free_mutant/lib/mutant/diff.rb
Markus Schirp a19f3b1691 Nuke UTF-8 encoding headers
* I do not use 1.9.3
* Also keeping them in each file increases mental overhead (true it *can* be autoamted)
* None of the files encodes NON ASCII chars.
* I do not expect it makes any difference, since nobody programmatically
  will consume strings generated by mutant under the assumption they are UTF-8 encoded.
* 1.9.3 Users have to deal with the encoding fuckup under ruby anyways.
2014-06-09 15:37:48 +00:00

110 lines
1.9 KiB
Ruby

module Mutant
# Class to create diffs from source code
class Diff
include Adamantium::Flat, Concord.new(:old, :new)
# Return source diff
#
# @return [String]
# if there is exactly one diff
#
# @return [nil]
# otherwise
#
# @api private
#
def diff
return unless diffs.length.equal?(1)
::Diff::LCS::Hunk.new(old, new, diffs.first, max_length, 0)
.diff(:unified) << "\n"
end
memoize :diff
# Return colorized source diff
#
# @return [String]
# if there is a diff
#
# @return [nil]
# otherwise
#
# @api private
#
def colorized_diff
return unless diff
diff.lines.map do |line|
self.class.colorize_line(line)
end.join
end
memoize :colorized_diff
# Return new object
#
# @param [String] old
# @param [String] new
#
# @return [Diff]
#
# @api private
#
def self.build(old, new)
new(lines(old), lines(new))
end
# Break up source into lines
#
# @param [String] source
#
# @return [Array<String>]
#
# @api private
#
def self.lines(source)
source.lines.map { |line| line.chomp }
end
private_class_method :lines
private
# Return diffs
#
# @return [Array<Array>]
#
# @api private
#
def diffs
::Diff::LCS.diff(old, new)
end
memoize :diffs
# Return max length
#
# @return [Fixnum]
#
# @api private
#
def max_length
[old, new].map(&:length).max
end
# Return colorized diff line
#
# @param [String] line
#
# @return [String]
#
# @api private
#
def self.colorize_line(line)
case line[0]
when '+'
Color::GREEN
when '-'
Color::RED
else
Color::NONE
end.format(line)
end
end # Diff
end # Mutant