class Pact::Matchers::Differ

Public Class Methods

new(color = false) click to toggle source
# File lib/pact/matchers/differ.rb, line 14
def initialize(color = false)
  @color = color
end

Public Instance Methods

diff_as_object(actual, expected) click to toggle source
# File lib/pact/matchers/differ.rb, line 66
def diff_as_object(actual, expected)
  actual_as_string = object_to_string(actual)
  expected_as_string = object_to_string(expected)
  if diff = diff_as_string(actual_as_string, expected_as_string)
    color_diff diff
  end
end
diff_as_string(input_data_new, input_data_old) click to toggle source

This is snagged from diff/lcs/ldiff.rb (which is a commandline tool)

# File lib/pact/matchers/differ.rb, line 19
def diff_as_string(input_data_new, input_data_old)
  output = matching_encoding("", input_data_old)
  data_old = input_data_old.split(matching_encoding("\n", input_data_old)).map! { |e| e.chomp }
  data_new = input_data_new.split(matching_encoding("\n", input_data_new)).map! { |e| e.chomp }
  diffs = Diff::LCS.diff(data_old, data_new)
  return output if diffs.empty?
  oldhunk = hunk = nil
  file_length_difference = 0
  diffs.each do |piece|
    begin
      hunk = Diff::LCS::Hunk.new(
        data_old, data_new, piece, context_lines, file_length_difference
      )
      file_length_difference = hunk.file_length_difference
      next unless oldhunk
      # Hunks may overlap, which is why we need to be careful when our
      # diff includes lines of context. Otherwise, we might print
      # redundant lines.
      if (context_lines > 0) and hunk.overlaps?(oldhunk)
        if hunk.respond_to?(:merge)
          # diff-lcs 1.2.x
          hunk.merge(oldhunk)
        else
          # diff-lcs 1.1.3
          hunk.unshift(oldhunk)
        end
      else
        output << matching_encoding(oldhunk.diff(format).to_s, output)
      end
    ensure
      oldhunk = hunk
      output << matching_encoding("\n", output)
    end
  end
  #Handle the last remaining hunk
  output << matching_encoding(oldhunk.diff(format).to_s, output)
  output << matching_encoding("\n", output)
  color_diff output
rescue Encoding::CompatibilityError
  if input_data_new.encoding != input_data_old.encoding
    "Could not produce a diff because the encoding of the actual string (#{input_data_old.encoding}) "+
    "differs from the encoding of the expected string (#{input_data_new.encoding})"
  else
    "Could not produce a diff because of the encoding of the string (#{input_data_old.encoding})"
  end
end
green(text) click to toggle source
# File lib/pact/matchers/differ.rb, line 79
def green(text)
  return text unless @color
  color(text, 32)
end
red(text) click to toggle source
# File lib/pact/matchers/differ.rb, line 74
def red(text)
  return text unless @color
  color(text, 31)
end

Protected Instance Methods

blue(text) click to toggle source
# File lib/pact/matchers/differ.rb, line 99
def blue(text)
  color(text, 34)
end
color(text, color_code) click to toggle source
# File lib/pact/matchers/differ.rb, line 94
def color(text, color_code)
  "\e[#{color_code}m#{text}\e[0m"
end
color_diff(diff) click to toggle source
# File lib/pact/matchers/differ.rb, line 103
def color_diff(diff)
  return diff unless @color

  diff.lines.map { |line|
    case line[0].chr
    when "+"
      green line
    when "-"
      red line
    when "@"
      line[1].chr == "@" ? blue(line) : line
    else
      line
    end
  }.join
end
context_lines() click to toggle source
# File lib/pact/matchers/differ.rb, line 90
def context_lines
  3
end
format() click to toggle source
# File lib/pact/matchers/differ.rb, line 86
def format
  :unified
end
matching_encoding(string, source) click to toggle source
# File lib/pact/matchers/differ.rb, line 141
def matching_encoding(string, source)
  string.encode(source.encoding)
end
object_to_string(object) click to toggle source
# File lib/pact/matchers/differ.rb, line 120
def object_to_string(object)
  case object
  when Hash
    object.keys.sort_by { |k| k.to_s }.map do |key|
      pp_key   = PP.singleline_pp(key, "")
      pp_value = PP.singleline_pp(object[key], "")

      # on 1.9.3 PP seems to minimise to US-ASCII, ensure we're matching source encoding
      #
      # note, PP is used to ensure the ordering of the internal values of key/value e.g.
      # <# a: b: c:> not <# c: a: b:>
      matching_encoding("#{pp_key} => #{pp_value}", key.to_s)
    end.join(",\n")
  when String
    object =~ /\n/ ? object : object.inspect
  else
    PP.pp(object,"")
  end
end