Define a User type

bin/main.ml

@@ -68,9 +68,18 @@ let period =
   in
   Term.(const f $ from $ to_ $ last_week)
 
-let user =
+let user : User.t Term.t =
+  let str_parser, str_printer = Arg.string in
+  let parser x =
+    match str_parser x with `Ok x -> `Ok (User.User x) | `Error e -> `Error e
+  in
+  let printer fs = function
+    | User.Viewer -> str_printer fs "viewer"
+    | User x -> str_printer fs x
+  in
+  let user_conv = (parser, printer) in
   let doc = Arg.info ~doc:"User name" [ "user" ] in
-  Arg.(value & opt (some string) None & doc)
+  Arg.(value & opt user_conv Viewer & doc)
 
 let version =
   match Build_info.V1.version () with

lib/contributions.ml

@@ -3,9 +3,9 @@ module Json = Yojson.Safe
 let ( / ) a b = Json.Util.member b a
 
 let query user =
-  Format.sprintf
+  Format.asprintf
     {|query($from: DateTime!, $to: DateTime!) {
-   %s {
+   %a {
     login
     contributionsCollection(from: $from, to: $to) {
       issueContributions(first: 100) {
@@ -55,9 +55,7 @@ let query user =
     }
   }
 }|}
-    (match user with
-    | Some u -> Format.sprintf "user(login: %S)" u
-    | None -> "viewer")
+    User.query user
 
 let request ~period:(start, finish) ~user ~token =
   let variables = [ ("from", `String start); ("to", `String finish) ] in
@@ -143,17 +141,11 @@ let read_repos json =
      }
 
 let of_json ~from ~user json =
-  let username, contribs =
-    match user with
-    | Some username ->
-        let contribs = json / "data" / "user" / "contributionsCollection" in
-        (username, contribs)
-    | None ->
-        let username =
-          json / "data" / "viewer" / "login" |> Json.Util.to_string
-        in
-        let contribs = json / "data" / "viewer" / "contributionsCollection" in
-        (username, contribs)
+  let username =
+    json / "data" / User.response_field user / "login" |> Json.Util.to_string
+  in
+  let contribs =
+    json / "data" / User.response_field user / "contributionsCollection"
   in
   let items =
     read_issues (contribs / "issueContributions")

lib/contributions.mli

@@ -16,12 +16,9 @@ module Repo_map : Map.S with type key = string
 type t = { username : string; activity : item list Repo_map.t }
 
 val request :
-  period:string * string ->
-  user:string option ->
-  token:Token.t ->
-  Graphql.request
+  period:string * string -> user:User.t -> token:Token.t -> Graphql.request
 
-val of_json : from:string -> user:string option -> Yojson.Safe.t -> t
+val of_json : from:string -> user:User.t -> Yojson.Safe.t -> t
 (** We pass [from] again here so we can filter out anything that GitHub included by accident. *)
 
 val is_empty : t -> bool

test/lib/test_contributions.ml

@@ -84,9 +84,9 @@ module Testable = struct
 end
 
 let request ~user =
-  Format.sprintf
+  Format.asprintf
     {|query($from: DateTime!, $to: DateTime!) {
-   %s {
+   %a {
     login
     contributionsCollection(from: $from, to: $to) {
       issueContributions(first: 100) {
@@ -136,9 +136,7 @@ let request ~user =
     }
   }
 }|}
-    (match user with
-    | Some u -> Format.sprintf "user(login: %S)" u
-    | None -> "viewer")
+    User.query user
 
 let test_request =
   let make_test name ~period ~user ~token ~expected =
@@ -150,7 +148,7 @@ let test_request =
     (name, `Quick, test_fun)
   in
   [
-    (let user = None in
+    (let user = User.Viewer in
      make_test "no token" ~user ~token:"" ~period:("", "")
        ~expected:
          {
@@ -165,7 +163,7 @@ let test_request =
                    `Assoc [ ("from", `String ""); ("to", `String "") ] );
                ];
          });
-    (let user = Some "me" in
+    (let user = User.User "me" in
      make_test "no token" ~user ~token:"" ~period:("", "")
        ~expected:
          {
@@ -182,7 +180,7 @@ let test_request =
          });
   ]
 
-let or_viewer = function Some u -> u | None -> "gpetiot"
+let or_viewer = function User.User u -> u | Viewer -> "gpetiot"
 
 let activity_example ~user =
   Format.sprintf
@@ -305,8 +303,7 @@ let activity_example ~user =
   }
 }
 |}
-    (match user with Some _ -> "user" | None -> "viewer")
-    (user |> or_viewer)
+    (User.response_field user) (user |> or_viewer)
 
 let activity_example_json ~user =
   Yojson.Safe.from_string (activity_example ~user)
@@ -414,11 +411,11 @@ let test_of_json =
     (name, `Quick, test_fun)
   in
   [
-    (let user = None in
+    (let user = User.Viewer in
      make_test "no token" ~from:"" ~user
        (activity_example_json ~user)
        ~expected:(contributions_example ~user));
-    (let user = Some "gpetiot" in
+    (let user = User.User "gpetiot" in
      make_test "no token" ~from:"" ~user
        (activity_example_json ~user)
        ~expected:(contributions_example ~user));
@@ -439,7 +436,7 @@ let test_is_empty =
         { Contributions.username = ""; activity = Contributions.Repo_map.empty }
       ~expected:true;
     make_test "not empty"
-      ~input:(contributions_example ~user:None)
+      ~input:(contributions_example ~user:Viewer)
       ~expected:false;
   ]
 
@@ -458,7 +455,7 @@ let test_pp =
         { Contributions.username = ""; activity = Contributions.Repo_map.empty }
       ~expected:"(no activity)";
     make_test "not empty"
-      ~input:(contributions_example ~user:None)
+      ~input:(contributions_example ~user:Viewer)
       ~expected:
         "### gpetiot/config.ml\n\
          Created repository \