internal refactoring

1. Rename most file path variables from [filename] to [path] and switch
   from type [string] to [Fpath.t]

```diff
- filename:string
+ path:Fpath.t
```

2. Extract some libraries into their own packages to reuse in other
   projects: loc, error-log, parsing-utils.

In the process of doing [2], the interface of the [fmt] command
changed slightly: now the extension is configured in the code and
doesn't need to be supplied in the dune files invocations.

For example:

```diff
  (with-stdout-to
    dune.inc.gen
    (pipe-stdout
-    (bash "%{bin:bopkit} fmt gen-dune .bop -- \%{bin:bopkit} fmt file")
+    (bash "%{bin:bopkit} fmt gen-dune -- \%{bin:bopkit} fmt file")
     (run dune format-dune-file)))))
```

bopkit.opam

@@ -13,16 +13,23 @@ depends: [
   "dune" {>= "3.11" & >= "3.11"}
   "ANSITerminal" {>= "0.8.3"}
   "appendable-list" {>= "v0.16" & < "v0.17"}
+  "auto-format" {>= "0.0.1"}
   "base" {>= "v0.16" & < "v0.17"}
   "bogue" {>= "20221112"}
   "command-unix-for-opam" {>= "0.0.1"}
   "core" {>= "v0.16" & < "v0.17"}
   "core_unix" {>= "v0.16" & < "v0.17"}
   "dune-site" {>= "3.11"}
+  "error-log" {>= "0.0.1"}
+  "fpath" {>= "0.7.3"}
+  "fpath-extended" {>= "0.0.2"}
   "graphics" {>= "5.1.2"}
+  "loc" {>= "0.0.1"}
   "mdx" {>= "2.2"}
   "menhir" {>= "20220210"}
+  "parsing-utils" {>= "0.0.1"}
   "pp" {>= "1.2.0"}
+  "pp-extended" {>= "0.0.1"}
   "ppx_jane" {>= "v0.16" & < "v0.17"}
   "ppx_js_style" {>= "v0.16" & < "v0.17"}
   "stdio" {>= "v0.16" & < "v0.17"}

doc/reference/dune

@@ -12,7 +12,7 @@
   (with-stdout-to
    dune.inc.gen
    (pipe-stdout
-    (bash "%{bin:bopkit} fmt gen-dune .bop -- \%{bin:bopkit} fmt file")
+    (bash "%{bin:bopkit} fmt gen-dune -- \%{bin:bopkit} fmt file")
     (run dune format-dune-file)))))
 
 (rule

dune-project

@@ -42,6 +42,8 @@
    (and
     (>= v0.16)
     (< v0.17)))
+  (auto-format
+   (>= 0.0.1))
   (base
    (and
     (>= v0.16)
@@ -60,14 +62,26 @@
     (< v0.17)))
   (dune-site
    (>= 3.11))
+  (error-log
+   (>= 0.0.1))
+  (fpath
+   (>= 0.7.3))
+  (fpath-extended
+   (>= 0.0.2))
   (graphics
    (>= 5.1.2))
+  (loc
+   (>= 0.0.1))
   (mdx
    (>= 2.2))
   (menhir
    (>= 20220210))
+  (parsing-utils
+   (>= 0.0.1))
   (pp
    (>= 1.2.0))
+  (pp-extended
+   (>= 0.0.1))
   (ppx_jane
    (and
     (>= v0.16)

editor/README.md

@@ -26,13 +26,13 @@ Checkout: bopkit fmt file -help
 
 ```sh
 $ bopkit fmt file -help
-autoformat a bopkit file
+autoformat bopkit files
 
   bopkit fmt file FILE
 
-This is a pretty-print command for bopkit files (extension *.bop).
+This is a pretty-print command for bopkit files (extensions .bop).
 
-This reads the contents of a bopkit file supplied in the command line, and
+This reads the contents of a file supplied in the command line, and
 pretty-print it on stdout, leaving the original file unchanged.
 
 If [-read-contents-from-stdin] is supplied, then the contents of the file is
@@ -44,18 +44,17 @@ to stdout, however the exit code will be non zero (typically [1]). Errors are
 printed on stderr.
 
 The hope for this command is for it to be compatible with editors and build
-systems so that you can integrate autoformatting of bopkit files into your
-workflow.
+systems so that you can integrate autoformatting of files into your workflow.
 
-It is used by [dune fmt] throughout the bopkit project, and has been tested
-with vscode. Because this command has been tested with a vscode extension that
-strips the last newline, a flag has been added to add an extra blank line,
-shall you run into this issue.
+Because this command has been tested with a vscode extension that strips the
+last newline, a flag has been added to add an extra blank line, shall you run
+into this issue.
 
 === flags ===
 
-  [-add-extra-blank-line]    . add an extra blank line at the end
-  [-read-contents-from-stdin]
+  [--add-extra-blank-line], -add-extra-blank-line
+                             . add an extra blank line at the end
+  [--read-contents-from-stdin], -read-contents-from-stdin
                              . read contents from stdin rather than from the
                                file
   [-help], -?                . print this help text and exit

lib/bit_utils/src/bit_array.ml

@@ -38,9 +38,9 @@ let to_string (t : t) =
   String.init (Array.length t) ~f:(fun i -> Bit_string_encoding.Bit.to_char t.(i))
 ;;
 
-let of_text_file ~filename =
+let of_text_file ~path =
   let q = Queue.create () in
-  In_channel.with_file filename ~f:(fun ic ->
+  In_channel.with_file (path |> Fpath.to_string) ~f:(fun ic ->
     with_return (fun { return } ->
       while true do
         match In_channel.input_line ic with
@@ -52,8 +52,8 @@ let of_text_file ~filename =
 
 let to_text_channel t oc = Printf.fprintf oc "%s\n" (to_string t)
 
-let to_text_file t ~filename =
-  Out_channel.with_file filename ~f:(fun oc -> to_text_channel t oc)
+let to_text_file t ~path =
+  Out_channel.with_file (path |> Fpath.to_string) ~f:(fun oc -> to_text_channel t oc)
 ;;
 
 let to_int bits =

lib/bit_utils/src/bit_array.mli

@@ -30,11 +30,11 @@ val to_string : t -> string
 
 (** Concat all the value read on all the lines from a file, using the function
     [of_01_chars_in_string]. *)
-val of_text_file : filename:string -> t
+val of_text_file : path:Fpath.t -> t
 
 (** Write a bunch of '0' and '1' to a file, ending with a newline character.
     This erases the previous contents of the file if it existed. *)
-val to_text_file : t -> filename:string -> unit
+val to_text_file : t -> path:Fpath.t -> unit
 
 val to_text_channel : t -> Out_channel.t -> unit
 

lib/bit_utils/src/bit_matrix.ml

@@ -14,8 +14,8 @@ let of_bit_array ~dimx ~dimy code =
   init_matrix_linear ~dimx ~dimy ~f:(fun i -> i < len && code.(i))
 ;;
 
-let of_text_file ~dimx ~dimy ~filename =
-  of_bit_array ~dimx ~dimy (Bit_array.of_text_file ~filename)
+let of_text_file ~dimx ~dimy ~path =
+  of_bit_array ~dimx ~dimy (Bit_array.of_text_file ~path)
 ;;
 
 let to_text_channel t oc =
@@ -24,8 +24,8 @@ let to_text_channel t oc =
     Out_channel.newline oc)
 ;;
 
-let to_text_file t ~filename =
-  Out_channel.with_file filename ~f:(fun oc -> to_text_channel t oc)
+let to_text_file t ~path =
+  Out_channel.with_file (path |> Fpath.to_string) ~f:(fun oc -> to_text_channel t oc)
 ;;
 
 let dimx t = Array.length t

lib/bit_utils/src/bit_matrix.mli

@@ -15,11 +15,11 @@ val init_matrix_linear : dimx:int -> dimy:int -> f:(int -> 'a) -> 'a array array
 val of_bit_array : dimx:int -> dimy:int -> Bit_array.t -> t
 
 (** See {!val:Bit_array.of_text_file}. *)
-val of_text_file : dimx:int -> dimy:int -> filename:string -> t
+val of_text_file : dimx:int -> dimy:int -> path:Fpath.t -> t
 
 (** Save it to disk. To make things more readable, write things line by line in
     the file (along the dimx dimension). *)
-val to_text_file : t -> filename:string -> unit
+val to_text_file : t -> path:Fpath.t -> unit
 
 val to_text_channel : t -> Out_channel.t -> unit
 

lib/bit_utils/src/dune

@@ -3,6 +3,6 @@
  (public_name bopkit.bit-utils)
  (wrapped false)
  (flags :standard -w +a-4-40-41-42-44-45-66 -warn-error +a -open Core)
- (libraries core)
+ (libraries core fpath)
  (preprocess
   (pps ppx_jane ppx_js_style -check-doc-comments)))

lib/bit_utils/src/partial_bit_array.ml

@@ -19,9 +19,9 @@ let to_string t =
   String.init (Array.length t) ~f:(fun i -> Bit_string_encoding.Bit_option.to_char t.(i))
 ;;
 
-let of_text_file ~filename =
+let of_text_file ~path =
   let q = Queue.create () in
-  In_channel.with_file filename ~f:(fun ic ->
+  In_channel.with_file (path |> Fpath.to_string) ~f:(fun ic ->
     with_return (fun { return } ->
       while true do
         match In_channel.input_line ic with
@@ -36,8 +36,8 @@ let of_text_file ~filename =
 
 let to_text_channel t oc = Printf.fprintf oc "%s\n" (to_string t)
 
-let to_text_file t ~filename =
-  Out_channel.with_file filename ~f:(fun oc -> to_text_channel t oc)
+let to_text_file t ~path =
+  Out_channel.with_file (path |> Fpath.to_string) ~f:(fun oc -> to_text_channel t oc)
 ;;
 
 let conflicts t ~with_:bits =

lib/bit_utils/src/partial_bit_array.mli

@@ -15,10 +15,10 @@ val of_01star_chars_in_string : string -> t
 val to_string : t -> string
 
 (** See {!val:Bit_array.of_text_file}. *)
-val of_text_file : filename:string -> t
+val of_text_file : path:Fpath.t -> t
 
 (** Save to disk, ends with a newline. *)
-val to_text_file : t -> filename:string -> unit
+val to_text_file : t -> path:Fpath.t -> unit
 
 val to_text_channel : t -> Out_channel.t -> unit
 

lib/bit_utils/src/partial_bit_matrix.ml

@@ -6,8 +6,8 @@ let of_partial_bit_array ~dimx ~dimy code =
     if i < len then code.(i) else None)
 ;;
 
-let of_text_file ~dimx ~dimy ~filename =
-  of_partial_bit_array ~dimx ~dimy (Partial_bit_array.of_text_file ~filename)
+let of_text_file ~dimx ~dimy ~path =
+  of_partial_bit_array ~dimx ~dimy (Partial_bit_array.of_text_file ~path)
 ;;
 
 let to_text_channel t oc =
@@ -16,6 +16,6 @@ let to_text_channel t oc =
     Out_channel.newline oc)
 ;;
 
-let to_text_file t ~filename =
-  Out_channel.with_file filename ~f:(fun oc -> to_text_channel t oc)
+let to_text_file t ~path =
+  Out_channel.with_file (path |> Fpath.to_string) ~f:(fun oc -> to_text_channel t oc)
 ;;

lib/bit_utils/src/partial_bit_matrix.mli

@@ -8,7 +8,7 @@ type t = Partial_bit_array.t array [@@deriving compare, equal, sexp_of]
 val of_partial_bit_array : dimx:int -> dimy:int -> Partial_bit_array.t -> t
 
 (** See {!val:Partial_bit_array.of_text_file}. *)
-val of_text_file : dimx:int -> dimy:int -> filename:string -> t
+val of_text_file : dimx:int -> dimy:int -> path:Fpath.t -> t
 
-val to_text_file : t -> filename:string -> unit
+val to_text_file : t -> path:Fpath.t -> unit
 val to_text_channel : t -> Out_channel.t -> unit

lib/bit_utils/test/dune

@@ -6,7 +6,8 @@
   core
   core_unix
   core_unix.filename_unix
-  expect_test_helpers_core)
+  expect_test_helpers_core
+  fpath)
  (inline_tests)
  (preprocess
   (pps ppx_jane ppx_js_style -check-doc-comments)))

lib/bit_utils/test/test__bit_array.ml

@@ -43,10 +43,10 @@ let%expect_test "to_string roundtrip" =
 
 let%expect_test "text files" =
   let test t =
-    let filename = Filename_unix.temp_file "test__bit_array" "text" in
-    Bit_array.to_text_file t ~filename;
-    let contents = In_channel.read_all filename in
-    let t2 = Bit_array.of_text_file ~filename in
+    let path = Filename_unix.temp_file "test__bit_array" "text" |> Fpath.v in
+    Bit_array.to_text_file t ~path;
+    let contents = In_channel.read_all (path |> Fpath.to_string) in
+    let t2 = Bit_array.of_text_file ~path in
     if not ([%equal: Bit_array.t] t t2)
     then raise_s [%sexp "Value does not roundtrip", { t : Bit_array.t; t2 : Bit_array.t }];
     let contents2 = Bit_array.to_string t ^ "\n" in
@@ -55,7 +55,7 @@ let%expect_test "text files" =
       raise_s
         [%sexp "String contents not equal", { contents : string; contents2 : string }];
     print_endline contents;
-    Core_unix.unlink filename
+    Core_unix.unlink (path |> Fpath.to_string)
   in
   test [||];
   [%expect {||}];

lib/bit_utils/test/test__bit_matrix.ml

@@ -38,13 +38,13 @@ let%expect_test "of_bit_array" =
 ;;
 
 let%expect_test "of_text_file" =
-  let filename = Filename_unix.temp_file "test__bit_matrix" "text" in
-  Out_channel.with_file filename ~f:(fun oc ->
+  let path = Filename_unix.temp_file "test__bit_matrix" "text" |> Fpath.v in
+  Out_channel.with_file (path |> Fpath.to_string) ~f:(fun oc ->
     Printf.fprintf oc "// Hello comment\n";
     Printf.fprintf oc "010101010101\n";
     Printf.fprintf oc "011111111110\n");
   let test ~dimx ~dimy =
-    let t = Bit_matrix.of_text_file ~dimx ~dimy ~filename in
+    let t = Bit_matrix.of_text_file ~dimx ~dimy ~path in
     Bit_matrix.to_text_channel t stdout
   in
   test ~dimx:2 ~dimy:12;
@@ -63,6 +63,6 @@ let%expect_test "of_text_file" =
     0101
     0101
     0111 |}];
-  Core_unix.unlink filename;
+  Core_unix.unlink (path |> Fpath.to_string);
   ()
 ;;

lib/bit_utils/test/test__partial_bit_array.ml

@@ -44,10 +44,10 @@ let%expect_test "to_string roundtrip" =
 
 let%expect_test "text files" =
   let test t =
-    let filename = Filename_unix.temp_file "test__bit_array" "text" in
-    Partial_bit_array.to_text_file t ~filename;
-    let contents = In_channel.read_all filename in
-    let t2 = Partial_bit_array.of_text_file ~filename in
+    let path = Filename_unix.temp_file "test__bit_array" "text" |> Fpath.v in
+    Partial_bit_array.to_text_file t ~path;
+    let contents = In_channel.read_all (path |> Fpath.to_string) in
+    let t2 = Partial_bit_array.of_text_file ~path in
     if not ([%equal: Partial_bit_array.t] t t2)
     then
       raise_s
@@ -60,7 +60,7 @@ let%expect_test "text files" =
       raise_s
         [%sexp "String contents not equal", { contents : string; contents2 : string }];
     print_endline contents;
-    Core_unix.unlink filename
+    Core_unix.unlink (path |> Fpath.to_string)
   in
   test [||];
   [%expect {||}];

lib/bit_utils/test/test__partial_bit_matrix.ml

@@ -24,13 +24,13 @@ let%expect_test "of_partial_bit_array" =
 ;;
 
 let%expect_test "of_text_file" =
-  let filename = Filename_unix.temp_file "test__bit_matrix" "text" in
-  Out_channel.with_file filename ~f:(fun oc ->
+  let path = Filename_unix.temp_file "test__bit_matrix" "text" |> Fpath.v in
+  Out_channel.with_file (path |> Fpath.to_string) ~f:(fun oc ->
     Printf.fprintf oc "// Hello comment\n";
     Printf.fprintf oc "010*010*01*1\n";
     Printf.fprintf oc "0**111*11110\n");
   let test ~dimx ~dimy =
-    let t = Partial_bit_matrix.of_text_file ~dimx ~dimy ~filename in
+    let t = Partial_bit_matrix.of_text_file ~dimx ~dimy ~path in
     Partial_bit_matrix.to_text_channel t stdout
   in
   test ~dimx:2 ~dimy:12;
@@ -49,6 +49,6 @@ let%expect_test "of_text_file" =
     010*
     01*1
     0**1 |}];
-  Core_unix.unlink filename;
+  Core_unix.unlink (path |> Fpath.to_string);
   ()
 ;;

lib/bopkit/src/comments.ml

@@ -1,11 +1,12 @@
-type t = Comment.t list Comments_state.Comment_node.t [@@deriving equal, sexp_of]
+type t = Comment.t list Parsing_utils.Comments_state.Comment_node.t
+[@@deriving equal, sexp_of]
 
-let value t = Comments_state.Comment_node.value_exn t
+let value t = Parsing_utils.Comments_state.Comment_node.value_exn t
 let is_empty t = List.is_empty (value t)
 
 let make ~attached_to =
-  Comments_state.comment_node ~attached_to ~f:(fun comments ->
+  Parsing_utils.Comments_state.comment_node ~attached_to ~f:(fun comments ->
     List.map comments ~f:Comment.parse_exn)
 ;;
 
-let none = Comments_state.Comment_node.return []
+let none = Parsing_utils.Comments_state.Comment_node.return []

lib/bopkit/src/dune

@@ -2,6 +2,14 @@
  (name bopkit)
  (public_name bopkit.bopkit)
  (flags :standard -w +a-4-40-41-42-44-45-66 -warn-error +a -open Base)
- (libraries appendable-list base bit_utils error_log parsing_utils pp)
+ (libraries
+  appendable-list
+  base
+  bit_utils
+  error-log
+  fpath
+  fpath-extended
+  parsing-utils
+  pp)
  (preprocess
   (pps ppx_jane ppx_js_style -check-doc-comments)))