module ParallelTests::Tasks

def check_for_pending_migrations 

def check_for_pending_migrations
  ["db:abort_if_pending_migrations", "app:db:abort_if_pending_migrations"].each do |abort_migrations|
    if Rake::Task.task_defined?(abort_migrations)
      Rake::Task[abort_migrations].invoke
      break
    end
  end
end

def parse_args(args)

parallel:spec[:count, :pattern, :options] 
def parse_args(args)
  # order as given by user
  args = [args[:count], args[:pattern], args[:options]]
  # count given or empty ?
  # parallel:spec[2,models,options]
  # parallel:spec[,models,options]
  count = args.shift if args.first.to_s =~ /^\d*$/
  num_processes = count.to_i unless count.to_s.empty?
  pattern = args.shift
  options = args.shift
  [num_processes, pattern.to_s, options.to_s]
end

def purge_before_load 

def purge_before_load
  "db:test:purge" if Gem::Version.new(Rails.version) > Gem::Version.new('4.2.0')
end

def rails_env 

def rails_env
  ENV['RAILS_ENV'] || 'test'
end

def run_in_parallel(cmd, options={}) 

def run_in_parallel(cmd, options={})
  count = " -n #{options[:count]}" unless options[:count].to_s.empty?
  executable = File.expand_path("../../../bin/parallel_test", __FILE__)
  command = "#{Shellwords.escape executable} --exec '#{cmd}'#{count}#{' --non-parallel' if options[:non_parallel]}"
  abort unless system(command)
end

def suppress_output(command, ignore_regex)

- simple system "set -o pipefail" returns nil even though set -o pipefail exists with 0
- do not use ' since run_in_parallel uses them to quote stuff
- defining a new rake task like silence_schema would force users to load parallel_tests in test env
- pipefail is not supported in (zsh)
- pipefail makes pipe fail with exitstatus of first failed command
- sed changes 1 exitstatus to 0
- grep changes 0 exitstatus to 1 if nothing matches
- sed does not support | without -r

normally I'd not do this, but it has been lots of fun and a great learning experience :)
removing certain lines from the output without changing the exit-status
this is a crazy-complex solution for a very simple problem: 
def suppress_output(command, ignore_regex)
  activate_pipefail = "set -o pipefail"
  remove_ignored_lines = %Q{(grep -v "#{ignore_regex}" || test 1)}
  if File.executable?('/bin/bash') && system('/bin/bash', '-c', "#{activate_pipefail} 2>/dev/null && test 1")
    # We need to shell escape single quotes (' becomes '"'"') because
    # run_in_parallel wraps command in single quotes
    %Q{/bin/bash -c '"'"'#{activate_pipefail} && (#{command}) | #{remove_ignored_lines}'"'"'}
  else
    command
  end
end

def suppress_schema_load_output(command) 

def suppress_schema_load_output(command)
  ParallelTests::Tasks.suppress_output(command, "^   ->\\|^-- ")
end