overloads support return type

#feat

Author: alandefreitas

include/mrdocs/Metadata/Info/Overloads.hpp

@@ -30,6 +30,9 @@ struct OverloadsInfo final
     /// The members of the overload set.
     std::vector<SymbolID> Members;
 
+    /// Info about the return type of this function.
+    Polymorphic<TypeInfo> ReturnType;
+
     //--------------------------------------------
 
     explicit OverloadsInfo(SymbolID const& ID) noexcept

src/lib/Metadata/Info/Overloads.cpp

@@ -51,10 +51,15 @@ addMember(OverloadsInfo& I, FunctionInfo const& Member)
         I.Extraction = Member.Extraction;
         I.Class = Member.Class;
         I.OverloadedOperator = Member.OverloadedOperator;
+        I.ReturnType = Member.ReturnType;
     }
     else
     {
         I.Extraction = leastSpecific(I.Extraction, Member.Extraction);
+        if (I.ReturnType != Member.ReturnType)
+        {
+            I.ReturnType = {};
+        }
     }
     merge(dynamic_cast<SourceInfo&>(I), dynamic_cast<SourceInfo const&>(Member));
     I.Members.push_back(Member.id);