hphp/hack/src/parser/full_fidelity_editable_trivia.ml

   1 (*
   2  * Copyright (c) 2016, Facebook, Inc.
   3  * All rights reserved.
   4  *
   5  * This source code is licensed under the MIT license found in the
   6  * LICENSE file in the "hack" directory of this source tree.
   7  *
   8  *)
   9
  10 (**
  11  * An editable trivia contains the text of the trivia; these trivia are not
  12  * backed by a source text, like the positioned trivia are.
  13  *)
  14
  15 module TriviaKind = Full_fidelity_trivia_kind
  16 module PositionedTrivia = Full_fidelity_positioned_trivia
  17 module SourceText = Full_fidelity_source_text
  18
  19 type t = {
  20   kind: TriviaKind.t;
  21   text: string;
  22 }
  23 [@@deriving show]
  24
  25 let make_ignore_error source_text offset width =
  26   {
  27     kind = TriviaKind.IgnoreError;
  28     text = SourceText.sub source_text offset width;
  29   }
  30
  31 let make_extra_token_error source_text offset width =
  32   {
  33     kind = TriviaKind.ExtraTokenError;
  34     text = SourceText.sub source_text offset width;
  35   }
  36
  37 let make_fallthrough source_text offset width =
  38   {
  39     kind = TriviaKind.FallThrough;
  40     text = SourceText.sub source_text offset width;
  41   }
  42
  43 let make_fix_me source_text offset width =
  44   { kind = TriviaKind.FixMe; text = SourceText.sub source_text offset width }
  45
  46 let make_whitespace source_text offset width =
  47   {
  48     kind = TriviaKind.WhiteSpace;
  49     text = SourceText.sub source_text offset width;
  50   }
  51
  52 let make_eol source_text offset width =
  53   {
  54     kind = TriviaKind.EndOfLine;
  55     text = SourceText.sub source_text offset width;
  56   }
  57
  58 let make_single_line_comment source_text offset width =
  59   {
  60     kind = TriviaKind.SingleLineComment;
  61     text = SourceText.sub source_text offset width;
  62   }
  63
  64 let make_delimited_comment source_text offset width =
  65   {
  66     kind = TriviaKind.DelimitedComment;
  67     text = SourceText.sub source_text offset width;
  68   }
  69
  70 let make_after_halt_compiler source_text offset width =
  71   {
  72     kind = TriviaKind.AfterHaltCompiler;
  73     text = SourceText.sub source_text offset width;
  74   }
  75
  76 (* HackFormat is using this to create trivia. It's deeply manipulating strings
  77  * so it was easier to create this helper function to avoid ad-hoc
  78  * SourceText construction.*)
  79 let create_delimited_comment text =
  80   { kind = TriviaKind.DelimitedComment; text }
  81
  82 let width trivia = String.length trivia.text
  83
  84 let kind trivia = trivia.kind
  85
  86 let text trivia = trivia.text
  87
  88 let text_from_trivia_list trivia_list =
  89   (* TODO: Better way to accumulate a string? *)
  90   let folder str trivia = str ^ text trivia in
  91   List.fold_left folder "" trivia_list
  92
  93 let from_positioned source_text positioned_trivia offset =
  94   let kind = PositionedTrivia.kind positioned_trivia in
  95   let width = PositionedTrivia.width positioned_trivia in
  96   let text = SourceText.sub source_text offset width in
  97   { kind; text }
  98
  99 let from_positioned_list source_text ts offset =
 100   let rec aux acc ts offset =
 101     match ts with
 102     | [] -> acc
 103     | h :: t ->
 104       let et = from_positioned source_text h offset in
 105       aux (et :: acc) t (offset + PositionedTrivia.width h)
 106   in
 107   List.rev (aux [] ts offset)
 108
 109 let to_json trivia =
 110   Hh_json.(
 111     JSON_Object
 112       [
 113         ("kind", JSON_String (TriviaKind.to_string trivia.kind));
 114         ("text", JSON_String trivia.text);
 115       ])