src/location.nit

   1 # This file is part of NIT ( http://www.nitlanguage.org ).
   2 #
   3 # Copyright 2009 Jean-Sebastien Gelinas <calestar@gmail.com>
   4 #
   5 # Licensed under the Apache License, Version 2.0 (the "License");
   6 # you may not use this file except in compliance with the License.
   7 # You may obtain a copy of the License at
   8 #
   9 #     http://www.apache.org/licenses/LICENSE-2.0
  10 #
  11 # Unless required by applicable law or agreed to in writing, software
  12 # distributed under the License is distributed on an "AS IS" BASIS,
  13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14 # See the License for the specific language governing permissions and
  15 # limitations under the License.
  16
  17 # This module is used to model Nit source-file and locations in source-file
  18 package location
  19
  20 # A raw text Nit source file
  21 class SourceFile
  22         # The path of the source
  23         var filename: String
  24
  25         # The content of the source
  26         var string: String
  27
  28         # Create a new sourcefile using a filename and a stream
  29         init(filename: String, stream: IStream)
  30         do
  31                 self.filename = filename
  32                 string = stream.read_all
  33                 line_starts[0] = 0
  34         end
  35
  36         # Create a new sourcefile using a dummy filename and a given content
  37         init from_string(filename: String, string: String)
  38         do
  39                 self.filename = filename
  40                 self.string = string
  41                 line_starts[0] = 0
  42         end
  43
  44         # Position of each line start
  45         var line_starts: Array[Int] = new Array[Int]
  46 end
  47
  48 # A location inside a source file
  49 class Location
  50         super Comparable
  51         redef type OTHER: Location
  52
  53         readable var _file: nullable SourceFile
  54         readable var _line_start: Int
  55         readable var _line_end: Int
  56         readable var _column_start: Int
  57         readable var _column_end: Int
  58
  59         init(f: nullable SourceFile, line_s: Int, line_e: Int, column_s: Int, column_e: Int) do
  60                 _file = f
  61                 _line_start = line_s
  62                 _line_end = line_e
  63                 _column_start = column_s
  64                 _column_end = column_e
  65         end
  66
  67         # The verbatim associated text in the source-file
  68         fun text: String
  69         do
  70                 var res = self.text_cache
  71                 if res != null then return res
  72                 var l = self
  73                 var pstart = l.file.line_starts[l.line_start-1] + l.column_start-1
  74                 var pend = l.file.line_starts[l.line_end-1] + l.column_end-1
  75                 res = l.file.string.substring(pstart, pend-pstart+1)
  76                 self.text_cache = res
  77                 return res
  78         end
  79
  80         private var text_cache: nullable String
  81
  82         init with_file(f: SourceFile) do init(f,0,0,0,0)
  83
  84         redef fun ==(other: nullable Object): Bool do
  85                 if other == null then return false
  86                 if not other isa Location then return false
  87
  88                 if other.file != file then return false
  89                 if other.line_start != line_start then return false
  90                 if other.line_end != line_end then return false
  91                 if other.column_start != column_start then return false
  92                 if other.column_end != column_end then return false
  93
  94                 return true
  95         end
  96
  97         fun located_in(loc: nullable Location): Bool do
  98                 if loc == null then return false
  99
 100                 if line_start < loc.line_start then return false
 101                 if line_start > loc.line_end then return false
 102
 103                 if line_end > loc.line_end then return false
 104
 105                 if line_start == loc.line_start then
 106                         if column_start < loc.column_start then return false
 107                         if column_start > loc.column_end then return false
 108                 end
 109
 110                 if line_end == loc.line_end and column_end > loc.column_end then return false
 111
 112                 return true
 113         end
 114
 115         redef fun to_s: String do
 116                 var file_part = ""
 117                 if file != null then
 118                         file_part = file.filename
 119                         if file.filename.length > 0 then file_part += ":"
 120                 end
 121
 122                 if line_start == line_end then
 123                         if column_start == column_end then
 124                                 return "{file_part}{line_start},{column_start}"
 125                         else
 126                                 return "{file_part}{line_start},{column_start}--{column_end}"
 127                         end
 128                 else
 129                         return "{file_part}{line_start},{column_start}--{line_end},{column_end}"
 130                 end
 131         end
 132
 133         fun relative_to(loc: nullable Location): String do
 134                 var relative: Location
 135                 if loc != null and loc.file == self.file then
 136                         relative = new Location(null, self.line_start, self.line_end, self.column_start, self.column_end)
 137                 else
 138                         relative = new Location(self.file, self.line_start, self.line_end, self.column_start, self.column_end)
 139                 end
 140                 return relative.to_s
 141         end
 142
 143         redef fun <(other: OTHER): Bool do
 144                 if self == other then return false
 145                 if self.located_in(other) then return true
 146                 if other.located_in(self) then return false
 147
 148                 if line_start != other.line_start then return line_start < other.line_start
 149                 if column_start != other.column_start then return column_start < other.column_start
 150                 if line_end != other.line_end then return line_end < other.line_end
 151
 152                 return column_end < other.column_end
 153         end
 154
 155         # Return the associated line with the location highlihted with color and a carret under the starting position
 156         # `color' must be and terminal escape sequence used as "{escape}[{color}m;"
 157         # "0;31" for red
 158         # "1;31" for bright red
 159         # "0;32" for green
 160         fun colored_line(color: String): String
 161         do
 162                 var esc = 27.ascii
 163                 var def = "{esc}[0m"
 164                 var col = "{esc}[{color}m"
 165
 166                 var l = self
 167                 var i = l.line_start
 168                 var line_start = l.file.line_starts[i-1]
 169                 var line_end = line_start
 170                 var string = l.file.string
 171                 while line_end+1 < string.length and string[line_end+1] != '\n' and string[line_end+1] != '\r' do
 172                         line_end += 1
 173                 end
 174                 var lstart = string.substring(line_start, l.column_start - 1)
 175                 var cend
 176                 if i != l.line_end then
 177                         cend = line_end - line_start + 1
 178                 else
 179                         cend = l.column_end
 180                 end
 181                 var lmid
 182                 var lend
 183                 if line_start + cend <= string.length then
 184                         lmid = string.substring(line_start + l.column_start - 1, cend - l.column_start + 1)
 185                         lend = string.substring(line_start + cend, line_end - line_start - cend + 1)
 186                 else
 187                         lmid = ""
 188                         lend = ""
 189                 end
 190                 var indent = new Buffer
 191                 for j in [line_start..line_start+l.column_start-1[ do
 192                         if string[j] == '\t' then
 193                                 indent.add '\t'
 194                         else
 195                                 indent.add ' '
 196                         end
 197                 end
 198                 return "\t{lstart}{col}{lmid}{def}{lend}\n\t{indent}^"
 199         end
 200 end
 201