Assignable fixes for reference member variables

Fix incorrect variable setters being generated when wrapping
reference member variables. A setter is no longer generated if the
type of the reference member variable is non-assignable.

Fixes #2866

CHANGES.current

@@ -7,6 +7,11 @@ the issue number to the end of the URL: https://github.com/swig/swig/issues/
 Version 4.3.0 (in progress)
 ===========================
 
+2024-09-19: wsfulton
+            #2866 Fix incorrect variable setters being generated when wrapping
+            reference member variables. A setter is no longer generated if the
+            type of the reference member variable is non-assignable.
+
 2024-09-18: olly
 	    Fix parse error for a misplaced Doxygen comment which is the only
 	    thing in a class/struct.

Examples/test-suite/cpp11_assign_delete.i

@@ -170,3 +170,53 @@ struct StaticMembersMemberArrayVarsHolder {
 };
 StaticMembersMemberArrayVars GlobalStaticMembersMemberArrayVars;
 %}
+
+// (5) Test indirectly non-assignable member variables via classes that themselves have non-assignable reference member variables
+%inline %{
+AssignPublic GlobalAssignPublic;
+AssignProtected GlobalAssignProtected;
+AssignPrivate GlobalAssignPrivate;
+
+struct MemberPublicRefVar {
+  AssignPublic& MemberRefVarPublic;
+  MemberPublicRefVar() : MemberRefVarPublic(GlobalAssignPublic) {}
+};
+
+struct MemberProtectedRefVar {
+  MemberProtectedRefVar() : MemberRefVarProtected(GlobalAssignProtected) {}
+protected:
+  AssignProtected& MemberRefVarProtected;
+};
+
+struct MemberPrivateRefVar {
+  MemberPrivateRefVar() : MemberRefVarPrivate(GlobalAssignPrivate) {}
+private:
+  AssignPrivate& MemberRefVarPrivate;
+};
+
+struct MembersMemberRefVars {
+  // These will only have getters
+  MemberPublicRefVar MemberPublic;
+  MemberProtectedRefVar MemberProtected;
+  MemberPrivateRefVar MemberPrivate;
+};
+
+struct StaticMembersMemberRefVars {
+  static MemberPublicRefVar StaticMemberPublic;
+  static MemberProtectedRefVar StaticMemberProtected;
+  static MemberPrivateRefVar StaticMemberPrivate;
+};
+MemberPublicRefVar StaticMembersMemberRefVars::StaticMemberPublic;
+MemberProtectedRefVar StaticMembersMemberRefVars::StaticMemberProtected;
+MemberPrivateRefVar StaticMembersMemberRefVars::StaticMemberPrivate;
+
+MemberPublicRefVar GlobalRefMemberPublic;
+MemberProtectedRefVar GlobalRefMemberProtected;
+MemberPrivateRefVar GlobalRefMemberPrivate;
+
+// Setters and getters available
+struct StaticMembersMemberRefVarsHolder {
+    StaticMembersMemberRefVars Member;
+};
+StaticMembersMemberRefVars GlobalStaticMembersMemberRefVars;
+%}

Examples/test-suite/java/cpp11_assign_delete_runme.java

@@ -114,5 +114,31 @@ public class cpp11_assign_delete_runme {
     StaticMembersMemberArrayVars smmv = cpp11_assign_delete.getGlobalStaticMembersMemberArrayVars();
     cpp11_assign_delete.setGlobalStaticMembersMemberArrayVars(smmv);
     }
+
+    // (5) Test indirectly non-assignable member variables via classes that themselves have non-assignable reference member variables
+    {
+    MembersMemberRefVars m = new MembersMemberRefVars();
+
+    // These will only have getters
+    MemberPublicRefVar mpv1 = m.getMemberPublic();
+    MemberProtectedRefVar mpv2 = m.getMemberProtected();
+    MemberPrivateRefVar mpv3 = m.getMemberPrivate();
+
+    MemberPublicRefVar smpv1 = StaticMembersMemberRefVars.getStaticMemberPublic();
+    MemberProtectedRefVar smpv2 = StaticMembersMemberRefVars.getStaticMemberProtected();
+    MemberPrivateRefVar smpv3 = StaticMembersMemberRefVars.getStaticMemberPrivate();
+
+    MemberPublicRefVar gmpv1 = cpp11_assign_delete.getGlobalRefMemberPublic();
+    MemberProtectedRefVar gmpv2 = cpp11_assign_delete.getGlobalRefMemberProtected();
+    MemberPrivateRefVar gmpv3 = cpp11_assign_delete.getGlobalRefMemberPrivate();
+
+    // Setters and getters available
+    StaticMembersMemberRefVarsHolder smmvh = new StaticMembersMemberRefVarsHolder();
+    StaticMembersMemberRefVars member = smmvh.getMember();
+    smmvh.setMember(member);
+
+    StaticMembersMemberRefVars smmv = cpp11_assign_delete.getGlobalStaticMembersMemberRefVars();
+    cpp11_assign_delete.setGlobalStaticMembersMemberRefVars(smmv);
+    }
   }
 }

Source/Modules/allocate.cxx

@@ -692,6 +692,11 @@ class Allocate:public Dispatcher {
     } else if (SwigType_isarray(type)) {
       SwigType *array_type = SwigType_array_type(type);
       assignable = is_assignable_type(array_type);
+    } else if (SwigType_isreference(type) || SwigType_isrvalue_reference(type)) {
+      SwigType *base_type = Copy(type);
+      SwigType_del_element(base_type);
+      assignable = is_assignable_type(base_type);
+      Delete(base_type);
     }
     return assignable;
   }