VerboseShell adds -x-like logging to FileUtils functions. Example:

require 'verbose-shell'
Vsh = VerboseShell
Vsh.system(*%W'ls -l')
Vsh.verbose = true
Vsh.system(*%W'echo Hello')
Vsh.cp('/etc/passwd', '/tmp/passwd')

This outputs:

+ echo Hello
Hello
+ cp /etc/passwd /tmp/passwd

Add this line to your application's Gemfile:

gem 'verbose-shell'

And then execute:

$ bundle

Or install it yourself as:

$ gem install verbose-shell

Set VerboseShell.verbose to true or false. The default is false, so no logging will occur until it is changed.

All FileUtils functions are supported. They may not log correctly--if you find one that doesn't log in a sane way, file a bug or (hopefully) a pull request.

In addition, the following functions are available (all will log when verbose is set):

• VerboseShell.system(*args): Similar to Kernel.system except it only accepts the multiple argument form (for safety). It is therefore never run through the shell, and shell meta characters are unsupported (so no |, &&, ||, etc.). When verbose is not set, output will be captured and stored in an exception if there is an error, or discarded if there is no error. If verbose is set, output will display immediately and not be captured (even on errors).

• VerboseShell.system_or_true(*args): Similar to the above, but will never throw exceptions.

• VerboseShell.capture(*args): A wrapper around IO.popen(). Returns the stdout of the command given. Like VerboseShell.system(), only the multiple argument form is accepted (so no shell is involved).

• which?(exe_name): Searches through ENV['PATH'] and returns the full path of exe_name if found, and nil if not found.

• install_D(source, dest): Like install -D (see INSTALL(1)).

After checking out the repo, run bin/setup to install dependencies. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Bug reports and pull requests are welcome on GitHub at https://github.com/caldwell/verbose-shell.

The gem is available as open source under the terms of the MIT License.