view lib/redmine/unified_diff.rb @ 1082:997f6d7738f7 bug_531

In repo controller entry action, show the page for the file even if it's binary (so user still has access to history etc links). This makes it possible to use the entry action as the default when a file is clicked on

# Redmine - project management software
# Copyright (C) 2006-2011  Jean-Philippe Lang
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

module Redmine
  # Class used to parse unified diffs
  class UnifiedDiff < Array
    attr_reader :diff_type

    def initialize(diff, options={})
      options.assert_valid_keys(:type, :max_lines)
      diff = diff.split("\n") if diff.is_a?(String)
      @diff_type = options[:type] || 'inline'
      lines = 0
      @truncated = false
      diff_table = DiffTable.new(@diff_type)
      diff.each do |line|
        line_encoding = nil
        if line.respond_to?(:force_encoding)
          line_encoding = line.encoding
          # TODO: UTF-16 and Japanese CP932 which is imcompatible with ASCII
          #       In Japan, diffrence between file path encoding
          #       and file contents encoding is popular.
          line.force_encoding('ASCII-8BIT')
        end
        unless diff_table.add_line line
          line.force_encoding(line_encoding) if line_encoding
          self << diff_table if diff_table.length > 0
          diff_table = DiffTable.new(diff_type)
        end
        lines += 1
        if options[:max_lines] && lines > options[:max_lines]
          @truncated = true
          break
        end
      end
      self << diff_table unless diff_table.empty?
      self
    end

    def truncated?; @truncated; end
  end

  # Class that represents a file diff
  class DiffTable < Array
    attr_reader :file_name

    # Initialize with a Diff file and the type of Diff View
    # The type view must be inline or sbs (side_by_side)
    def initialize(type="inline")
      @parsing = false
      @added = 0
      @removed = 0
      @type = type
    end

    # Function for add a line of this Diff
    # Returns false when the diff ends
    def add_line(line)
      unless @parsing
        if line =~ /^(---|\+\+\+) (.*)$/
          @file_name = $2
        elsif line =~ /^@@ (\+|\-)(\d+)(,\d+)? (\+|\-)(\d+)(,\d+)? @@/
          @line_num_l = $2.to_i
          @line_num_r = $5.to_i
          @parsing = true
        end
      else
        if line =~ /^[^\+\-\s@\\]/
          @parsing = false
          return false
        elsif line =~ /^@@ (\+|\-)(\d+)(,\d+)? (\+|\-)(\d+)(,\d+)? @@/
          @line_num_l = $2.to_i
          @line_num_r = $5.to_i
        else
          parse_line(line, @type)
        end
      end
      return true
    end

    def each_line
      prev_line_left, prev_line_right = nil, nil
      each do |line|
        spacing = prev_line_left && prev_line_right && (line.nb_line_left != prev_line_left+1) && (line.nb_line_right != prev_line_right+1)
        yield spacing, line
        prev_line_left = line.nb_line_left.to_i if line.nb_line_left.to_i > 0
        prev_line_right = line.nb_line_right.to_i if line.nb_line_right.to_i > 0
      end
    end

    def inspect
      puts '### DIFF TABLE ###'
      puts "file : #{file_name}"
      self.each do |d|
        d.inspect
      end
    end

    private

    def diff_for_added_line
      if @type == 'sbs' && @removed > 0 && @added < @removed
        self[-(@removed - @added)]
      else
        diff = Diff.new
        self << diff
        diff
      end
    end

    def parse_line(line, type="inline")
      if line[0, 1] == "+"
        diff = diff_for_added_line
        diff.line_right = line[1..-1]
        diff.nb_line_right = @line_num_r
        diff.type_diff_right = 'diff_in'
        @line_num_r += 1
        @added += 1
        true
      elsif line[0, 1] == "-"
        diff = Diff.new
        diff.line_left = line[1..-1]
        diff.nb_line_left = @line_num_l
        diff.type_diff_left = 'diff_out'
        self << diff
        @line_num_l += 1
        @removed += 1
        true
      else
        write_offsets
        if line[0, 1] =~ /\s/
          diff = Diff.new
          diff.line_right = line[1..-1]
          diff.nb_line_right = @line_num_r
          diff.line_left = line[1..-1]
          diff.nb_line_left = @line_num_l
          self << diff
          @line_num_l += 1
          @line_num_r += 1
          true
        elsif line[0, 1] = "\\"
          true
        else
          false
        end
      end
    end

    def write_offsets
      if @added > 0 && @added == @removed
        @added.times do |i|
          line = self[-(1 + i)]
          removed = (@type == 'sbs') ? line : self[-(1 + @added + i)]
          offsets = offsets(removed.line_left, line.line_right)
          removed.offsets = line.offsets = offsets
        end
      end
      @added = 0
      @removed = 0
    end

    def offsets(line_left, line_right)
      if line_left.present? && line_right.present? && line_left != line_right
        max = [line_left.size, line_right.size].min
        starting = 0
        while starting < max && line_left[starting] == line_right[starting]
          starting += 1
        end
        ending = -1
        while ending >= -(max - starting) && line_left[ending] == line_right[ending]
          ending -= 1
        end
        unless starting == 0 && ending == -1
          [starting, ending]
        end
      end
    end
  end

  # A line of diff
  class Diff
    attr_accessor :nb_line_left
    attr_accessor :line_left
    attr_accessor :nb_line_right
    attr_accessor :line_right
    attr_accessor :type_diff_right
    attr_accessor :type_diff_left
    attr_accessor :offsets

    def initialize()
      self.nb_line_left = ''
      self.nb_line_right = ''
      self.line_left = ''
      self.line_right = ''
      self.type_diff_right = ''
      self.type_diff_left = ''
    end

    def type_diff
      type_diff_right == 'diff_in' ? type_diff_right : type_diff_left
    end

    def line
      type_diff_right == 'diff_in' ? line_right : line_left
    end

    def html_line_left
      line_to_html(line_left, offsets)
    end

    def html_line_right
      line_to_html(line_right, offsets)
    end

    def html_line
      line_to_html(line, offsets)
    end

    def inspect
      puts '### Start Line Diff ###'
      puts self.nb_line_left
      puts self.line_left
      puts self.nb_line_right
      puts self.line_right
    end

    private

    def line_to_html(line, offsets)
      if offsets
        s = ''
        unless offsets.first == 0
          s << CGI.escapeHTML(line[0..offsets.first-1])
        end
        s << '<span>' + CGI.escapeHTML(line[offsets.first..offsets.last]) + '</span>'
        unless offsets.last == -1
          s << CGI.escapeHTML(line[offsets.last+1..-1])
        end
        s
      else
        CGI.escapeHTML(line)
      end
    end
  end
end