FAILING GRACEFULLY
with Selenium and T.D.D.

FAILURE

IT’S A WAY OF LIFE

OBVIOUS
FAILURE

PREDICTABLE

SURPRISE

GRACEFUL

HOW TO COPE?

DENY IT

JUST BE VAGUE

GO ON THE OFFENSIVE

STALL FOR TIME

Better strategies? maybe just ....
CLEARER INSTRUCTIONS!

FAILURE IS NATURAL.

Good, even.

Good, even.
(fail)
(win)

AS PROGRAMMERS
we fail all the time.

The only way to fail less is to
ANTICIPATE FAILURE

The only way to fail less is to
ANTICIPATE FAILURE
and then
DON’T MAKE THE SAME
MISTAKE AGAIN
:)

THINGS HAPPEN.

BUT THEN ...

AND THEN ...

AND, WELL ...

TESTING CAN HELP.

HUMAN Q.A. TESTING
is the ideal.
(Too bad humans are so much better at other things and
need to eat and sleep and stuff ... )

SELENIUM IS
A tool for helping to automate testing.

ACTUALLY...
There are many kinds of
automated tests
http://www.flickr.com/photos/60648084@N00/1360619915/

UNIT TESTS
* For individual functions
* The cutest test.
http://www.flickr.com/photos/donsolo/2900765675/in/set-72157594163175020/

INTEGRATION TESTS
* For groups of related
functionality
* More relevant and
(almost) fun to write
http://www.flickr.com/photos/donsolo/399501571/in/set-72157594163175020/

ACCEPTANCE TESTS
* Highest level
testing.
* Basically user
stories.
* “Accepted” as in
“get fired if they
don’t work”
http://www.flickr.com/photos/donsolo

don’t get confused:
REGRESSION TESTING
(Is part of all of these, not another style)

So, let’s back up a sec.
Let me tell you a story about ...
UNIT TESTING IN RUBY
http://www.flickr.com/photos/21734563@N04/2198268918/

ASSERT

svn ci -m “math library passes
unit tests!!”

Integration testing is super cool

You can really smell the relevance.
(seriously)

HOORAY FOR USER STORIES!
Strive to pass good user-centered tests.
http://www.lukeredpath.co.uk/blog/developing-a-rails-model-using-bdd-and-rspec-part-1.html

B.D.D. = BEHAVIOR DRIVEN
DEVELOPMENT
in rspec

(which uh, actually runs)

WAIT: IT’S IMPORTANT HOW YOU DO IT!!

http://atlalt.net/screwturn/MTG-2008-07-23%20Pub%20Night.ashx

http://blog.briandicroce.com/2008/03/14/three-index-cards-to-easily-remember-the-essence-of-test-driven-development/

RIGHT.
SO, ANYWAY ...
BACK TO THIS
SELENIUM THING

SELENIUM IS INCREDIBLY...

WEIRD

why:
It’s a Firefox plugin for testing.
Turns your actions into test code.
Let’s you edit test code in the browser.
Let’s you export to lots of languages.

FUN

why:
It’s a Firefox plugin for testing.
Turns your actions into test code.
Let’s you edit test code in the browser.
Let’s you export to lots of languages.

POWERFUL

why:
It’s a Firefox plugin for testing.
Turns your actions into test code.
Let’s you edit test code in the browser.
Let’s you export to lots of languages.

FIRE-FOXY AND SIMPLE
Start here: http://seleniumhq.org/

(then go here)
HTTP://SELENIUMHQ.ORG/DOCS/

no forget about that
LETS JUST WRITE A TEST
ALREADY!

Now: Record and Playback
• Intelligent field selection will use IDs, names, or
XPath as needed
• Autocomplete for all common Selenium
commands
• Walk through tests
• Debug and set breakpoints
• Save tests as HTML, Ruby scripts, or any other
format
Totally takes 5 seconds, man

Watch this video:

GO RED

(WRITE MORE CODE)

THEN GO GREEN

SPEAK SELENESE
open
opens a page using a URL.
click/clickAndWait
performs a click operation, and
optionally waits for a new page to
load.
verifyTitle/assertTitle
verifies an expected page title.
verifyTextPresent
verifies expected text is
somewhere on the page.

VERIFY PAGE ELEMENTS
is ...
1. an element is present somewhere on the page?
2. specific text is somewhere on the page?
3. specific text is at a specific location on the page?

GOTCHAS
• clickAndWait is usually
required
• type usually requires you
to click somewhere else first
• it’s slow
• brittle if the UI is changing
rapidly

HARD PART’S JUST FINDING IT
Good thing you have so many options ...
• find elements by name
• find them by id if they have it
• or with CSS selectors if you understand the cascade
• Xpath is like a buzzsaw (a little more expensive)
• link text as a last resort (since it changes often)

Now,
SELENIUM IDE
is not the same as
SELENIUM RC

IDE and RC play great together!

RC Remote Control, that is.
• Runtests in multiple
browsers.
• Runthem remotely (on a
dedicated server)
• Runthem whenever you
check in code!

exported test to c#

exported test in java

exported test to ruby

Selenium-RC leverages the full power of
programming languages, creating tests that
can do things like
• read and write external files,
• make queries to a database,
• send emails with test reports
• practically
anything else a user can do
with a normal application ...

RC can where IDE can’t
• condition statements
• iteration
• logging and reporting of test results
• error handling, particularly unexpected errors
• database testing
• test case grouping
• re-execution of failed tests
• test case dependency
• capture screenshots on test failures

WAIT, WHAT ABOUT TEST-
DRIVEN DEVELOPMENT?
If you click around the app to build a test,
that can’t be testing before development.

RIGHT.
You actually should write them beforehand, by hand, just like
you would unit tests. It’s not so scary.
• NUnit for C#
• Junit for Java
• Selenium gem for Ruby

PUT IT ALL TOGETHER

Put it on your SVN server
trigger it with SVN hooks

Continuous Integration
with Selenium and Criuse Control

WHAT IT MEANS
• Run your unit tests first locally (because they’re fast).
• Checking in your changes triggers the continuous
integration server running your Selenium tests (slow
because they are in the browser).
• Cruise Control gives you a web-based heads up when you
fail or pass tests.
• Joy.

THANKS!
:)
Chris Blow
http://unthinkingly.com
User Experience @ Meedan.net