support for test code reuse

src/grader/grading.ml

@@ -142,6 +142,38 @@ let get_grade
       Toploop_ext.use_string ~print_outcome ~ppf_answer
         "module Report = Learnocaml_report" ;
       set_progress [%i"Launching the test bench."] ;
+
+      let () =
+
+         let mods : (string * string) list = (* list of pairs (path, content) *)
+          let open Learnocaml_exercise in
+          let files = File.dependencies (access File.depend exo) in
+          List.map (fun f -> let path = File.key f 
+                             and content = decipher f exo in
+                             (path,content)) files 
+        in
+        let ml_files, mli_files = 
+            List.partition (fun (s,_) -> match Filename.extension s with
+                                         | ".ml" -> true
+                                         | ".mli" -> false
+                                         | _ -> failwith "depend.txt (1)") mods 
+        in
+        let insert_dependencies_in_env (current_path,structure) =
+          let name = String.capitalize_ascii (Filename.(remove_extension (basename current_path))) in
+          handle_error (internal_error [%i"while loading users dependencies"]) @@
+          match List.find_opt (fun (path,_) -> path = current_path ^ "i") mli_files with 
+          | Some (_,signature) -> Toploop_ext.use_mod_string ~print_outcome ~ppf_answer 
+                                    ~modname:name 
+                                    ~sig_code:signature 
+                                    structure
+          | None -> Toploop_ext.use_mod_string ~print_outcome ~ppf_answer 
+                      ~modname:name 
+                      structure
+          in
+        List.iter insert_dependencies_in_env ml_files
+
+      in
+
       handle_error (internal_error [%i"while testing your solution"]) @@
       Toploop_ext.use_string ~print_outcome ~ppf_answer ~filename:(file "test.ml")
         (Learnocaml_exercise.(decipher File.test exo)) ;

src/repo/learnocaml_exercise.ml

@@ -17,24 +17,28 @@ type t =
     test : string ;
     solution : string ;
     max_score : int ;
+    depend : string ;
+    dependencies : string list;
   }
 
 let encoding =
   let open Json_encoding in
   conv
-    (fun { id; prelude; template; descr; prepare; test; solution; max_score } ->
-       id, prelude, template, descr, prepare, test, solution, max_score)
-    (fun (id, prelude, template, descr, prepare, test, solution, max_score) ->
-       { id ; prelude ; template ; descr ; prepare ; test ; solution ; max_score })
-    (obj8
+    (fun { id; prelude; template; descr; prepare; test; solution; max_score; depend; dependencies} ->
+       id, prelude, template, descr, prepare, test, solution, max_score,depend, dependencies)
+    (fun (id, prelude, template, descr, prepare, test, solution, max_score,depend, dependencies) ->
+       { id ; prelude ; template ; descr ; prepare ; test ; solution ; max_score ; depend ; dependencies})
+    (obj10
        (req "id" string)
        (req "prelude" string)
        (req "template" string)
        (req "descr" (list (tup2 string string)))
        (req "prepare" string)
        (req "test" string)
        (req "solution" string)
-       (req "max-score" int))
+       (req "max-score" int)
+       (req  "depend" string)
+       (req  "dependencies" (list string)))
 
 (* let meta_from_string m =
  *   Ezjsonm.from_string m
@@ -179,6 +183,29 @@ module File = struct
       update = (fun solution ex -> { ex with solution })
      }
 
+  let depend =
+    { key = "../depend.txt" ; ciphered = false ; (* does'nt work with ciphered = true *)
+      decode = (fun v -> v) ; encode = (fun v -> v) ;
+      field = (fun ex -> ex.depend) ;
+      update = (fun depend ex -> { ex with depend })
+     }
+
+  let dependencies dep = 
+    let extract_depend dep = 
+      (String.split_on_char '\n' dep)
+      |> (List.map String.trim)
+      |> List.filter (fun s -> String.length s > 0 && s.[0] <> '#') 
+    in
+    List.mapi (fun i lib_name ->
+                ({ key = lib_name ; ciphered = true ;
+                   decode = (fun v -> v) ; encode = (fun v -> v) ;
+                   field = (fun ex -> List.nth ex.dependencies i) ;
+                   update = (fun _ _ -> failwith "Learnocaml_exercise.dependencies")
+                 }))
+        (extract_depend dep)
+
+  let key f = f.key
+
   module MakeReader (Concur : Concur) = struct
     let read ~read_field ?id: ex_id ?(decipher = true) () =
       let open Concur in
@@ -292,7 +319,10 @@ module File = struct
           read_file prepare ;
           read_file solution ;
           read_file test ;
+          read_file depend ;
           (* read_max_score () *) ] >>= fun () ->
+      join (let dep = try get depend !ex with Missing_file _ -> "" in 
+            List.map read_file (dependencies dep)) >>= fun () ->
       return !ex
   end
 
@@ -324,7 +354,6 @@ let cipher f v ex =
   else
     f.update (f.encode v) ex
 
-
 let field_from_file file files =
   try File.(StringMap.find file.key files |> file.decode)
   with Not_found -> raise File.(Missing_file file.key)
@@ -335,6 +364,7 @@ module MakeReaderAnddWriter (Concur : Concur) = struct
     let open Concur in
     FileReader.read ~read_field ?id ?decipher () >>= fun ex ->
     try
+      let dep = try field_from_file File.depend ex with File.(Missing_file _) -> "" in
       return
         { id = field_from_file File.id ex;
           (* meta = field_from_file File.meta ex; *)
@@ -345,6 +375,8 @@ module MakeReaderAnddWriter (Concur : Concur) = struct
           test = field_from_file File.test ex ;
           solution = field_from_file File.solution ex ;
           max_score = 0 ;
+          depend = dep ;
+          dependencies = List.map (fun f -> field_from_file f ex) (File.dependencies dep) ;
         }
     with File.Missing_file _ as e -> fail e
 
@@ -366,8 +398,9 @@ module MakeReaderAnddWriter (Concur : Concur) = struct
         acc := nacc ;
         return ()
       with Not_found -> Concur.return () in
+      let d = decipher File.depend ex in
     join
-      [ write_field id ;
+      ([ write_field id ;
         (* write_field meta ;
          * write_field title ; *)
         write_field prelude ;
@@ -376,7 +409,10 @@ module MakeReaderAnddWriter (Concur : Concur) = struct
         write_field prepare ;
         write_field solution ;
         write_field test ;
-        (* write_field max_score *) ] >>= fun () ->
+        write_field depend ;
+        (* write_field max_score *) ] 
+        @ (List.map write_field (dependencies d)) )
+        >>= fun () ->
     return !acc
 end
 

src/repo/learnocaml_exercise.mli

@@ -66,6 +66,14 @@ module File : sig
   (** Returns the (public) [descr.html] *)
   val descr: (string * string) list file
 
+  (** Returns the (public) [../depend.txt] *)
+  val depend: string file
+
+  (** Returns the (public) dependencies *)
+  val dependencies: string -> string file list
+
+  (** Returns the key of a file *)
+  val key : 'a file -> string
 end
 
 (** Access a field from the exercise, using the [t] representation, without **