RSpec::Its
RSpec::Its provides the its
method as a short-hand to specify the expected value of an attribute.
Installation
Add this line to your application's Gemfile:
gem 'rspec-its'
And then execute:
$ bundle
Or install it yourself as:
$ gem install rspec-its
And require it as:
require 'rspec/its'
Usage
Use the its
method to generate a nested example group with a single example that specifies the expected value
of an attribute of the subject using is_expected
. The its
method can also specify the block expectations of
an attribute of the subject using will
or will_not
.
its
accepts a symbol or a string, and a block representing the example.
its(:size) { is_expected.to eq(1) }
its("length") { is_expected.to eq(1) }
You can use a string with dots to specify a nested attribute (i.e. an attribute of the attribute of the subject).
its("phone_numbers.size") { is_expected.to_not eq(0) }
The following should-style method is also available:
its(:size) { should eq(1) }
as is an alias of is_expected
for pluralized use:
its(:keys) { are_expected.to eq([:key1, :key2]) }
The following block expect-style method is also available:
its(:size) { will_not raise_error }
as is this alias for pluralized use:
its(:keys) { will raise_error(NoMethodError) }
When the subject implements the []
operator, you can pass in an array with a single key to
refer to the value returned by that operator when passed that key as an argument.
its([:key]) { is_expected.to eq(value) }
For hashes, multiple keys within the array will result in successive accesses into the hash. For example:
subject { {key1: {key2: 3} } }
its([:key1, :key2]) { is_expected.to eq(3) }
For other objects, multiple keys within the array will be passed as separate arguments in a single method call to [], as in:
subject { Matrix[ [:a, :b], [:c, :d] ] }
its([1,1]) { is_expected.to eq(:d) }
Metadata arguments are supported.
its(:size, focus: true) { is_expected.to eq(1) }
Contributing
- Fork it
- Create your feature branch (
git checkout -b my-new-feature
) - Commit your changes (
git commit -am 'Add some feature'
) - Push to the branch (
git push origin my-new-feature
) - Create new Pull Request