A little more self-hosting: meta::object_declaration to Cpp2

And fix a bug this exposed - generated `operator=` memberwise emitted wrong syntax for a base type... previous test cases did not have copyable base types, but `cpp2::meta` embraces copyable base types as a design choice which is find because they aren't polymorphic in the usual inheritance sense

Author: hsutter

regression-tests/test-results/version

@@ -1,5 +1,5 @@
 
-cppfront compiler v0.2.1   Build 8507:0751
+cppfront compiler v0.2.1   Build 8507:1428
 Copyright(c) Herb Sutter   All rights reserved
 
 SPDX-License-Identifier: CC-BY-NC-ND-4.0

source/cppfront.cpp

@@ -4497,17 +4497,24 @@ class cppfront
 
                 //  Otherwise, use a default... for a non-copy/move that's the member initializer
                 //  (for which we don't need to emit anything special because it will get used),
-                //  and for a copy/move function we default to "= that.same_member"
+                //  and for a copy/move function we default to "= that.same_member" (or, if this
+                //  is a base type, just "= that")
                 if (!found_explicit_init)
                 {
                     if (emitting_move_that_function)
                     {
-                        initializer = "std::move(that)." + object_name;
+                        initializer = "std::move(that)";
+                        if (!(*object)->has_name("this")) {
+                            initializer += "." + object_name;
+                        }
                         found_default_init = true;
                     }
                     else if (emitting_that_function)
                     {
-                        initializer = "that." + object_name;
+                        initializer = "that";
+                        if (!(*object)->has_name("this")) {
+                            initializer += "." + object_name;
+                        }
                         found_default_init = true;
                     }
                     else if ((*object)->initializer)