class Parser::Source::Range

A range of characters in a particular source buffer.

The range is always exclusive, i.e. a range with `begin_pos` of 3 and `end_pos` of 5 will contain the following characters:

example
   ^^

@!attribute [r] #source_buffer

@return [Parser::Diagnostic::Engine]

@!attribute [r] #begin_pos

@return [Integer] index of the first character in the range

@!attribute [r] #end_pos

@return [Integer] index of the character after the last character in the range

@api public

Attributes

begin_pos[R]
end_pos[R]
source_buffer[R]

Public Class Methods

new(source_buffer, begin_pos, end_pos) click to toggle source

@param [Buffer] #source_buffer @param [Integer] #begin_pos @param [Integer] #end_pos

# File lib/parser/source/range.rb, line 33
def initialize(source_buffer, begin_pos, end_pos)
  if end_pos < begin_pos
    raise ArgumentError, 'Parser::Source::Range: end_pos must not be less than begin_pos'
  end
  if source_buffer.nil?
    raise ArgumentError, 'Parser::Source::Range: source_buffer must not be nil'
  end

  @source_buffer       = source_buffer
  @begin_pos, @end_pos = begin_pos, end_pos

  freeze
end

Public Instance Methods

==(other) click to toggle source

Compares ranges. @return [Boolean]

# File lib/parser/source/range.rb, line 226
def ==(other)
  other.is_a?(Range) &&
    @source_buffer == other.source_buffer &&
    @begin_pos     == other.begin_pos     &&
    @end_pos       == other.end_pos
end
begin() click to toggle source

@return [Range] a zero-length range located just before the beginning

of this range.
# File lib/parser/source/range.rb, line 51
def begin
  Range.new(@source_buffer, @begin_pos, @begin_pos)
end
column() click to toggle source

@return [Integer] zero-based column number of the beginning of this range.

# File lib/parser/source/range.rb, line 88
def column
  @source_buffer.column_for_position(@begin_pos)
end
column_range() click to toggle source

@return [::Range] a range of columns spanned by this range. @raise RangeError

# File lib/parser/source/range.rb, line 110
def column_range
  if self.begin.line != self.end.line
    raise RangeError, "#{self.inspect} spans more than one line"
  end

  self.begin.column...self.end.column
end
disjoint?(other) click to toggle source

@param [Range] other @return [Boolean] `true` if this range and `other` do not overlap

# File lib/parser/source/range.rb, line 203
def disjoint?(other)
  @begin_pos >= other.end_pos || other.begin_pos >= @end_pos
end
empty?() click to toggle source

Checks if a range is empty; if it contains no characters @return [Boolean]

# File lib/parser/source/range.rb, line 218
def empty?
  @begin_pos == @end_pos
end
end() click to toggle source

@return [Range] a zero-length range located just after the end

of this range.
# File lib/parser/source/range.rb, line 59
def end
  Range.new(@source_buffer, @end_pos, @end_pos)
end
first_line()
Alias for: line
inspect() click to toggle source

@return [String] a human-readable representation of this range.

# File lib/parser/source/range.rb, line 236
def inspect
  "#<Parser::Source::Range #{@source_buffer.name} #{@begin_pos}...#{@end_pos}>"
end
intersect(other) click to toggle source

@param [Range] other @return [Range] overlapping region of this range and `other`, or `nil`

if they do not overlap
# File lib/parser/source/range.rb, line 191
def intersect(other)
  unless disjoint?(other)
    Range.new(@source_buffer,
      [@begin_pos, other.begin_pos].max,
      [@end_pos,   other.end_pos].min)
  end
end
is?(*what) click to toggle source

`is?` provides a concise way to compare the source corresponding to this range. For example, `r.source == '(' || r.source == 'begin'` is equivalent to `r.is?('(', 'begin')`.

# File lib/parser/source/range.rb, line 137
def is?(*what)
  what.include?(source)
end
join(other) click to toggle source

@param [Range] other @return [Range] smallest possible range spanning both this range and `other`.

# File lib/parser/source/range.rb, line 180
def join(other)
  Range.new(@source_buffer,
      [@begin_pos, other.begin_pos].min,
      [@end_pos,   other.end_pos].max)
end
last_column() click to toggle source

@return [Integer] zero-based column number of the end of this range.

# File lib/parser/source/range.rb, line 102
def last_column
  @source_buffer.column_for_position(@end_pos)
end
last_line() click to toggle source

@return [Integer] line number of the end of this range.

# File lib/parser/source/range.rb, line 95
def last_line
  @source_buffer.line_for_position(@end_pos)
end
length()
Alias for: size
line() click to toggle source

Line number of the beginning of this range. By default, the first line of a buffer is 1; as such, line numbers are most commonly one-based.

@see Buffer @return [Integer] line number of the beginning of this range.

# File lib/parser/source/range.rb, line 79
def line
  @source_buffer.line_for_position(@begin_pos)
end
Also aliased as: first_line
overlaps?(other) click to toggle source

@param [Range] other @return [Boolean] `true` if this range and `other` overlap

# File lib/parser/source/range.rb, line 211
def overlaps?(other)
  @begin_pos < other.end_pos && other.begin_pos < @end_pos
end
resize(new_size) click to toggle source

@param [Integer] new_size @return [Range] a range beginning at the same point as this range and length `new_size`.

# File lib/parser/source/range.rb, line 172
def resize(new_size)
  Range.new(@source_buffer, @begin_pos, @begin_pos + new_size)
end
size() click to toggle source

@return [Integer] amount of characters included in this range.

# File lib/parser/source/range.rb, line 66
def size
  @end_pos - @begin_pos
end
Also aliased as: length
source() click to toggle source

@return [String] all source code covered by this range.

# File lib/parser/source/range.rb, line 128
def source
  @source_buffer.slice(self.begin_pos...self.end_pos)
end
source_line() click to toggle source

@return [String] a line of source code containing the beginning of this range.

# File lib/parser/source/range.rb, line 121
def source_line
  @source_buffer.source_line(line)
end
to_a() click to toggle source

@return [Array(Integer)] a set of character indexes contained in this range.

# File lib/parser/source/range.rb, line 144
def to_a
  (@begin_pos...@end_pos).to_a
end
to_s() click to toggle source

Composes a GNU/Clang-style string representation of the beginning of this range.

For example, for the following range in file `foo.rb`,

def foo
    ^^^

`to_s` will return `foo.rb:1:5`. Note that the column index is one-based.

@return [String]

# File lib/parser/source/range.rb, line 162
def to_s
  line, column = @source_buffer.decompose_position(@begin_pos)

  [@source_buffer.name, line, column + 1].join(':')
end