Add command line option to print comment table (#560)

* Add command line option to print comment table

* Remove @@LiVe annotation from Res_comments_table.log

Author: cknitt

README.md

@@ -65,6 +65,7 @@ Debug a file:
 # write code in test.res
 dune exec -- rescript test.res # test printer
 dune exec -- rescript -print ast test.res # print ast
+dune exec -- rescript -print comments test.res # print comment table
 dune exec -- rescript -print ml test.res # show ocaml code
 dune exec -- rescript -print res -width 80 test.res # test printer and change default print width
 ```

cli/res_cli.ml

@@ -190,7 +190,7 @@ end = struct
   let spec = [
     ("-recover", Arg.Unit (fun () -> recover := true), "Emit partial ast");
     ("-parse", Arg.String (fun txt -> origin := txt), "Parse reasonBinary, ml or res. Default: res");
-    ("-print", Arg.String (fun txt -> print := txt), "Print either binary, ml, ast, sexp or res. Default: res");
+    ("-print", Arg.String (fun txt -> print := txt), "Print either binary, ml, ast, sexp, comments or res. Default: res");
     ("-width", Arg.Int (fun w -> width := w), "Specify the line length for the printer (formatter)");
     ("-interface", Arg.Unit (fun () -> interface := true), "Parse as interface");
     ("-ppx", Arg.String (fun txt -> ppx := txt), "Apply a specific built-in ppx before parsing, none or jsx. Default: none");
@@ -229,9 +229,10 @@ module CliArgProcessor = struct
       | "ml" -> Res_driver_ml_parser.printEngine
       | "ast" -> Res_ast_debugger.printEngine
       | "sexp" -> Res_ast_debugger.sexpPrintEngine
+      | "comments" -> Res_ast_debugger.commentsPrintEngine
       | "res"  -> Res_driver.printEngine
       | target ->
-        print_endline ("-print needs to be either binary, ml, ast, sexp or res. You provided " ^ target);
+        print_endline ("-print needs to be either binary, ml, ast, sexp, comments or res. You provided " ^ target);
         exit 1
     in
 

src/res_ast_debugger.ml

@@ -1,4 +1,5 @@
 module Doc = Res_doc
+module CommentTable = Res_comments_table
 
 let printEngine = Res_driver.{
   printImplementation = begin fun ~width:_ ~filename:_ ~comments:_ structure ->
@@ -1236,3 +1237,17 @@ module SexpAst = struct
 end
 
 let sexpPrintEngine = SexpAst.printEngine
+
+let commentsPrintEngine =
+  {
+    Res_driver.printImplementation =
+      (fun ~width:_ ~filename:_ ~comments s ->
+        let cmtTbl = CommentTable.make () in
+        CommentTable.walkStructure s cmtTbl comments;
+        CommentTable.log cmtTbl);
+    printInterface =
+      (fun ~width:_ ~filename:_ ~comments s ->
+        let cmtTbl = CommentTable.make () in
+        CommentTable.walkSignature s cmtTbl comments;
+        CommentTable.log cmtTbl);
+  }

src/res_ast_debugger.mli

@@ -1,8 +1,3 @@
-
-
-
 val printEngine : Res_driver.printEngine
-
-
 val sexpPrintEngine : Res_driver.printEngine
-
+val commentsPrintEngine : Res_driver.printEngine

src/res_comments_table.ml

@@ -79,7 +79,6 @@ let log t =
          Doc.line;
        ])
   |> Doc.toString ~width:80 |> print_endline
-  [@@live]
 
 let attach tbl loc comments =
   match comments with