DiMaPa (Diff Match and Patch)

A modern Ruby implementation of Google's Diff Match and Patch libraries.

The Diff Match and Patch libraries offer robust algorithms to perform the operations required for synchronizing plain text.

Usage

require 'dimapa'

dmp = DiMaPa.new # or DiffMatchPatch

diff = dmp.diff_main("This is a sentence.", "This is also a sentence.")
#=> [[:equal, "This is a"], [:insert, "lso a"], [:equal, " sentence."]]

dmp.diff_cleanup_semantic(diff)
#=> nil

# diff is modified in place
diff
#=> [[:equal, "This is "], [:insert, "also "], [:equal, "a sentence."]]

patch = dmp.patch_make(diff)
#=> [#<PatchObj:0x00005608e6ac9500 @diffs=
#     [[:equal, "This is "], [:insert, "also "], [:equal, "a senten"]],
#     @length1=16,
#     @length2=21,
#     @start1=0,
#     @start2=0>]

dmp.patch_to_text(patch)
#=> "@@ -1,16 +1,21 @@\n This is \n+also \n a senten\n"

dmp.patch_apply(patch, "This is a sentence.")
#=> ["This is also a sentence.", [true]]

Installation

# RubyGem
gem install dimapa

# From source
bundle install
bundle exec rake install

Benchmarks

This project includes scripts/ mirroring those in the official project. Performance is on par with those reported for Lua and Python albeit run on a faster machine.

$ bundle exec rake speedtest
Running benchmark with plain Ruby
ruby scripts/speedtest.rb
              user     system      total        real
diff(t2,t1)  9.587209   0.013017   9.600226 (  9.601807)
diff(t1,t2)  9.750088   0.008715   9.758803 (  9.758928)

Running benchmark with JIT enabled
ruby --jit scripts/speedtest.rb
              user     system      total        real
diff(t2,t1)  5.345181   0.020641   7.082650 (  5.359839)
diff(t1,t2)  6.528630   0.028800   7.395639 (  6.566026)

Tests and Linting

bundle exec rake

Fork of kalmbach/diff_match_patch b/w/o DavidMikeSimon/diff_match_patch

Work was inspired by the reima/diff_match_patch-ruby module.