Use the logic in pkg_enabled to detect package management

Re-use the function in pkg_enabled, and move it to pkg_common to avoid
repitition. There is already a similar function `check_pkg_management_enabled`
in pkg_common, but we're not using it here because its purpose is to just see if
dune-workspace has (pkg enabled), and it doesn't cover all the cases we want to
check, to know whether package management is enabled.

Signed-off-by: Sudha Parimala <sudharg247@gmail.com>

Author: Sudha247

bin/install_uninstall.ml

@@ -517,21 +517,21 @@ let run
          User_error.raise
            [ Pp.textf "Context %S not found!" (Dune_engine.Context_name.to_string name) ])
   in
-  (match
-     List.find contexts ~f:(fun ctx ->
-       match Context.kind ctx with
-       | Context.Kind.Lock _ -> true
-       | _ -> false)
-   with
-   | Some _ ->
-     User_error.raise
-       [ Pp.text "dune install is not supported with Dune package management." ]
-       ~hints:
-         [ Pp.concat
-             ~sep:Pp.space
-             [ Pp.text "Use"; User_message.command "opam"; Pp.text "instead." ]
-         ]
-   | None -> ());
+  let* source_workspace = Memo.run (Source.Workspace.workspace ()) in
+  let lock_dir_paths =
+    Pkg.Pkg_common.Lock_dirs_arg.lock_dirs_of_workspace
+      Pkg.Pkg_common.Lock_dirs_arg.all
+      source_workspace
+  in
+  if Pkg.Pkg_common.pkg_enabled ~workspace:source_workspace ~lock_dir_paths
+  then
+    User_error.raise
+      [ Pp.text "dune install is not supported with Dune package management." ]
+      ~hints:
+        [ Pp.concat
+            ~sep:Pp.space
+            [ Pp.text "Use"; User_message.command "opam"; Pp.text "instead." ]
+        ];
   let* pkgs =
     match pkgs with
     | _ :: _ -> Fiber.return pkgs

bin/pkg/pkg_common.ml

@@ -207,6 +207,18 @@ module Lock_dirs_arg = struct
   ;;
 end
 
+let pkg_enabled ~(workspace : Workspace.t) ~lock_dir_paths =
+  (* CR-Leonidas-from-XIV: change this logic when we stop detecting lock
+       directories in the source tree *)
+  let any_lockdir_exists =
+    List.exists lock_dir_paths ~f:(fun p -> Fpath.exists (Path.Source.to_string p))
+  in
+  match workspace.config.pkg_enabled with
+  | Set (_, `Enabled) -> true
+  | Set (_, `Disabled) -> false
+  | Unset -> any_lockdir_exists
+;;
+
 let check_pkg_management_enabled () =
   Memo.run
   @@

bin/pkg/pkg_common.mli

@@ -84,4 +84,9 @@ val pp_packages : Dune_pkg.Lock_dir.Pkg.t list -> User_message.Style.t Pp.t
 
 (** [check_pkg_management_enabled ()] checks if package management is enabled in the
     workspace configuration. Raises a user error if it is explicitly disabled. *)
+val pkg_enabled
+  :  workspace:Workspace.t
+  -> lock_dir_paths:Path.Source.t list
+  -> bool
+
 val check_pkg_management_enabled : unit -> unit Fiber.t

bin/pkg/pkg_enabled.ml

@@ -14,17 +14,7 @@ let term =
         Pkg_common.Lock_dirs_arg.all
         workspace
     in
-    let any_lockdir_exists =
-      List.exists lock_dir_paths ~f:(fun p -> Fpath.exists (Path.Source.to_string p))
-    in
-    (* CR-Leonidas-from-XIV: change this logic when we stop detecting lock
-       directories in the source tree *)
-    let enabled =
-      match workspace.config.pkg_enabled with
-      | Set (_, `Enabled) -> true
-      | Set (_, `Disabled) -> false
-      | Unset -> any_lockdir_exists
-    in
+    let enabled = Pkg_common.pkg_enabled ~workspace ~lock_dir_paths in
     match enabled with
     | true -> ()
     | false -> exit 1)