clean code

.ocamlformat

@@ -1,4 +1,4 @@
-version=0.24.1
+version=0.26.1
 assignment-operator=end-line
 break-cases=fit
 break-fun-decl=wrap
@@ -24,8 +24,9 @@ let-and=sparse
 let-binding-spacing=compact
 let-module=compact
 margin=80
-max-indent=68
+max-indent=2
 module-item-spacing=sparse
+ocaml-version=4.14.0
 ocp-indent-compat=false
 parens-ite=false
 parens-tuple=always

src/ccbg.ml

@@ -7,7 +7,6 @@ module App_id = struct
 end
 
 module Project_dirs = Directories.Project_dirs (App_id)
-
 module User_dirs = Directories.User_dirs ()
 
 let error msg =
@@ -52,7 +51,7 @@ let mode =
     | ("center" | "fill" | "fit" | "solid_color" | "stretch" | "tile") as mode
       ->
       mode
-    | invalid_mode -> error (Format.sprintf "invalid mode `%s`" invalid_mode) )
+    | invalid_mode -> Format.ksprintf error "invalid mode `%s`" invalid_mode )
 
 let wallpaper_files =
   match Bos.OS.Dir.contents (Fpath.v wallpaper_dir) with
@@ -60,13 +59,19 @@ let wallpaper_files =
   | Ok cnt -> (
     (* remove directories from the list... *)
     let cnt =
-      List.filter
+      List.filter_map
         (fun path ->
-          match Bos.OS.Dir.exists path with Ok b -> not b | _ -> false )
+          match Bos.OS.Dir.exists path with
+          | Ok is_dir ->
+            if is_dir then None
+            else
+              let path = Fpath.to_string path in
+              Some path
+          | _ -> None )
         cnt
     in
-    match Array.of_list (List.map Fpath.to_string cnt) with
-    | [||] -> error (Format.sprintf "no wallpaper found in %s" wallpaper_dir)
+    match Array.of_list cnt with
+    | [||] -> Format.ksprintf error "no wallpaper found in %s" wallpaper_dir
     | wallpaper_files -> wallpaper_files )
 
 let random_wallpaper =