A more generic way to define elision

lib/backend.ml

@@ -274,7 +274,12 @@ module Performance = struct
     in
     let resp =
       (* TODO: make a cli-argument out of this instead of doing this always *)
-      let responses = List.map Merlin.Response.crop_value responses in
+      let responses =
+        List.map
+          (fun resp ->
+            Merlin.Response.(crop_value @@ crop_heap_and_cache @@ resp))
+          responses
+      in
       { Query_response.sample_id = id; cmd; responses }
     in
     let cmd = { Command.sample_id = id; cmd } in
@@ -381,7 +386,9 @@ let behavior config =
                  let responses =
                    List.map
                      (fun resp ->
-                       Merlin.Response.(strip_file @@ crop_timing @@ resp))
+                       Merlin.Response.(
+                         strip_file @@ crop_timing @@ crop_heap_and_cache
+                         @@ resp))
                      responses
                  in
                  { Query_response.sample_id = id; cmd; responses }

lib/merlin.ml

@@ -152,6 +152,20 @@ module Response = struct
 
   let yojson_of_t x = x
 
+  let crop_arbitrary_keys keys = function
+    | `Assoc answer ->
+        let cropped_answer =
+          List.fold_left
+            (fun answer key -> List.remove_assoc key answer)
+            answer keys
+        in
+        `Assoc cropped_answer
+    | _ ->
+        (* Fixme *)
+        failwith
+          "Error while cropping merlin response: reponse should be an \
+           association list."
+
   let get_timing = function
     | `Assoc answer -> (
         match List.assoc "timing" answer with
@@ -162,21 +176,11 @@ module Response = struct
         | _ -> failwith "merlin gave bad output")
     | _ -> failwith "merlin gave bad output"
 
-  let crop_timing = function
-    | `Assoc answer -> `Assoc (List.remove_assoc "timing" answer)
-    | _ ->
-        (* Fixme *)
-        failwith
-          "Error while cropping merlin response: reponse should have a key \
-           called timing."
+  let crop_timing answer = crop_arbitrary_keys [ "timing" ] answer
+  let crop_value answer = crop_arbitrary_keys [ "value" ] answer
 
-  let crop_value = function
-    | `Assoc answer -> `Assoc (List.remove_assoc "value" answer)
-    | _ ->
-        (* Fixme *)
-        failwith
-          "Error while cropping merlin response: reponse should have a key \
-           called value."
+  let crop_heap_and_cache answer =
+    crop_arbitrary_keys [ "cache"; "heap_mbytes" ] answer
 
   let strip_file = function
     | `Assoc l ->

lib/merlin.mli

@@ -91,6 +91,10 @@ module Response : sig
   (** Removes the value field from the merlin response, i.e. the actual response
       to the query. *)
 
+  val crop_heap_and_cache : t -> t
+  (** Removes the heap_mbytes and cache field from the merlin response, i.e. the
+      actual response to the query. *)
+
   val strip_file : t -> t
   (** In a Merlin response of the form [{"value":{"file":file_dir, ...}, ...}],
       where [file_dir] is a qualified file name, this strips off the directory