Skip to content
Automatically save screen shots when a Capybara scenario fails
Ruby
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Failed to load latest commit information.
lib
spec
.gitignore
.rspec
CHANGELOG.md
Gemfile
LICENSE
README.md
Rakefile
capybara-screenshot.gemspec

README.md

capybara-screenshot gem

Using this gem, whenever a Capybara test in Cucumber, Rspec or Minitest fails, the HTML for the failed page and a screenshot (when using capybara-webkit, Selenium or poltergeist) is saved into $APPLICATION_ROOT/tmp/capybara.

This is a huge help when trying to diagnose a problem in your failing steps as you can view the source code and potentially how the page looked at the time of the failure.

Usage

gem install capybara-screenshot

or update your Gemfile to include capybara-screenshot at the bottom (order respected as of Bundler 0.10):

gem 'capybara-screenshot', :group => :test

If you require more control, you can generate the screenshot on demand rather than on failure. This is useful if the failure occurs at a point where the screen shot is not as useful for debugging a rendering problem. This can be more useful if you disable the auto-generate on failure feature with the following config

Capybara::Screenshot.autosave_on_failure = false

Anywhere the Capybara DSL methods (visit, click etc.) are available so too will are the screenshot methods.

screen_shot_and_save_page

Or for screenshot only, which will automatically open the image.

screen_shot_and_open_image

These are just calls on the main library methods.

Capybara::Screenshot.screen_shot_and_save_page

Capybara::Screenshot.screen_shot_and_open_image

Driver configuration

The gem supports the default rendering method for Capybara to generate the screenshot, which is:

page.driver.render(path)

There are also some specific driver configurations for Selenium, Webkit, and Poltergeist. See https://github.com/mattheworiordan/capybara-screenshot/blob/master/lib/capybara-screenshot.rb. The Rack::Test driver, Rails' default, does not allow rendering, so it has a driver definition as a noop.

If a driver is not found the default rendering will be used. If this doesn't work with your driver, then you can add another driver configuration like so

# The driver name should match the Capybara driver config name.
Capybara::Screenshot.register_driver(:exotic_browser_driver) do |driver, path|
  driver.super_dooper_render(path)
end

Custom screenshot filename

If you want to control the screenshot filename for a specific test libarary, to inject the test name into it for example, you can override how the basename is generated for the file like so

Capybara::Screenshot.register_filename_prefix_formatter(:rspec) do |example|
    "screenshot-#{example.description.gsub(' ', '-')}"
  end
end

Example application

A simple Rails 3.1 example application has been set up at https://github.com/mattheworiordan/capybara-screenshot-test-rails-3.1 Git clone the app, and then run Cucumber rake cucumber, RSpec rspec spec/**/*_spec.rb and Minitest rake test and expect intentional failures. Now check the $APPLICATION_ROOT/tmp/capybara folder for the automatic screen shots generated from failed tests.

Common problems

If you find that screen shots are not automatically being generated, then it's possible the capybara-screenshot gem is loading before your testing framework is loading, and thus unable to determine which framework to hook into. Make sure you include capybara-screenshot gem last in your Gemfile (order is respected by Bundler as of 0.10). Alternatively, manually require capybara-screenshot using one of the following based on your framework:

require 'capybara-screenshot/cucumber' # For Cucumber support
require 'capybara-screenshot/rspec' # For RSpec support
require 'capybara-screenshot/minitest' # For MiniSpec support

Raise an issue on the Capybara-Screenshot issue tracker if you are still having problems.

Repository

Please fork, submit patches or feedback at https://github.com/mattheworiordan/capybara-screenshot

The gem details on RubyGems.org can be found at https://rubygems.org/gems/capybara-screenshot

About

This gem was written by Matthew O'Riordan

License

Copyright © 2012 Matthew O'Riordan, inc. It is free software, and may be redistributed under the terms specified in the LICENSE file.

Something went wrong with that request. Please try again.