Add rudimentary parser for Git config files

cli/dune

@@ -1,8 +1,19 @@
-(executables
+(executable
  (libraries cohttp-lwt-unix gitlab-unix cmdliner otoml)
  (package lab)
- (public_names lab)
- (names main))
+ (public_name lab)
+ (modules main api config issue merge_request project user)
+ (name main))
+
+(executable
+ (name test_gitconfig)
+ (modules_without_implementation gitconfig_types)
+ (modules gitconfig_lexer gitconfig_types gitconfig_parser test_gitconfig))
+
+(ocamllex gitconfig_lexer)
+
+(menhir
+ (modules gitconfig_parser))
 
 (mdx
  (files lab.md)

cli/gitconfig_lexer.mll

@@ -0,0 +1,16 @@
+{
+open Gitconfig_parser
+
+exception Error of string
+}
+
+let whitespace = ['\t' ' ']*
+let eol = '\n' | "\r\n"
+let key = ['A'-'Z''a'-'z''0'-'9''_''-']+
+let value = [^'\n''\r']+
+let section_name = [^'['']']+
+
+rule token = parse
+| whitespace '[' (section_name as name) ']' whitespace eol { SECTIONHEADER name }
+| whitespace (key as key) whitespace '=' whitespace (value as value) eol { KEYVAL (key,value) }
+| eof { EOF }

cli/gitconfig_parser.mly

@@ -0,0 +1,24 @@
+%{
+%}
+
+%token <Gitconfig_types.binding> KEYVAL
+%token <string> SECTIONHEADER
+%token EOF
+
+%start config
+
+%type <Gitconfig_types.t> config
+%type <Gitconfig_types.binding> key_value
+
+%%
+config:
+| section* EOF { $1 }
+
+section:
+| section_header key_value* { $1, $2 }
+
+section_header:
+| SECTIONHEADER { $1 }
+
+key_value:
+| KEYVAL { $1 }

cli/gitconfig_types.mli

@@ -0,0 +1,5 @@
+type binding = string * string  (* Key/value pair *)
+
+type section = string * binding list (* Section name and contents *)
+
+type t = section list

cli/test_gitconfig.ml

@@ -0,0 +1,23 @@
+let print_config fmt config =
+  let open Format in
+  let rec print_bindings fmt = function
+  | [] -> ()
+  | (key, value) :: rem ->
+      fprintf fmt "\t%s = %s\n" key value;
+      print_bindings fmt rem
+  in
+  config |> List.iter (fun (name, bindings) ->
+      fprintf fmt "[%s]\n%a" name print_bindings bindings
+    )
+
+
+let () =
+  let lexbuf = Lexing.from_channel stdin in
+  try
+    let config = Gitconfig_parser.config Gitconfig_lexer.token lexbuf in
+    print_config Format.std_formatter config
+  with
+  | Gitconfig_lexer.Error msg ->
+      Printf.fprintf stderr "%s%!" msg
+  | Gitconfig_parser.Error ->
+      Printf.fprintf stderr "At offset %d: syntax error.\n%!" (Lexing.lexeme_start lexbuf)

dune-project

@@ -69,3 +69,4 @@ This library installs the JavaScript version, which uses [js_of_ocaml](http://oc
  (synopsis "GitLab cli")
  (description "Experimental GitLab cli in the style of GitHub's gh and hub commands."))
 
+(using menhir 2.1)