Dumping composition exclusions into yml

composition_exclusions.rb

require 'open-uri'
require 'fileutils'
require 'yaml'

PROPS_URL = "http://www.unicode.org/Public/6.1.0/ucd/DerivedNormalizationProps.txt"
OUTPUT_FILE = "/tmp/cldr/composition_exclusions.yml"
EXPECTED_TOTAL_POINTS =  1120

data = open(PROPS_URL).read
start_pos = data.index("# Derived Property: Full_Composition_Exclusion")
end_pos = data.index(/^#\s=*$/, start_pos)
data = data[start_pos..end_pos].split("\n")
result = []

data.each do |line|
  unless line =~ /^#/ || line.strip.size == 0
    start, finish = line.match(/([0-9A-F]{4,6})\.?\.?([0-9A-F]{4,6})?/).captures.map { |code_point| code_point ? code_point.to_s.to_i(16) : nil }
    finish = start unless finish
    result << (start..finish)
  end
end

count = result.inject(0) { |sum, range| sum + range.count }
unless count == TOTAL_POINTS
  raise "Unexpected number of composition exclusions! Got #{count}, expected #{EXPECTED_TOTAL_POINTS}"
end

FileUtils.mkdir_p(File.dirname(OUTPUT_FILE))
File.open(OUTPUT_FILE, "w+") do |f|
  f.write(YAML::dump(result))
end