Remove dead code in Modules (#12635)

* refactor: remove unused function [Modules.With_vlib.main_module_name]

Signed-off-by: Rudi Grinberg <[email protected]>

Author: rgrinberg

src/dune_rules/modules.ml

@@ -1029,19 +1029,6 @@ module With_vlib = struct
     | Impl { impl = _; vlib; _ } -> lib_interface vlib
   ;;
 
-  let main_module_name =
-    let main_module_name t =
-      match t.modules with
-      | Singleton m -> Some (Module.name m)
-      | Unwrapped _ -> None
-      | Wrapped w -> Some w.group.name
-      | Stdlib w -> Some w.main_module_name
-    in
-    function
-    | Modules t -> main_module_name t
-    | Impl { vlib; impl = _; _ } -> main_module_name vlib
-  ;;
-
   let impl =
     let empty = lazy Module_name.Unique.Map.empty in
     fun impl ~vlib ->

src/dune_rules/modules.mli

@@ -101,10 +101,6 @@ module With_vlib : sig
   (** Returns all the compatibility modules. *)
   val wrapped_compat : t -> Module.Name_map.t
 
-  (** Returns the main module name if it exists. It exist for libraries with
-      [(wrapped true)] or one module libraries. *)
-  val main_module_name : t -> Module_name.t option
-
   val version_installed : t -> src_root:Path.t -> install_dir:Path.t -> t
   val alias_for : t -> Module.t -> Module.t list
   val local_open : t -> Module.t -> Module_name.t list