This is the RSpec mono repo, it contains the core gems we think of as "rspec", they are:
-
rspec-core
provides the structure for writing executable examples of how your code should behave, and anrspec
command with tools to constrain which examples get run and tailor the output. -
rspec-expectations
lets you express expected outcomes on an object in an example. -
rspec-mocks
is a test-double framework for rspec with support for method stubs, fakes, and message expectations on generated test-doubles and real objects alike. -
rspec-support
provides shared helper functionality for the other three gems, in general you don't install this on its own.
gem install rspec # for rspec-core, rspec-expectations and rspec-mocks
gem install rspec-core # for rspec-core only
gem install rspec-expectations # for rspec-expectations only
gem install rspec-mocks # for rspec-mocks only
Want to run against the main
branch? You'll need to include the dependent
RSpec repos as well. Add the following to your Gemfile
:
%w[rspec rspec-core rspec-expectations rspec-mocks rspec-support].each do |lib|
if lib == 'rspec'
gem lib, git: "https://github.com/rspec/rspec"
else
gem lib, git: "https://github.com/rspec/rspec", glob: "#{lib}/#{lib}.gemspec"
end
end
If you install the rspec-core gem, it installs the rspec
executable,
which you'll use to run rspec. The rspec
command comes with many useful
options.
Run rspec --help
to see the complete list.
RSpec uses the words "describe" and "it" so we can express concepts like a conversation:
"Describe a calculator."
"It adds together numbers."
e.g.
# in spec/calculator_spec.rb
RSpec.describe Calculator do
describe '#add' do
it 'returns the sum of its arguments' do
expect(Calculator.new.add(1, 2)).to eq(3)
end
end
end
Run this with the rspec command, and watch it fail:
$ rspec spec/calculator_spec.rb
./spec/calculator_spec.rb:1: uninitialized constant Calculator
Address the failure by defining a skeleton of the Calculator
class:
# in lib/calculator.rb
class Calculator
def add(a, b)
end
end
Be sure to require the implementation file in the spec:
# in spec/calculator_spec.rb
# - RSpec adds ./lib to the $LOAD_PATH
require "calculator"
Now run the spec again, and watch the expectation fail:
$ rspec spec/calculator_spec.rb
F
Failures:
1) Calculator#add returns the sum of its arguments
Failure/Error: expect(Calculator.new.add(1, 2)).to eq(3)
expected: 3
got: nil
(compared using ==)
# ./spec/calculator_spec.rb:6:in `block (3 levels) in <top (required)>'
Finished in 0.00131 seconds (files took 0.10968 seconds to load)
1 example, 1 failure
Failed examples:
rspec ./spec/calculator_spec.rb:5 # Calculator#add returns the sum of its arguments
Implement the simplest solution, by changing the definition of Calculator#add
to:
def add(a, b)
a + b
end
Now run the spec again, and watch it pass:
$ rspec spec/calculator_spec.rb
.
Finished in 0.000315 seconds
1 example, 0 failures
Use the documentation
formatter to see the resulting spec:
$ rspec spec/calculator_spec.rb --format doc
Calculator
#add
returns the sum of its arguments
Finished in 0.000379 seconds
1 example, 0 failures
Once you've set up the environment, you'll need to cd into the working directory of whichever repo you want to work in. From there you can run the specs and cucumber features, and make patches.
NOTE: You do not need to use rspec-dev to work on a specific RSpec repo. You can treat each RSpec repo as an independent project.