Resolve '_opam' links to system switches

admin-scripts/couverture.ml

@@ -102,7 +102,7 @@ let () =
   OpamStateConfig.init ();
   let t =
     OpamState.load_state ~save_cache:false "couverture"
-      OpamStateConfig.(!r.current_switch)
+      (OpamStateConfig.get_switch_opt ())
   in
   let avail = Lazy.force t.OpamState.Types.available_packages in
   let wanted = match Array.to_list Sys.argv with

src/client/opamClient.ml

@@ -408,11 +408,9 @@ let update
   log "UPDATE %a" (slog @@ String.concat ", ") names;
   let rt = OpamRepositoryState.load `Lock_none gt in
   let st, repos_only =
-    if OpamStateConfig.(!r.current_switch) = None then
-      OpamSwitchState.load_virtual gt rt, true
-    else
-      OpamSwitchState.load `Lock_none gt rt (OpamStateConfig.get_switch ()),
-      repos_only
+    match OpamStateConfig.get_switch_opt () with
+    | None -> OpamSwitchState.load_virtual gt rt, true
+    | Some sw -> OpamSwitchState.load `Lock_none gt rt sw, repos_only
   in
   let repo_names =
     let all_repos = OpamRepositoryName.Map.keys rt.repositories in

src/client/opamCommands.ml

@@ -414,7 +414,7 @@ let list ?(force_search=false) () =
       owns_file disjunction search format packages =
     apply_global_options global_options;
     let no_switch =
-      no_switch || OpamStateConfig.(!r.current_switch) = None
+      no_switch || OpamStateConfig.get_switch_opt () = None
     in
     let format =
       let force_all_versions =
@@ -758,7 +758,7 @@ let config =
     match command, params with
     | Some `env, [] ->
       OpamGlobalState.with_ `Lock_none @@ fun gt ->
-      (match OpamStateConfig.(!r.current_switch) with
+      (match OpamStateConfig.get_switch_opt () with
        | None -> `Ok ()
        | Some sw ->
          `Ok (OpamConfigCommand.env gt sw
@@ -1047,7 +1047,7 @@ let env =
     match revert with
     | false ->
       OpamGlobalState.with_ `Lock_none @@ fun gt ->
-      (match OpamStateConfig.(!r.current_switch) with
+      (match OpamStateConfig.get_switch_opt () with
        | None -> ()
        | Some sw ->
          OpamConfigCommand.env gt sw
@@ -1599,7 +1599,7 @@ let repository =
             else if List.mem sw acc then acc
             else acc @ [sw]
           | `Current_switch ->
-            match OpamStateConfig.(!r.current_switch) with
+            match OpamStateConfig.get_switch_opt () with
             | None ->
               OpamConsole.warning "No switch is currently set, maybe you meant \
                                    '--set-default' ?";
@@ -2753,7 +2753,7 @@ let clean =
     in
     let switches =
       if all_switches then OpamGlobalState.switches gt
-      else if switch then match OpamStateConfig.(!r.current_switch) with
+      else if switch then match OpamStateConfig.get_switch_opt () with
         | Some s -> [s]
         | None -> []
       else []

src/client/opamConfigCommand.ml

@@ -301,7 +301,7 @@ let variable gt v =
   | Some c ->
     OpamConsole.msg "%s\n" (OpamVariable.string_of_variable_contents c)
   | None ->
-    match OpamStateConfig.(!r.current_switch) with
+    match OpamStateConfig.get_switch_opt () with
     | None ->
       OpamConsole.error_and_exit `Not_found
         "Variable %s not found"

src/client/opamListCommand.ml

@@ -679,7 +679,7 @@ let display st format packages =
 
 let get_switch_state gt =
   let rt = OpamRepositoryState.load `Lock_none gt in
-  match OpamStateConfig.(!r.current_switch) with
+  match OpamStateConfig.get_switch_opt () with
   | None -> OpamSwitchState.load_virtual gt rt
   | Some sw -> OpamSwitchState.load `Lock_none gt rt sw
 

src/client/opamMain.ml

@@ -45,7 +45,7 @@ let check_and_run_external_commands () =
             ["PATH", PlusEq, OpamFilename.Dir.to_string plugins_bin, None]
           in
           OpamStateConfig.init ~root_dir ();
-          match OpamStateConfig.(!r.current_switch) with
+          match OpamStateConfig.get_switch_opt () with
           | None -> env_array (OpamEnv.get_pure ~updates ())
           | Some sw ->
             env_array
@@ -60,7 +60,7 @@ let check_and_run_external_commands () =
       | None when not has_init -> ()
       | None ->
         (* Look for a corresponding package *)
-        match OpamStateConfig.(!r.current_switch) with
+        match OpamStateConfig.get_switch_opt () with
         | None -> ()
         | Some sw ->
           OpamGlobalState.with_ `Lock_none @@ fun gt ->

src/client/opamSwitchCommand.ml

@@ -70,7 +70,7 @@ let list gt ~print_short =
     List.map (OpamConsole.colorise `blue)
       ["#"; "switch"; "compiler"; "description" ] ::
     List.map (fun (switch, (packages, descr)) ->
-        let current = Some switch = OpamStateConfig.(!r.current_switch) in
+        let current = Some switch = OpamStateConfig.get_switch_opt () in
         List.map
           (if current then OpamConsole.colorise `bold else fun s -> s)
           [ if current then if OpamConsole.utf8 ()
@@ -86,7 +86,7 @@ let list gt ~print_short =
   OpamStd.Format.print_table stdout ~sep:"  "
     (OpamStd.Format.align_table table);
 
-  match OpamStateConfig.(!r.current_switch), OpamStateConfig.(!r.switch_from)
+  match OpamStateConfig.get_switch_opt (), OpamStateConfig.(!r.switch_from)
   with
   | None, _ when OpamFile.Config.installed_switches gt.config <> [] ->
     OpamConsole.note

src/core/opamFilename.ml

@@ -255,6 +255,9 @@ let is_exec file =
 let starts_with dirname filename =
   OpamStd.String.starts_with ~prefix:(Dir.to_string dirname) (to_string filename)
 
+let dir_starts_with pfx dir =
+  OpamStd.String.starts_with ~prefix:(Dir.to_string pfx) (Dir.to_string dir)
+
 let remove_prefix prefix filename =
   let prefix =
     let str = Dir.to_string prefix in

src/core/opamFilename.mli

@@ -207,6 +207,9 @@ val starts_with: Dir.t -> t -> bool
 (** Check whether a filename ends with a given suffix *)
 val ends_with: string -> t -> bool
 
+(** [dir starts_with pfx dir] Check whether [dir] starts with [pfx] *)
+val dir_starts_with: Dir.t -> Dir.t -> bool
+
 (** Check whether a dirname ends with a given suffix *)
 val dir_ends_with: string -> Dir.t -> bool
 

src/format/opamSwitch.ml

@@ -33,5 +33,5 @@ let of_dirname d =
 
 let get_root root s =
   if is_external s
-  then OpamFilename.Op.(OpamFilename.Dir.of_string s / external_dirname)
+  then OpamFilename.Dir.of_string (Filename.concat s external_dirname)
   else OpamFilename.Op.(root / s)

src/state/opamStateConfig.ml

@@ -169,8 +169,22 @@ let load_defaults root_dir =
     update ?current_switch ();
     Some conf
 
-let get_switch () =
+let get_switch_opt () =
   match !r.current_switch with
+  | Some s ->
+    if OpamSwitch.is_external s then
+      let root = !r.root_dir in
+      let switch_root = OpamSwitch.get_root root s in
+      if OpamFilename.dir_starts_with root switch_root then
+        (* actually symlinked to a global switch *)
+        Some (OpamSwitch.of_string
+                (OpamFilename.remove_prefix_dir root switch_root))
+      else Some s
+    else Some s
+  | None -> None
+
+let get_switch () =
+  match get_switch_opt () with
   | Some s -> s
   | None ->
     OpamConsole.error_and_exit `Configuration_error

src/state/opamStateConfig.mli

@@ -64,6 +64,9 @@ val load_defaults: OpamFilename.Dir.t -> OpamFile.Config.t option
 (** Returns the current switch, failing with an error message is none is set. *)
 val get_switch: unit -> switch
 
+(** Returns the current switch, if any is set. *)
+val get_switch_opt: unit -> switch option
+
 (** The function used to locate an external switch from parents of the current
     directory. Takes the opam root as parameter, and rejects any external switch
     configured with a different root *)