guidiff.rb

#!/usr/bin/env ruby

# == Synopsis
#
# guidiff.rb [--no-compress] [file1] [file2] [...]
#
# == Usage
#
# -h, --help:
#    show this help
#
# --no-compress, -n
#    disable output compression (automatically disabled when using vimdiff)
#
# --vimdiff, -v
#    use vimdiff
#
# --filemerge, -f
#    use FileMerge.app (via opendiff)
#
# file1, file2, ...
#    list of files to operate on. if blank, assumes current directory is to be
#    diffed. directories can also be explicit arguments.

require 'tempfile'
require 'getoptlong'
require 'rdoc/usage'

VIMDIFF = "vimdiff"
OPENDIFF = "opendiff"

class GuiDiff

    def initialize
        @files = nil
        @compress = true
        @diff_tool = "opendiff"
    end

    def opts
        opts = GetoptLong.new(
              [ '--help', '-h', GetoptLong::NO_ARGUMENT ],
              [ '--no-compress', '-n', GetoptLong::NO_ARGUMENT ],
              [ '--vimdiff', '-v', GetoptLong::NO_ARGUMENT ],
              [ '--filemerge', '-f', GetoptLong::NO_ARGUMENT ]
            )

        opts.each do |opt, arg|
            case opt
            when '--help'
                RDoc::usage
            when '--no-compress'
                @compress = false
            when '--vimdiff'
                @diff_tool = VIMDIFF
            when '--filemerge'
                @diff_tool = OPENDIFF
            end
        end

        if @diff_tool == VIMDIFF then
            # disable this feature when using vimdiff
            @compress = false
        end

        @paths = ARGV
        if @paths.empty? then
            @paths = [ File.expand_path(".") ]
        else
            @paths.map! { |p| File.expand_path(p) }
        end

    end

    def main

        self.opts()

        def do_diff(f)
            diff = `svn diff #{f}`
        end

        def do_header(f, o)
            o.puts "Index: #{f}"
            o.puts "==================================================================="
        end

        temp1 = Tempfile.new("guidiff-").path
        temp2 = Tempfile.new("guidiff-").path

        out1 = File.open(temp1, "w")
        out2 = File.open(temp2, "w")

        i = 0
        modified_files = []
        @paths.each do |p|
            mp = `svn status #{p}`.split("\n").reject{ |s| s =~ /^\?/ }.map { |s| s =~ /^.\s+(.*?)$/; $1 }
            modified_files += mp
        end
        modified_files.each do |f|

            i += 1
            if i > 1 then
                # add an extra blank line
                out1.write "\n"
                out2.write "\n"
            end

            if modified_files.size > 1 then
                do_header(f, out1)
                do_header(f, out2)
            end

            # include compressed output?
            if @compress then
                do_diff(f, out1)
            else
                out1.write `svn cat #{f}`
            end

            # current [working copy] file
            out2.write `cat #{f}`

        end

        out1.close
        out2.close
        
        puts temp1
        puts temp2

        system("#{@diff_tool} #{temp1} #{temp2}")

        

    end

end

GuiDiff.new.main()