derive: Implement make_qualified_call helper

This patch implements the make_qualified_call helper function as requested
by the TODO in rust-derive-clone.cc. It refactors DeriveClone::clone_call
to use this new helper, simplifying the construction of qualified paths
for function calls.

Fixes #4393

gcc/rust/ChangeLog:

	* expand/rust-derive-clone.cc (make_qualified_call): New helper function.
	(DeriveClone::clone_call): Use make_qualified_call.

Signed-off-by: Jayant Chauhan <[email protected]>

Author: Pasta-coder

gcc/rust/expand/rust-derive-clone.cc

@@ -27,6 +27,16 @@
 namespace Rust {
 namespace AST {
 
+static std::unique_ptr<Expr>
+make_qualified_call (Builder &builder, std::vector<std::string> segments,
+		     std::vector<std::unique_ptr<Expr>> args)
+{
+  auto path = std::unique_ptr<Expr> (
+    new PathInExpression (builder.path_in_expression (std::move (segments))));
+
+  return builder.call (std::move (path), std::move (args));
+}
+
 std::unique_ptr<Expr>
 DeriveClone::clone_call (std::unique_ptr<Expr> &&to_clone)
 {
@@ -42,13 +52,10 @@ DeriveClone::clone_call (std::unique_ptr<Expr> &&to_clone)
 
   // Not sure how to call it properly in the meantime...
 
-  auto path = std::unique_ptr<Expr> (
-    new PathInExpression (builder.path_in_expression ({"Clone", "clone"})));
-
   auto args = std::vector<std::unique_ptr<Expr>> ();
   args.emplace_back (std::move (to_clone));
 
-  return builder.call (std::move (path), std::move (args));
+  return make_qualified_call (builder, {"Clone", "clone"}, std::move (args));
 }
 
 /**
@@ -104,8 +111,6 @@ DeriveClone::clone_impl (
 			     std::move (generics.impl));
 }
 
-// TODO: Create new `make_qualified_call` helper function
-
 DeriveClone::DeriveClone (location_t loc)
   : DeriveVisitor (loc), expanded (nullptr)
 {}