Run a subcommand a set number of times

run.rb

#!/usr/bin/env ruby

##
# Usage `run --number 5 b rspec`
#
#
##

require 'optparse'
require 'open3'
require 'shellwords'
require 'securerandom'
require 'fileutils'

##
# Run a command and send the command output to stdout/stderr
class Command
  def run(*args)
    execute_command(*args)
  end

  private

  def execute_command(*args)
    status = Open3.popen3(*args) do |_i, o, e, t|
      out = Thread.new do
        until o.eof? || o.closed?
          STDOUT.puts o.gets
        end
      end
      err = Thread.new do
        until e.eof? || o.closed?
          STDERR.puts e.gets
        end
      end
      out.join
      err.join
      t.value.to_i
    end
    status
  end
end

options = {
  count: 3,
  fail_fast: false
}

OptionParser.new do |opts|
  opts.banner = 'Usage: run -n 10 [command]'

  opts.on('--number N', Integer, 'Number of times to run') do |count|
    options[:count] = count
  end

  opts.on('--fail-fast', 'Stop if there is a failure') do
    options[:fail_fast] = true
  end
end.parse!

sub_command = Shellwords.join(ARGV.map { |word| Shellwords.escape(word) })

results = []

path = File.join('/', 'tmp', SecureRandom.uuid)

content = <<~EOF
          #!/bin/bash --login

          source ~/.bash_profile
          shopt -s expand_aliases

          #{sub_command}
          EOF

File.open(path, 'w+') { |f| f.write(content) }

FileUtils.chmod('+x', path)

begin
  options[:count].times do |index|
    STDOUT.puts "Running (#{index}) #{sub_command}"
    status = Command.new.run("/bin/bash -c '#{path}'")
    if options[:fail_fast] && status != 0
      STDERR.puts "Early Exit: Sub Command Failed #{status}"
      raise "Early Exit: Sub Command Failed #{status}"
    end
    results << status
  end
rescue StandardError => error
  STDERR.puts error.message
  exit(1)
ensure
  FileUtils.rm(path)
end