008,7 @@ redef class AOrElseExpr
                        return # Skip error
                end
 
-               if t1 isa MNullableType then
-                       t1 = t1.mtype
-               end
+               t1 = t1.as_notnullable
 
                var t = v.merge_types(self, [t1, t2])
                if t == null then
@@ -1194,6 +1192,8 @@ redef class AAsNotnullExpr
        redef fun accept_typing(v)
        do
                var mtype = v.visit_expr(self.n_expr)
+               if mtype == null then return # Forward error
+
                if mtype isa MNullType then
                        v.error(self, "Type error: as(not null) on null")
                        return
@@ -1202,8 +1202,18 @@ redef class AAsNotnullExpr
                        self.mtype = mtype.mtype
                        return
                end
-               # TODO: warn on useless as not null
                self.mtype = mtype
+
+               if mtype isa MClassType then
+                       v.modelbuilder.warning(self, "Warning: expression is already not null, since it is a `{mtype}`.")
+                       return
+               end
+               assert mtype.need_anchor
+               var u = v.anchor_to(mtype)
+               if not u isa MNullableType then
+                       v.modelbuilder.warning(self, "Warning: expression is already not null, since it is a `{mtype}: {u}`.")
+                       return
+               end
        end
 end