[#35] Refactor file tree type (#52)

* Refactor
* Refactor file tree type

* Refactor variable names

* Add motivation for storing file type and contents separately

* Resolve merge conflict

Author: loadre

lib/fs/fs.ml

@@ -1,8 +1,15 @@
 module Filec = Filec
 
 type tree =
-  | File of string * Filec.t Lazy.t * Filec.file_type Lazy.t
-  | Dir of string * tree array Lazy.t
+  | File of {
+      name : string;
+      contents : Filec.t Lazy.t;
+      file_type : Filec.file_type Lazy.t;
+    }
+  | Dir of {
+      name : string;
+      children : tree array Lazy.t;
+    }
 
 type dir_cursor = {
   pos : int;
@@ -15,8 +22,8 @@ type cursor =
 
 (* Extracts the file name from a tree node *)
 let file_name = function
-  | File (name, _, _) -> name
-  | Dir (name, _) -> name
+  | File { name; _ } -> name
+  | Dir { name; _ } -> name
 
 (* A files comparison:
 
@@ -30,10 +37,10 @@ let order_files t1 t2 =
   | _, _ -> String.compare (file_name t1) (file_name t2)
 
 let rec sort_tree = function
-  | File (name, contents, ft) -> File (name, contents, ft)
-  | Dir (name, (lazy children)) ->
+  | File _ as f -> f
+  | Dir { name; children = (lazy children) } ->
       Array.sort order_files children;
-      Dir (name, lazy (Array.map sort_tree children))
+      Dir { name; children = lazy (Array.map sort_tree children) }
 
 (* Recursively reads a directory tree *)
 let rec to_tree path =
@@ -44,13 +51,15 @@ let rec to_tree path =
            (fun child_name -> to_tree (Filename.concat path child_name))
            (Sys.readdir path))
     in
-    let dirname = Filename.basename path in
-    Dir (dirname, children)
+    let name = Filename.basename path in
+    Dir { name; children }
   else
     File
-      ( Filename.basename path,
-        lazy (Filec.read path),
-        lazy (Filec.type_of_path path) )
+      {
+        name = Filename.basename path;
+        contents = lazy (Filec.read path);
+        file_type = lazy (Filec.type_of_path path);
+      }
 
 let read_tree path = path |> to_tree |> sort_tree
 let file_at cursor = cursor.files.(cursor.pos)
@@ -100,12 +109,12 @@ let go_next zipper =
   | Dir_cursor cursor -> (
       let next = file_at cursor in
       match next with
-      | File (_name, contents, _) ->
+      | File { contents; _ } ->
           {
             parents = cursor :: zipper.parents;
             current = File_cursor (Lazy.force contents);
           }
-      | Dir (_, (lazy next)) ->
+      | Dir { children = (lazy next); _ } ->
           if Array.length next = 0 then zipper
           else
             {

lib/fs/fs.mli

@@ -2,10 +2,20 @@
     and current offsets. *)
 module Filec = Filec
 
+(* NOTE: contents and file_type are stored separately so we can know the file
+    type and assign a proper icon without reading the contents *)
+
 (** A definition of a file tree. *)
 type tree =
-  | File of string * Filec.t Lazy.t * Filec.file_type Lazy.t
-  | Dir of string * tree array Lazy.t
+  | File of {
+      name : string;
+      contents : Filec.t Lazy.t;
+      file_type : Filec.file_type Lazy.t;
+    }
+  | Dir of {
+      name : string;
+      children : tree array Lazy.t;
+    }
 
 (** Return the name of a given tree node. *)
 val file_name : tree -> string

lib/tui/tui.ml

@@ -29,10 +29,10 @@ let read_root_tree ~root_dir_path =
   let tree = Fs.read_tree root_dir_path in
   let files =
     match tree with
-    | Fs.File (path, _, _) ->
-        Printf.eprintf "Given path '%s' is not a directory!" path;
+    | Fs.File { name; _ } ->
+        Printf.eprintf "Given path '%s' is not a directory!" name;
         exit 1
-    | Fs.Dir (_, files) -> files
+    | Fs.Dir { children = files; _ } -> files
   in
   files
 

lib/tui/widget/code.ml

@@ -50,11 +50,11 @@ let max_file_name_len files =
 let fmt_file ~max_name_len (tree : Fs.tree) =
   let pad = Extra.String.fill_right max_name_len in
   match tree with
-  | File (name, _, file_type) -> (
+  | File { name; file_type; _ } -> (
       match Lazy.force file_type with
       | Fs.Filec.Text -> Pretty.Icon.file_char ^ " " ^ pad name
       | Fs.Filec.Binary -> Pretty.Icon.bin_char ^ " " ^ pad name)
-  | Dir (name, (lazy children)) -> (
+  | Dir { name; children = (lazy children) } -> (
       match children with
       | [||] -> Pretty.Icon.empty_dir_char ^ " " ^ pad name
       | _ -> Pretty.Icon.dir_char ^ " " ^ pad name)
@@ -189,8 +189,8 @@ let fs_to_view (fs : Fs.zipper) =
     | File_cursor contents, parent :: _ -> (parent, File_selected contents)
     | Dir_cursor cursor, _ -> (
         match Fs.file_at cursor with
-        | File (_, contents, _) -> (cursor, File_selected (Lazy.force contents))
-        | Dir (_, children) ->
+        | File { contents; _ } -> (cursor, File_selected (Lazy.force contents))
+        | Dir { children; _ } ->
             ( cursor,
               Dir_selected
                 {