Script to print out the merge status of local branches with respect to an 'upstream' branch (by default, 'master'). For each local branch, it prints out the number and one-line summaries of commits that have not been merged. Run with the -m argument to print out just the merge status of each branch. The script looks at the diff introduced by com…

show-merge-status.rb

#!/usr/bin/env ruby

require 'optparse.rb'

upstream_branch = "master"
branch_names = []
show_merge_status = false

OptionParser.new do |parser|
  parser.banner = <<END
#{$0} [options]

List commits in each branch that are not merged into an upstream
branch (by default, 'master').

END

	parser.on('-u', '--upstream [name]', "Branch to compare against.  Defaults to 'master'") do |branch|
		upstream_branch = branch
	end
	parser.on('-b','--branches [names]', 'Comma-separated list of branches to compare against the upstream branch.  Defaults to all local branches') do |branches|
		branch_names = branches.split(',')
	end
	parser.on('-m','--merged', 'Print only the merge status of each branch with respect to the upstream branch') do
		show_merge_status = true
	end
end.parse!

def find_unmerged_commits(upstream_branch, head_branch)
	commits = `git cherry #{upstream_branch} #{head_branch}`.each_line.select do |cherry_line|
		cherry_line.start_with? '+'
	end
	commits.map! do |commit|
		commit.strip.match(/[0-9a-f]+/)[0]
	end

	return commits
end

def print_unmerged_commits(commits, upstream_branch, head_branch)
	if commits.empty?
		return
	end

	puts "Commits in #{head_branch} not merged into #{upstream_branch} (#{commits.length}):"
	commits.each do |id|
		commit_info = `git log -n 1 --oneline #{id}`.strip
		puts "  #{commit_info}"
	end
	puts ""
end

if branch_names.empty?
	`git branch`.each_line do |branch|
		branch_names << branch.gsub(/^[ \*]+/,'').strip
	end
end
		
branch_names.each do |branch_name|
	unmerged_commits = find_unmerged_commits(upstream_branch, branch_name)
	if show_merge_status
		if unmerged_commits.empty?
			puts "#{branch_name} is merged"
		else
			puts "#{branch_name} is not merged (#{unmerged_commits.length} commits not in #{upstream_branch})"
		end
	else
		print_unmerged_commits unmerged_commits, upstream_branch, branch_name
	end
end