class Prism::Location

This represents a location in the source.

Attributes

length[R]

The length of this location in bytes.

source[R]

A Source object that is used to determine more information from the given offset and length.

start_offset[R]

The byte offset from the beginning of the source where this location starts.

Public Class Methods

new(source, start_offset, length) click to toggle source

Create a new location object with the given source, start byte offset, and byte length.

# File lib/prism/parse_result.rb, line 171
def initialize(source, start_offset, length)
  @source = source
  @start_offset = start_offset
  @length = length

  # These are used to store comments that are associated with this location.
  # They are initialized to `nil` to save on memory when there are no
  # comments to be attached and/or the comment-related APIs are not used.
  @leading_comments = nil
  @trailing_comments = nil
end

Public Instance Methods

==(other) click to toggle source

Returns true if the given other location is equal to this location.

# File lib/prism/parse_result.rb, line 335
def ==(other)
  Location === other &&
    other.start_offset == start_offset &&
    other.end_offset == end_offset
end

adjoin(string) click to toggle source

Join this location with the first occurrence of the string in the source that occurs after this location on the same line, and return the new location. This will raise an error if the string does not exist.

# File lib/prism/parse_result.rb, line 354
def adjoin(string)
  line_suffix = source.slice(end_offset, source.line_end(end_offset) - end_offset)

  line_suffix_index = line_suffix.byteindex(string)
  raise "Could not find #{string}" if line_suffix_index.nil?

  Location.new(source, start_offset, length + line_suffix_index + string.bytesize)
end

chop() click to toggle source

Returns a new location that is the result of chopping off the last byte.

# File lib/prism/parse_result.rb, line 217
def chop
  copy(length: length == 0 ? length : length - 1)
end

comments() click to toggle source

Returns all comments that are associated with this location (both leading and trailing comments).

# File lib/prism/parse_result.rb, line 207
def comments
  [*@leading_comments, *@trailing_comments]
end

copy(source: self.source, start_offset: self.start_offset, length: self.length) click to toggle source

Create a new location object with the given options.

# File lib/prism/parse_result.rb, line 212
def copy(source: self.source, start_offset: self.start_offset, length: self.length)
  Location.new(source, start_offset, length)
end

deconstruct_keys(keys) click to toggle source

Implement the hash pattern matching interface for Location.

# File lib/prism/parse_result.rb, line 325
def deconstruct_keys(keys)
  { start_offset: start_offset, end_offset: end_offset }
end

end_character_column() click to toggle source

The column number in characters where this location ends from the start of the line.

# File lib/prism/parse_result.rb, line 314
def end_character_column
  source.character_column(end_offset)
end

end_character_offset() click to toggle source

The character offset from the beginning of the source where this location ends.

# File lib/prism/parse_result.rb, line 263
def end_character_offset
  source.character_offset(end_offset)
end

end_code_units_column(encoding = Encoding::UTF_16LE) click to toggle source

The column number in code units of the given encoding where this location ends from the start of the line.

# File lib/prism/parse_result.rb, line 320
def end_code_units_column(encoding = Encoding::UTF_16LE)
  source.code_units_column(end_offset, encoding)
end

end_code_units_offset(encoding = Encoding::UTF_16LE) click to toggle source

The offset from the start of the file in code units of the given encoding.

# File lib/prism/parse_result.rb, line 268
def end_code_units_offset(encoding = Encoding::UTF_16LE)
  source.code_units_offset(end_offset, encoding)
end

end_column() click to toggle source

The column number in bytes where this location ends from the start of the line.

# File lib/prism/parse_result.rb, line 308
def end_column
  source.column(end_offset)
end

end_line() click to toggle source

The line number where this location ends.

# File lib/prism/parse_result.rb, line 284
def end_line
  source.line(end_offset)
end

end_offset() click to toggle source

The byte offset from the beginning of the source where this location ends.

# File lib/prism/parse_result.rb, line 257
def end_offset
  start_offset + length
end

inspect() click to toggle source

Returns a string representation of this location.

# File lib/prism/parse_result.rb, line 222
def inspect
  "#<Prism::Location @start_offset=#{@start_offset} @length=#{@length} start_line=#{start_line}>"
end

join(other) click to toggle source

Returns a new location that stretches from this location to the given other location. Raises an error if this location is not before the other location or if they don’t share the same source.

# File lib/prism/parse_result.rb, line 344
def join(other)
  raise "Incompatible sources" if source != other.source
  raise "Incompatible locations" if start_offset > other.start_offset

  Location.new(source, start_offset, other.end_offset - start_offset)
end

leading_comment(comment) click to toggle source

Attach a comment to the leading comments of this location.

# File lib/prism/parse_result.rb, line 190
def leading_comment(comment)
  leading_comments << comment
end

leading_comments() click to toggle source

These are the comments that are associated with this location that exist before the start of this location.

# File lib/prism/parse_result.rb, line 185
def leading_comments
  @leading_comments ||= []
end

pretty_print(q) click to toggle source

Implement the pretty print interface for Location.

# File lib/prism/parse_result.rb, line 330
def pretty_print(q)
  q.text("(#{start_line},#{start_column})-(#{end_line},#{end_column})")
end

slice() click to toggle source

The source code that this location represents.

# File lib/prism/parse_result.rb, line 232
def slice
  source.slice(start_offset, length)
end

slice_lines() click to toggle source

The source code that this location represents starting from the beginning of the line that this location starts on to the end of the line that this location ends on.

# File lib/prism/parse_result.rb, line 239
def slice_lines
  line_start = source.line_start(start_offset)
  line_end = source.line_end(end_offset)
  source.slice(line_start, line_end - line_start)
end

source_lines() click to toggle source

Returns all of the lines of the source code associated with this location.

# File lib/prism/parse_result.rb, line 227
def source_lines
  source.lines
end

start_character_column() click to toggle source

The column number in characters where this location ends from the start of the line.

# File lib/prism/parse_result.rb, line 296
def start_character_column
  source.character_column(start_offset)
end

start_character_offset() click to toggle source

The character offset from the beginning of the source where this location starts.

# File lib/prism/parse_result.rb, line 247
def start_character_offset
  source.character_offset(start_offset)
end

start_code_units_column(encoding = Encoding::UTF_16LE) click to toggle source

The column number in code units of the given encoding where this location starts from the start of the line.

# File lib/prism/parse_result.rb, line 302
def start_code_units_column(encoding = Encoding::UTF_16LE)
  source.code_units_column(start_offset, encoding)
end

start_code_units_offset(encoding = Encoding::UTF_16LE) click to toggle source

The offset from the start of the file in code units of the given encoding.

# File lib/prism/parse_result.rb, line 252
def start_code_units_offset(encoding = Encoding::UTF_16LE)
  source.code_units_offset(start_offset, encoding)
end

start_column() click to toggle source

The column number in bytes where this location starts from the start of the line.

# File lib/prism/parse_result.rb, line 290
def start_column
  source.column(start_offset)
end

start_line() click to toggle source

The line number where this location starts.

# File lib/prism/parse_result.rb, line 273
def start_line
  source.line(start_offset)
end

start_line_slice() click to toggle source

The content of the line where this location starts before this location.

# File lib/prism/parse_result.rb, line 278
def start_line_slice
  offset = source.line_start(start_offset)
  source.slice(offset, start_offset - offset)
end

trailing_comment(comment) click to toggle source

Attach a comment to the trailing comments of this location.

# File lib/prism/parse_result.rb, line 201
def trailing_comment(comment)
  trailing_comments << comment
end

trailing_comments() click to toggle source

These are the comments that are associated with this location that exist after the end of this location.

# File lib/prism/parse_result.rb, line 196
def trailing_comments
  @trailing_comments ||= []
end