Add opam repo show <reponame> support

src/client/opamCommands.ml

@@ -2276,6 +2276,8 @@ let repository cli =
      where they are active.";
     cli_original, "priority", `priority, ["NAME"; "RANK"],
     "Synonym to $(b,add NAME --rank RANK)";
+    cli_original, "show", `show_repo, [],
+    "Show the URL and priority of a repository";
   ] in
   let man = [
     `S Manpage.s_description;
@@ -2580,6 +2582,20 @@ let repository cli =
            '--all' to see all configured repositories.";
       OpamRepositoryCommand.list rt ~global ~switches ~short;
       `Ok ()
+    | Some `show_repo, [ repo_name ] ->
+      OpamRepositoryState.with_ `Lock_none gt @@ fun rt ->
+      let switches =
+        if scope = [] ||
+           List.exists (function
+               | `This_switch | `Current_switch | `Switch _ -> true
+               | _ -> false)
+             scope
+        then switches
+        else all_switches
+      in
+      OpamRepositoryCommand.show_repo rt ~switches
+        (OpamRepositoryName.of_string repo_name);
+      `Ok ()
     | command, params -> bad_subcommand ~cli commands ("repository", command, params)
   in
   mk_command_ret  ~cli cli_original "repository" ~doc ~man

src/client/opamRepositoryCommand.ml

@@ -219,6 +219,34 @@ let list_all rt ~short =
   OpamStd.Format.align_table |>
   OpamConsole.print_table stdout ~sep:" "
 
+let show_repo rt ~switches repo_name =
+  let repos =
+    List.filter_map (fun sw ->
+        let repos =
+          switch_repos rt sw |>
+          List.mapi (fun i repo -> (i+1, repo)) |>
+          List.filter (fun (_, repo) -> OpamRepositoryName.equal repo repo_name)
+        in
+        match repos with
+        | [] -> None
+        | repos -> Some (sw, repos)
+      ) switches
+  in
+  List.iter (fun (sw, repos)  ->
+    List.iter (fun (rank, repo) ->
+          try
+            let r = OpamRepositoryName.Map.find repo rt.repositories in
+            let url =
+              OpamConsole.colorise `underline (OpamUrl.to_string r.repo_url)
+            in
+            OpamConsole.msg "switch: %s\n" (OpamSwitch.to_string sw);
+            OpamConsole.msg "url: %s\n" url;
+            OpamConsole.msg "rank: %d\n" rank;
+          with Not_found ->
+            OpamConsole.msg "%s" (OpamConsole.colorise `red "not found"))
+      repos)
+    repos
+
 let update_with_auto_upgrade rt repo_names =
   let repos = List.map (OpamRepositoryState.get_repo rt) repo_names in
   let failed, rt = OpamUpdate.repositories rt repos in

src/client/opamRepositoryCommand.mli

@@ -27,6 +27,9 @@ val list:
     are selected in. *)
 val list_all: 'a repos_state -> short:bool -> unit
 
+(** Show the URL and priority (rank) of the given repository *)
+val show_repo: 'a repos_state -> switches:switch list -> repository_name -> unit
+
 (** Add a new repository to ~/.opam/repos, without updating any selections *)
 val add:
   rw repos_state -> repository_name -> url -> trust_anchors option ->