Plugged the preprocessor into the compiler's CLI.

src/bin/cli.ml

@@ -152,6 +152,18 @@ let compile_file =
   let doc = "Subcommand: Compile a contract." in
   (Term.ret term , Term.info ~doc cmdname)
 
+let preprocess =
+  let f source_file syntax display_format = (
+    toplevel ~display_format @@
+      let%bind pp =
+        Compile.Of_source.preprocess source_file (Syntax_name syntax) in
+      ok @@ Format.asprintf "%s \n" (Buffer.contents pp)
+  ) in
+  let term = Term.(const f $ source_file 0 $ syntax $ display_format) in
+  let cmdname = "preprocess" in
+  let doc = "Subcommand: Preprocess the source file.\nWarning: Intended for development of LIGO and can break at any time." in
+  (Term.ret term, Term.info ~doc cmdname)
+
 let print_cst =
   let f source_file syntax display_format = (
     toplevel ~display_format @@
@@ -470,4 +482,5 @@ let run ?argv () =
     print_ast_typed ;
     print_mini_c ;
     list_declarations ;
+    preprocess
   ]

src/bin/expect_tests/help_tests.ml

@@ -53,6 +53,10 @@ let%expect_test _ =
            measure-contract
                Subcommand: Measure a contract's compiled size in bytes.
 
+           preprocess
+               Subcommand: Preprocess the source file. Warning: Intended for
+               development of LIGO and can break at any time.
+
            print-ast
                Subcommand: Print the AST. Warning: Intended for development of
                LIGO and can break at any time.
@@ -140,6 +144,10 @@ let%expect_test _ =
            measure-contract
                Subcommand: Measure a contract's compiled size in bytes.
 
+           preprocess
+               Subcommand: Preprocess the source file. Warning: Intended for
+               development of LIGO and can break at any time.
+
            print-ast
                Subcommand: Print the AST. Warning: Intended for development of
                LIGO and can break at any time.

src/main/compile/helpers.ml

@@ -148,18 +148,18 @@ let pretty_print_cameligo source =
       ~offsets:true
       ~mode:`Point
       ~buffer in
-  Parser.Cameligo.ParserLog.pp_ast state ast;
+  Parser_cameligo.ParserLog.pp_ast state ast;
   ok buffer
 
 let pretty_print_reasonligo source =
   let%bind ast = Parser.Reasonligo.parse_file source in
   let buffer = Buffer.create 59 in
   let state = (* TODO: Should flow from the CLI *)
-    Parser.Reasonligo.ParserLog.mk_state
+    Parser_cameligo.ParserLog.mk_state
       ~offsets:true
       ~mode:`Point
       ~buffer in
-  Parser.Reasonligo.ParserLog.pp_ast state ast;
+  Parser_cameligo.ParserLog.pp_ast state ast;
   ok buffer
 
 let pretty_print syntax source =
@@ -169,3 +169,17 @@ let pretty_print syntax source =
     PascaLIGO  -> pretty_print_pascaligo  source
   | CameLIGO   -> pretty_print_cameligo   source
   | ReasonLIGO -> pretty_print_reasonligo source
+
+let preprocess_pascaligo = Parser.Pascaligo.preprocess
+
+let preprocess_cameligo = Parser.Cameligo.preprocess
+
+let preprocess_reasonligo = Parser.Reasonligo.preprocess
+
+let preprocess syntax source =
+  let%bind v_syntax =
+    syntax_to_variant syntax (Some source) in
+  match v_syntax with
+    PascaLIGO  -> preprocess_pascaligo  source
+  | CameLIGO   -> preprocess_cameligo   source
+  | ReasonLIGO -> preprocess_reasonligo source

src/main/compile/of_source.ml

@@ -21,3 +21,6 @@ let compile_contract_input : string -> string -> v_syntax -> Ast_imperative.expr
 
 let pretty_print source_filename syntax =
   Helpers.pretty_print syntax source_filename
+
+let preprocess source_filename syntax =
+  Helpers.preprocess syntax source_filename

src/passes/1-parser/cameligo.ml

@@ -140,3 +140,7 @@ let parse_string source = apply (fun () -> Unit.contract_in_string source)
 (* Parsing an expression in a string *)
 
 let parse_expression source = apply (fun () -> Unit.expr_in_string source)
+
+(* Preprocessing a contract in a file *)
+
+let preprocess source = apply (fun () -> Unit.preprocess source)

src/passes/1-parser/cameligo.mli

@@ -0,0 +1,21 @@
+(** This file provides an interface to the CameLIGO parser. *)
+
+module AST = Parser_cameligo.AST
+
+(** Open a CameLIGO filename given by string and convert into an
+    abstract syntax tree. *)
+val parse_file : string -> AST.t Trace.result
+
+(** Convert a given string into a CameLIGO abstract syntax tree *)
+val parse_string : string -> AST.t Trace.result
+
+(** Parse a given string as a CameLIGO expression and return an
+    expression AST.
+
+    This is intended to be used for interactive interpreters, or other
+    scenarios where you would want to parse a CameLIGO expression
+    outside of a contract. *)
+val parse_expression : string -> AST.expr Trace.result
+
+(** Preprocess a given CameLIGO file and preprocess it. *)
+val preprocess : string -> Buffer.t Trace.result

src/passes/1-parser/pascaligo.ml

@@ -152,3 +152,7 @@ let parse_string source = apply (fun () -> Unit.contract_in_string source)
 (* Parsing an expression in a string *)
 
 let parse_expression source = apply (fun () -> Unit.expr_in_string source)
+
+(* Preprocessing a contract in a file *)
+
+let preprocess source = apply (fun () -> Unit.preprocess source)

src/passes/1-parser/pascaligo.mli

@@ -16,3 +16,6 @@ val parse_string : string -> AST.t Trace.result
     scenarios where you would want to parse a PascaLIGO expression
     outside of a contract. *)
 val parse_expression : string -> AST.expr Trace.result
+
+(** Preprocess a given PascaLIGO file and preprocess it. *)
+val preprocess : string -> Buffer.t Trace.result

src/passes/1-parser/reasonligo.ml

@@ -88,7 +88,7 @@ module Errors =
         ("location",
          fun () -> Format.asprintf "%a" Location.pp_lift @@ expression_loc)]
       in error ~data title message
-    
+(*
     let invalid_wild (expr: AST.expr) =
       let title () = "" in
       let message () =
@@ -99,7 +99,7 @@ module Errors =
         ("location",
          fun () -> Format.asprintf "%a" Location.pp_lift @@ expression_loc)]
       in error ~data title message
-
+ *)
   end
 
 let apply parser =
@@ -172,3 +172,7 @@ let parse_string source = apply (fun () -> Unit.contract_in_string source)
 (* Parsing an expression in a string *)
 
 let parse_expression source = apply (fun () -> Unit.expr_in_string source)
+
+(* Preprocessing a contract in a file *)
+
+let preprocess source = apply (fun () -> Unit.preprocess source)

src/passes/1-parser/reasonligo.mli

@@ -0,0 +1,21 @@
+(** This file provides an interface to the ReasonLIGO parser. *)
+
+module AST = Parser_cameligo.AST
+
+(** Open a ReasonLIGO filename given by string and convert into an
+    abstract syntax tree. *)
+val parse_file : string -> AST.t Trace.result
+
+(** Convert a given string into a ReasonLIGO abstract syntax tree *)
+val parse_string : string -> AST.t Trace.result
+
+(** Parse a given string as a ReasonLIGO expression and return an
+    expression AST.
+
+    This is intended to be used for interactive interpreters, or other
+    scenarios where you would want to parse a ReasonLIGO expression
+    outside of a contract. *)
+val parse_expression : string -> AST.expr Trace.result
+
+(** Preprocess a given ReasonLIGO file and preprocess it. *)
+val preprocess : string -> Buffer.t Trace.result

src/passes/1-parser/shared/ParserUnit.ml

@@ -265,4 +265,26 @@ module Make (Lexer: Lexer.S)
       let options = SubIO.make ~input:None ~expr:true in
       gen_parser options (Lexer.Channel stdin) parse_expr
 
+    (* Preprocess only *)
+
+    let preprocess (source : string) =
+      let options = SubIO.make ~input:(Some source) ~expr:false in
+      try
+        let cin     = open_in source in
+        let lexbuf  = Lexing.from_channel cin in
+        let () =
+          lexbuf.Lexing.lex_curr_p <-
+            {lexbuf.Lexing.lex_curr_p with pos_fname = source}
+        and options = (options :> Preprocessor.EvalOpt.options) in
+        match Preprocessor.Preproc.lex options lexbuf with
+          Stdlib.Ok _ as ok  -> ok
+        | Error (_, err) ->
+            let formatted =
+              Preproc.format ~offsets:options#offsets
+                             ~file:true
+                             err
+            in close_in cin; Stdlib.Error formatted
+      with Sys_error error ->
+             flush_all (); Stdlib.Error (Region.wrap_ghost error)
+
   end

src/passes/1-parser/shared/ParserUnit.mli

@@ -79,4 +79,7 @@ module Make (Lexer : Lexer.S)
 
     val expr_in_stdin :
       unit -> (AST.expr, message Region.reg) Stdlib.result
+
+    val preprocess :
+      string -> (Buffer.t, message Region.reg) Stdlib.result
 end

src/passes/2-concrete_to_imperative/cameligo.ml

@@ -120,7 +120,7 @@ module Errors = struct
     let data = [
         ("expression" ,
          (** TODO: The labelled arguments should be flowing from the CLI. *)
-       thunk @@ Parser.Cameligo.ParserLog.expr_to_string
+       thunk @@ Parser_cameligo.ParserLog.expr_to_string
                  ~offsets:true ~mode:`Point t)]
     in error ~data title message
 
@@ -996,7 +996,7 @@ and compile_cases : type a . (Raw.pattern * a) list -> (a, unit) matching_conten
          (** TODO: The labelled arguments should be flowing from the CLI. *)
         let content () =
           Printf.sprintf "Pattern : %s"
-                         (Parser.Cameligo.ParserLog.pattern_to_string
+                         (Parser_cameligo.ParserLog.pattern_to_string
                             ~offsets:true ~mode:`Point x) in
         error title content
       in