\
**Category:** Ruby\
**Created:** [March 12, 2009, 6:00am UTC](https://www.ruby-forum.com/t/assert-xhtml-test-your-html-by-example/162627 "2009-03-12T06:00:40Z")\
**Posts on this page:** 4\
**Page:** 1
**Author:**  [@Phlip](https://www.ruby-forum.com/u/Phlip)\
**Post date:** [March 12, 2009, 6:00am UTC](https://www.ruby-forum.com/t/assert-xhtml-test-your-html-by-example/162627/1 "2009-03-12T06:00:40Z")
Rubies:
My quest to get the maximum coverage & diagnostics from the leanest
possible
tests has reached a new level.
This is a Rails functional test on an HTML form:
```
user = users(:Moses)
get :edit_user, :id => user.id
assert_xhtml do
form :action => '/users' do
fieldset do
legend 'Personal Information'
label 'First name'
input :type => 'text',
:name => 'user[first_name]'
:value => user.first_name
end
end
end
```
That’s all. The assertion expects a form with a given action, containing
a
fieldset, a legend, a label, and a populated text input field. The
assertion
forgives any other details, such as intervening structural tags, and
complains
if any required detail is missing, out of order, or ill-formed.
You test HTML by writing an example of what you expect, excluding
details you
don’t care about.
When it fails, the assertion will print out your reference HTML, and
your sample
HTML from your web page.
The assertion faults if…
- any attribute does not match exactly
- any text content does not match, stripped
- any node is not found at all
- any node is found out of order
The assertion does not fail if
- nodes contain un-specified attributes
- the DOM contains any un-specified tags (,
, etc.)
Here’s the assertion checking that a list appears in collating order:
```
assert_xhtml SAMPLE_LIST do
ul :style => 'font-size: 18' do
li 'model' do
li 'Billings criteria'
li 'Billings report'
li 'Sales report'
end
end
end
```
The assertion takes a block that renders into a Nokogiri::HTML::Builder.
Any
HTML it can build, you can specify by example.
That freedom causes two issues: The ‘self’ context is different inside
this
block, so you must pass variables in as closures. And an element with
the same
name as a Builder method, such as .select, need a bang: .select!
Get the assertion, from assert2-0.3.8.gem, with these incantations:
gem install assert2 nokogiri
require ‘assert2/xhtml’ # for Test::Unit::TestCase and derivatives
Those of you using RSpec will know how to apply this Gist:
[An RSpec HTML matcher that nests contexts · GitHub](http://gist.github.com/76136)
Good hunting!
---
**Author:**  [@Phlip](https://www.ruby-forum.com/u/Phlip)\
**Post date:** [March 12, 2009, 9:38pm UTC](https://www.ruby-forum.com/t/assert-xhtml-test-your-html-by-example/162627/2 "2009-03-12T21:38:30Z")
On Wed, Mar 11, 2009 at 11:58 PM, Phlip [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:
> assert\_xhtml do
>
> When it fails, the assertion will print out your reference HTML, and your
>
> ```
> li 'Billings report'
>
> ```
>
> block, so you must pass variables in as closures. And an element with the
> [An RSpec HTML matcher that nests contexts · GitHub](http://gist.github.com/76136)
> Any interest in just incorporating this into the lib? So an RSpec user
> could say “require ‘assert2/rspec’” or something?
---
**Author:**  [@Phlip](https://www.ruby-forum.com/u/Phlip)\
**Post date:** [March 12, 2009, 11:30pm UTC](https://www.ruby-forum.com/t/assert-xhtml-test-your-html-by-example/162627/3 "2009-03-12T23:30:38Z")
> > Those of you using RSpec will know how to apply this Gist:
> >
> > [An RSpec HTML matcher that nests contexts · GitHub](http://gist.github.com/76136)
>
> Any interest in just incorporating this into the lib? So an RSpec user
> could say “require ‘assert2/rspec’” or something?
Yabsolutely!
And my boss just hit the “crunch mode” button today, after 2 years of
pure
sustainable pace. Guess it’s time to pay out the energy we have stored
up, huh?
(No RSpec onsite. Sorry!)
---
**Author:**  [@Phlip](https://www.ruby-forum.com/u/Phlip)\
**Post date:** [March 13, 2009, 10:11pm UTC](https://www.ruby-forum.com/t/assert-xhtml-test-your-html-by-example/162627/4 "2009-03-13T22:11:59Z")
Amazing stuff 😃
Can’t wait to test it out