How can shared examples be shared across gems?

Hi,

I have shared examples in a gem…

some_gem_name/spec/some_gem_name/shared_examples.rb

…where the shared examples are contained in a module, e.g.,

module SharedExamples

shared_examples_for …

end

How can I include these shared examples in tests in a different gem
that depends on my some_gem_name, above? Maybe I can refer to the
shared examples in my dependent gem’s spec_helper?

Thanks,

Lille

On Dec 11, 2011, at 4:02 PM, Lille wrote:

shared_examples_for …

end

How does this even work? shared_examples_for is not defined in Module,
so unless you’re leaving something important out, that should raise an
error.

How can I include these shared examples in tests in a different gem
that depends on my some_gem_name, above? Maybe I can refer to the
shared examples in my dependent gem’s spec_helper?

There are two ways you can do this:

shared_examples “stuff” do
before { … }
let(:name) { value }
it “does something” do
# …
end
end

As long as this file is required somewhere (only once, please) you can
use those examples in your gem or any other gem:

describe Something do
it_behaves_like “stuff”
end

You can also define a module:

module SharedExamples
extend RSpec::Core::SharedContext
before { … }
let(:name) { value }
it “does something” do
# …
end
end

Now you can do a standard Ruby include

describe Something do
include SharedExamples
end

see
https://www.relishapp.com/rspec/rspec-core/docs/example-groups/shared-examples
see
http://rubydoc.info/github/rspec/rspec-core/master/RSpec/Core/SharedContext

HTH,
David

Thank you.

Here is what I did to conform my gem spec to the conventions suggested
at
https://www.relishapp.com/rspec/rspec-core/docs/example-groups/shared-examples

my spec/spec_helper.rb…

$LOAD_PATH.unshift(File.dirname(FILE))
$LOAD_PATH.unshift(File.join(File.dirname(FILE), ‘…’, ‘lib’))

Dir[“spec/support/**/*.rb”].each {|f| require f} # this did not

work…

require ‘rubygems’
require ‘rum_92265’
require ‘rspec’
require ‘rspec/autorun’
require ‘support/shared_examples’ # this did

now, at the top of in lib/rum_92265.rb…

require “rum_92265/version”
require File.dirname(FILE) + “/…/spec/support/shared_examples.rb”

finally, here are the top lines of the spec/support/
shared_sample.rb…

extend RSpec::Core::SharedContext

shared_examples_for “Rum92265::A3::PartB” do

Anyway, I hadn’t seen any gems with shared example groups exposed, so
this was the best I could come up with – it worked. It seems weird to
require shared_samples.rb from the lib directory, but I couldn’t see
where else – gemspec, for example? – to require it.

Lille

On Dec 13, 2011, at 6:30 PM, Lille wrote:

I moved your post to the bottom. Please read
http://idallen.com/topposting.html and please bottom post or inline post
so readers can more easily follow the thread.

shared examples in my dependent gem’s spec_helper?

before { … }
end

seehttps://www.relishapp.com/rspec/rspec-core/docs/example-groups/shared…
seehttp://rubydoc.info/github/rspec/rspec-core/master/RSpec/Core/SharedC…

HTH,
David

Thank you.

Here is what I did to conform my gem spec to the conventions suggested
at
https://www.relishapp.com/rspec/rspec-core/docs/example-groups/shared-examples

my spec/spec_helper.rb…

$LOAD_PATH.unshift(File.dirname(FILE))
$LOAD_PATH.unshift(File.join(File.dirname(FILE), ‘…’, ‘lib’))

You don’t need to modify the ^^ LOAD_PATH ^^ here - it’s already done
for you by RSpec.

Dir[“spec/support/**/*.rb”].each {|f| require f} # this did not work…

I’m assuming you’re using Ruby 1.9, which does not include “.” on the
LOAD_PATH (which is assumed by Dir[“spec/support/**/*.rb”]). Either of
these would work:

Dir["./spec/support//*.rb"].each {|f| require f}
Dir["support/
/*.rb"].each {|f| require f}

I’ll update the docs on relishapp.com accordingly.

require File.dirname(FILE) + “/…/spec/support/shared_examples.rb”
This ^^ is going to get you into trouble because Ruby doesn’t see
/path/to/x/…/spec/support/shared_examples.rb and
/path/to/spec/support/shared_examples.rb as the same path (even though
they end at the same file). This means that your users will likely end
up requiring shared_examples.rb twice, which makes bad things happen.

I’d recommend modifying and relying on the LOAD_PATH instead. More
below.

finally, here are the top lines of the spec/support/
shared_sample.rb…

extend RSpec::Core::SharedContext

shared_examples_for “Rum92265::A3::PartB” do

You don’t need both “extend RSpec::Core::SharedContext” and
“shared_examples_for”. Just one or the other.

Anyway, I hadn’t seen any gems with shared example groups exposed, so
this was the best I could come up with – it worked. It seems weird to
require shared_samples.rb from the lib directory, but I couldn’t see
where else – gemspec, for example? – to require it.

Lille

If the idea here is to expose shared_examples to users of your gem, I’d
actually store them under lib. Something like:

lib/rum_92265/spec_support.rb # requires
rum_92265/spec_support/shared_examples.rb
lib/rum_92265/spec_support/shared_examples.rb

Now you can require ‘rum_92265/spec_support’ in your own
spec/spec_helper.rb, and you can tell your users to do the same.

HTH,
David

Here is what I did to conform my gem spec to the conventions suggested
athttps://www.relishapp.com/rspec/rspec-core/docs/example-groups/shared…

my spec/spec_helper.rb…

$LOAD_PATH.unshift(File.dirname(FILE))
$LOAD_PATH.unshift(File.join(File.dirname(FILE), ‘…’, ‘lib’))

You don’t need to modify the ^^ LOAD_PATH ^^ here - it’s already done for you by
RSpec.

OK - I made this change, thanks…

finally, here are the top lines of the spec/support/
shared_sample.rb…

extend RSpec::Core::SharedContext

shared_examples_for “Rum92265::A3::PartB” do

You don’t need both “extend RSpec::Core::SharedContext” and
“shared_examples_for”. Just one or the other.

…and made this change…

If the idea here is to expose shared_examples to users of your gem, I’d actually
store them under lib. Something like:

lib/rum_92265/spec_support.rb # requires
rum_92265/spec_support/shared_examples.rb
lib/rum_92265/spec_support/shared_examples.rb

Now you can require ‘rum_92265/spec_support’ in your own spec/spec_helper.rb,
and you can tell your users to do the same.

…finally, I did this, too. These steps added up to a successful
result for me.

Thank you very much for your detailed and helpful response.

Lille