+
+ # Check the visibility of `mtype` as an element of the signature of `mpropdef`.
+ fun check_visibility(node: ANode, mtype: MType, mpropdef: MPropDef)
+ do
+ var mmodule = mpropdef.mclassdef.mmodule
+ var mproperty = mpropdef.mproperty
+
+ # Extract visibility information of the main part of `mtype`
+ # It is a case-by case
+ var vis_type: nullable MVisibility = null # The own visibility of the type
+ var mmodule_type: nullable MModule = null # The origial module of the type
+ mtype = mtype.as_notnullable
+ if mtype isa MClassType then
+ vis_type = mtype.mclass.visibility
+ mmodule_type = mtype.mclass.intro.mmodule
+ else if mtype isa MVirtualType then
+ vis_type = mtype.mproperty.visibility
+ mmodule_type = mtype.mproperty.intro_mclassdef.mmodule
+ else if mtype isa MParameterType then
+ # nothing, always visible
+ else
+ node.debug "Unexpected type {mtype}"
+ abort
+ end
+
+ if vis_type != null then
+ assert mmodule_type != null
+ var vis_module_type = mmodule.visibility_for(mmodule_type) # the visibility of the original module
+ if mproperty.visibility > vis_type then
+ error(node, "Error: The {mproperty.visibility} property `{mproperty}` cannot contain the {vis_type} type `{mtype}`")
+ return
+ else if mproperty.visibility > vis_module_type then
+ error(node, "Error: The {mproperty.visibility} property `{mproperty}` cannot contain the type `{mtype}` from the {vis_module_type} module `{mmodule_type}`")
+ return
+ end
+ end
+
+ # No error, try to go deeper in generic types
+ if node isa AType then
+ for a in node.n_types do
+ var t = a.mtype
+ if t == null then continue # Error, thus skipped
+ check_visibility(a, t, mpropdef)
+ end
+ else if mtype isa MGenericType then
+ for t in mtype.arguments do check_visibility(node, t, mpropdef)
+ end
+ end