git-fast-log.rb

# An old experiment, it's marginally faster for big repos
# git-fast-log <branch> <path>

branch    = ARGV[0] || "master"
dir       = ARGV[1] || "."
dir      += "/"     if dir[dir.size - 1].chr != '/'
tree      = `git-ls-tree #{branch} #{dir}`.split("\n").map { |l| l.split("\t").last }
diff_rev  = "git-rev-list --max-count=#{tree.size * 2} #{branch} #{dir}"
diff_tree = "git-diff-tree --stdin --numstat -v --pretty=oneline #{dir}"
commits   = {}

`#{diff_rev} | #{diff_tree}`.split("\n").each do |line|
  if line !~ /\t/
    @commit = line.split(' ').first
    next
  end
  path = line.split("\t").last
  key  = tree.detect { |file| path =~ /^#{file}/ }
  commits[key] ||= @commit if key
end

commits.each do |file, commit|
  commits[file] = `git-show #{commit}`
end

puts "#{commits.size} out of #{tree.size} found"

(tree - commits.keys).each do |file|
  commits[file] = `git-log --max-count=1 #{branch} #{file}`
end