cmd.txt

$ turn exec-testing.rb
Loaded suite 
TestCases
    test: #{CLIENT} "*?{}[]"                                              PASS
    test: #{CLIENT} "something ; echo anything"                           PASS
    test: #{CLIENT} "something with quotes"                               PASS
    test: #{CLIENT} "something | cat"                                     PASS
    test: #{CLIENT} $PWD $USER "$HOME $SHELL"                             PASS
    test: #{CLIENT} singlearg                                             PASS
    test: #{CLIENT} something *                                           PASS
    test: #{CLIENT} two args                                              PASS
    test: should spawn shell: #{CLIENT} && echo something                 PASS
    test: should spawn shell: cd /tmp && #{CLIENT} something              PASS
    test: should spawn shell: cd /tmp ; #{CLIENT} something               PASS
==============================================================================
  pass: 11,  fail: 0,  error: 0
  total: 11 tests with 11 assertions in 4.851785 seconds
==============================================================================

exec-testing.rb

#!/usr/bin/env ruby

if ARGV[0] == 'client'
  puts "#{$$}\nARGV: #{ARGV.inspect}"
  exit
else
  RUBY_BIN = File.join(RbConfig::CONFIG["bindir"], RbConfig::CONFIG["ruby_install_name"])
  CLIENT   = "#{RUBY_BIN} #{File.expand_path(__FILE__)} client"

  require 'test/unit'

  class TestCases < Test::Unit::TestCase
    def self.exec_testcase(command, options = {})
      should_spawn_shell = !!options[:should_spawn_shell]

      command_name = command.gsub(CLIENT, '#{CLIENT}')
      command_name = "should spawn shell: #{command_name}" if should_spawn_shell

      define_method('test: ' + command_name) do
        pids_matched, description = execute_client(command)
        spawned_shell             = !pids_matched

        assert spawned_shell == should_spawn_shell, description
      end
    end

    exec_testcase %{#{CLIENT} singlearg}
    exec_testcase %{#{CLIENT} two args}
    exec_testcase %{#{CLIENT} "something with quotes"}
    exec_testcase %{#{CLIENT} "something | cat"}
    exec_testcase %{#{CLIENT} "something ; echo anything"}
    exec_testcase %{#{CLIENT} something *}
    exec_testcase %{#{CLIENT} $PWD $USER "$HOME $SHELL"}
    exec_testcase %{#{CLIENT} "*?{}[]"}
    exec_testcase %{cd /tmp && #{CLIENT} something}, :should_spawn_shell => true
    exec_testcase %{#{CLIENT} && echo something},    :should_spawn_shell => true
    exec_testcase %{cd /tmp ; #{CLIENT} something},  :should_spawn_shell => true

    def execute_client(command)
      rd, wr = IO.pipe

      pid = fork do
        rd.close
        $stdout.reopen(wr)
        exec command
      end
      wr.close

      child_out             = rd.read
      child_pid, child_argv = child_out.split(/\n/)

      [ pid.to_s == child_pid, child_argv ]
    end
  end
end