Contents

# This class provides the ability to define a range using numbers or regular expressions
# and when provided with an array, will return a normal ruby Range object based on the matching
# elements in the array. NOTE this class is has the same attributes as Range and is identical
# when serialized (except for the class declaration obviously), but it is NOT a substitute for
# Range (only a facade).
class RegexpRange
  class PatternMatchError < StandardError
  end

  attr_reader :begin, :end, :excl

  def initialize(range_start, range_end, exclusive = false)
    @begin = range_start
    @end = range_end
    @excl = exclusive
  end

  def to_range(lines)
    start_line_number = @begin
    if start_line_number.is_a?(Regexp)
      lines.each_with_index do |line, i|
        if line.match(start_line_number)
          start_line_number = i
          break
        end
      end

      if start_line_number.is_a?(Regexp)
        fail PatternMatchError, "begin pattern #{start_line_number.inspect} not found"
      end
    end

    end_line_number = @end
    if end_line_number.is_a?(Regexp)
      start_scan_line = start_line_number + 1
      lines[start_scan_line..-1].each_with_index do |line, i|
        # puts "##{start_scan_line + i}: #{line}"
        if line.match(end_line_number)
          end_line_number = start_scan_line + i
          break
        end
      end
      if end_line_number.is_a?(Regexp)
        fail PatternMatchError,
             "end pattern #{end_line_number.inspect} not found on or after line #{start_scan_line}"
      end
    end

    Range.new(start_line_number, end_line_number, @excl)
  end

  # `other` is equal to self if it is a RegexpRange with the same state.
  def ==(other)
    other.is_a?(RegexpRange) && other.state == state
  end
  alias_method :eql?, :==

  protected

  # Used by other RegexpRange objects, as well as Hashes, during equality checks:
  def state
    [@begin, @end, @excl]
  end
  delegate :hash, :to => :state # Used for Hash key lookup
end

Version data entries

41 entries across 41 versions & 1 rubygems

Version	Path
ndr_support-3.1.1	lib/ndr_support/regexp_range.rb