API: Allow explicit installation of system packages

master_changes.md

@@ -158,6 +158,8 @@ users)
 # API updates
 ## opam-client
   * `OpamClient.init` and `OpamClient.reinit`: now can have additional cygwin packages to install [#5930 @moyodiallo]
+  * Expose `OpamSolution.print_depext_msg` [#5994 @dra27]
+  * Extracted `OpamSolution.install_sys_packages` from `OpamSolution.install_depexts` [#5994 @dra27]
 
 ## opam-repository
 

src/client/opamSolution.ml

@@ -1146,34 +1146,11 @@ let get_depexts ?(force=false) ?(recover=false) t packages =
   print_depext_msg (avail, nf);
   avail
 
-let install_depexts ?(force_depext=false) ?(confirm=true) t packages =
-  let confirm =
-    confirm && not (OpamSysInteract.Cygwin.is_internal t.switch_global.config)
-  in
-  let sys_packages =
-    get_depexts ~force:force_depext ~recover:force_depext t packages
-  in
-  let env = t.switch_global.global_variables in
-  let config = t.switch_global.config in
-  let map_sysmap f t =
-    let sys_packages =
-      OpamPackage.Set.fold (fun nv sys_map ->
-          match OpamPackage.Map.find_opt nv sys_map with
-          | Some status ->
-            OpamPackage.Map.add
-              nv { status with OpamSysPkg.s_available =
-                                 f status.OpamSysPkg.s_available }
-              sys_map
-          | None -> sys_map)
-        packages
-        (Lazy.force t.sys_packages)
-    in
-    { t with sys_packages = lazy sys_packages }
-  in
+let install_sys_packages ~map_sysmap ~confirm env config sys_packages t =
   let rec entry_point t sys_packages =
     if OpamClientConfig.(!r.fake) then
       (print_command sys_packages; t)
-    else if OpamFile.Config.depext_run_installs t.switch_global.config then
+    else if OpamFile.Config.depext_run_installs config then
       if confirm then menu t sys_packages else auto_install t sys_packages
     else
       manual_install t sys_packages
@@ -1297,6 +1274,35 @@ let install_depexts ?(force_depext=false) ?(confirm=true) t packages =
     entry_point t sys_packages
   with Sys.Break as e -> OpamStd.Exn.finalise e give_up_msg
 
+let install_depexts ?(force_depext=false) ?(confirm=true) t packages =
+  let map_sysmap f t =
+    let sys_packages =
+      OpamPackage.Set.fold (fun nv sys_map ->
+          match OpamPackage.Map.find_opt nv sys_map with
+          | Some status ->
+            OpamPackage.Map.add
+              nv { status with OpamSysPkg.s_available =
+                                 f status.OpamSysPkg.s_available }
+              sys_map
+          | None -> sys_map)
+        packages
+        (Lazy.force t.sys_packages)
+    in
+    { t with sys_packages = lazy sys_packages }
+  in
+  let confirm =
+    confirm && not (OpamSysInteract.Cygwin.is_internal t.switch_global.config)
+  in
+  let sys_packages =
+    get_depexts ~force:force_depext ~recover:force_depext t packages
+  in
+  let env = t.switch_global.global_variables in
+  let config = t.switch_global.config in
+  install_sys_packages ~map_sysmap ~confirm env config sys_packages t
+
+let install_sys_packages ~confirm =
+  install_sys_packages ~map_sysmap:(fun _ () -> ()) ~confirm
+
 (* Apply a solution *)
 let apply ?ask t ~requested ?print_requested ?add_roots
     ?(skip=OpamPackage.Map.empty)

src/client/opamSolution.mli

@@ -75,12 +75,22 @@ val check_solution:
     without actually performing the action(s) on disk. *)
 val dry_run: 'a switch_state -> OpamSolver.solution -> 'a switch_state
 
+(** Given [(available, not_found)] (see {!OpamSysInteract.packages_status}),
+    displays appropriate warnings/messages on the console if either set is
+    non-empty. *)
+val print_depext_msg : OpamSysPkg.Set.t * OpamSysPkg.Set.t -> unit
+
+(** As {!install_depexts}, but supplied with a set of system packages to be
+    installed. *)
+val install_sys_packages: confirm:bool -> OpamStateTypes.gt_variables ->
+  OpamFile.Config.t -> OpamSysPkg.Set.t -> unit -> unit
+
 (* Install external dependencies of the given package set, according the depext
    configuration. If [confirm] is false, install commands are directly
    launched, without asking user (used by the `--depext-only` option). If
    [force_depext] is true, it overrides [OpamFile.Config.depext] value. *)
-val install_depexts:
-  ?force_depext:bool -> ?confirm:bool -> rw switch_state -> package_set -> rw switch_state
+val install_depexts: ?force_depext:bool -> ?confirm:bool -> rw switch_state ->
+  package_set -> rw switch_state
 
 (** {2 Atoms} *)