rspec-shell_command
The RSpec extention for writing a behavior of external command.
Installation
Add this line to your application's Gemfile:
gem 'rspec-shell_command'
And then execute:
$ bundle
Or install it yourself as:
$ gem install rspec-shell_command
Usage
require 'rspec/shell_command'
describe '`echo hello; echo goodbye >&2`' do
# Enables DSL
include RSpec::ShellCommand::DSL
# Check whether success or fail
it 'successes' do
expect(`echo hello; echo goodbye >&2`).to success
end
# Check the status code
it 'exit with status code 0' do
expect(`echo hello; echo goodbye >&2`).to exit_with(0)
end
# Check standard output
# (The output matcher behaves like the builtin output)
it 'output "hello\n" to stdout' do
expect(`echo hello; echo goodbye >&2`).to output("hello\n").to_stdout
end
# Check standard error
it 'output a some string to stderr' do
expect(`echo hello; echo goodbye >&2`).to output.to_stderr
end
end
# Composing matcher is supported!
describe '`echo hello; echo goodbye >&2; exit 2`' do
include RSpec::ShellCommand::DSL
subject { `echo hello; echo goodbye >&2; exit 2` }
# Check the status code using a composing matcher
it { is_expected.to exit_with(a_value_between(1, 3)) }
# Check standard output using a Regexp
it { is_expected.to output(/ell/).to_stdout }
# Check standard error using a composing matcher
it { is_expected.to output(a_string_starting_with('good')).to_stderr }
end
NOTE: When including RSpec::ShellCommand::DSL, a backquote operator returns a wrapper object of given command, instead of the standard output.
If you need to use RSpec::ShellCommand::DSL at all examples, you can write as bellow at your spec/spec_helper.rb:
require 'rspec/shell_command'
RSpec.configure do |c|
c.include RSpec::ShellCommand::DSL
end