Cucumber & perl

C U C U M B E R A N D P E R LJ O E M C M A H O N < J O E . M C M A H O N @ W H I T E H A T S E C . C O M >

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– T H E D E V E L O P E R

“These programs run my program and verify it operates correctly.”

AAAAAAAAGHH

– N O N - D E V E L O P E R S

“Just tell me what it does!”

Feature: Provider dashboard As a Provider I want to see my account overview on the dashboard So that when I login I can see information that is important to me without digging for it

Scenario: Provider dashboard Given a provider "Hyper Tiny" belonging to "[email protected]" And an RFP called "Help us!" for "Hyper Tiny" And "Hyper Tiny" has a new endorsement from "Tom Rowley" And "Hyper Tiny" has a new endorsement from "Mike Foley" And I am on the homepage When I log in as "[email protected]" with password "testtest" Then I should see "Help us!" And I should see "Tom Rowley" And I should see "Mike Foley"

B E H AV I O R - D R I V E N T E S T S

• Don’t expose the details of how something happens

• Show me what happens

C U C U M B E R T E S T S

• English-like

• Some leading keywords needed

• Specific way to talk about example data in context

• Mostly free-form

F E AT U R E : W H AT Y O U W A N T

• A short description of the thing you expect to see

• Three lines following are not parsed

• Convention is something like

• As X

• In order to Y

• I want to Z



S C E N A R I O : S O M E T H I N G T H AT S H O U L D H A P P E N

• The actual test

• Scenario: describe it

• Given/And: establish conditions

• When: do the thing

• Then/And: what happens



S T E P D E F I N I T I O N S

• Each Given/When/Then is backed by a step definition

• The step definition uses a regex to extract data from the step

• Under the hood we’re still writing tests the old way

Given /^a provider "([^\"]*)" belonging to "([^\"]*)"$/

do |provider, email|

provider = Factory.create(

:provider, :company_name => provider)

user = Factory.create(:user, :email => email)

provider.update_attribute(:user, user)

user.update_attribute(:provider, provider)

end

W E L L , Y E A H , B U T T H AT ’ S R U B Y.

T E S T: : B D D : : C U C U M B E R

• Perl implementation of Cucumber (mostly)

• Lets you write Cucumber tests for your Perl code, with step definitions in Perl

L E T ’ S T E S T S O M E T H I N G !

S T E D M A N W H I T W E L L

•A R C H I T E C T •U T O P I A N •W A C K O

R E F O R M I N G P L A C E N A M E S

• He was “troubled” by the recurrence of place names

• Too many Franklins and Springfields

• He proposed a way to name places based on their geographical coordinates

• Rename every place and it’ll be easy to tell where you are.

• …UTOPIA!

W H I T W E L L’ S S C H E M E

S I L LY, B U T S T R A I G H T F O R W A R D

• We transliterate the numbers according to the table, inserting a sign character if needed after the first vowel

• Very much a behavioral thing: I put in this, I get that

Sydney, Australia (33.55S, 151.17E) Fivul Alabee

Moscow, Russia (55.75N, 37.61E) Uleel Feema

Sunnyvale (37.37N, 122.03W) Inin Beveti

Valparaiso, Chile (33.02S, 71.55W) Isite Navul

B U I L D I N G T H E F E AT U R E T E S T

D E S I G N E D T O H E L P Y O U

• Cucumber tries to tell you the next thing you should do

• You don’t have a feature directory, you need one

• You don’t have a feature, make one

• Your feature steps don’t have step definitions, create them

Feature: Test Acme::Geo::Whitwell conversions

As a developer planning to use Acme::Geo::Whitewell::Name

I want to test the conversion of map coordinates to names and vice versa

In order to get a technically correct good laugh

Background:

Given a usable Acme::Geo::Whitwell::Name class

Scenario: Check names match the Whitwell standard

Given coordinates <latitude> and <longitude> for "<real_name>"

When we convert them

Then we get "<name>"

And the first part contains "s" if the latitude is negative or S

And the second part contains "v" if the longitude is negative or W

Examples:

| latitude | longitude | name | real_name |

| 55.75 | 37.61 | Uleel Feema | Moscow |

| -‐33.02 | -‐71.55 | Isite Navul | Valparaiso |

| -‐33.55 | 151.17 | Isilu Buban | Sydney |

| 37.37 | -‐122.03 | Inin Beveti | Sunnyvale |

| 3.8N | 101.42E | Ipou Boubod | Kuala Lumpur |

| 77.85S | 166.76E | Eeseepu Bymeem | McMurdo Base |

# | 82.50 | -‐62.34 | Bleeg Fnord | Alert |

# | 51.51N | 0.13W | A B | London |

# | 7.933S | 14.37E | X Y | Ascension Island |

# Alert is "Eidut Mevik", London is "Ubub Biv", Ascension is "Eesief Bofee".





Background:








Examples:









# | 51.51N | 0.13W | A B | London |







Background:








Examples:









# | 51.51N | 0.13W | A B | London |



#!perl

use strict;

use warnings;

use Test::More;

use Test::BDD::Cucumber::StepFile;

use Cwd;

Given qr/a usable (\S+) class/, sub { use_ok( $1 ); };





Background:








Examples:









# | 51.51N | 0.13W | A B | London |







Background:








Examples:









# | 51.51N | 0.13W | A B | London |



Given qr/coordinates (\S+) and (\S+)/, sub {

my $c = shift;

$c-‐>stash-‐>{'scenario'}-‐>{'latitude'} = $1;

$c-‐>stash-‐>{'scenario'}-‐>{'longitude'} = $2;

};

When qr/we convert them/, sub {

my $c = shift;

$c-‐>stash-‐>{'scenario'}-‐>{'name'} =

Acme::Geo::Whitwell::Name::to_whitwell(

$c-‐>stash-‐>{'scenario'}-‐>{'latitude'},

$c-‐>stash-‐>{'scenario'}-‐>{'longitude'}

);

};

Then qr/we get "(.*?)"/, sub {

my $c = shift;

my $name = $1;

is($name, $c-‐>stash-‐>{'scenario'}-‐>{'name'},

'name matches');

};





Background:








Examples:









# | 51.51N | 0.13W | A B | London |



Then qr/contains "(\S)" if the (\S+) is negative or (\S)/, sub {

my $c = shift;

my($sign_character, $dimension, $compass_point) = ($1, $2, $3);

my $part = {'latitude' => 0, 'longitude' => 1}-‐>{$dimension};

my $word = (split / /, $c-‐>stash-‐>{'scenario'}-‐>{'name'})[$part];

my $value = $c-‐>stash-‐>{'scenario'}-‐>{$dimension};

my $negative = ($value =~ /^-‐|$compass_point\Z/);

if ($negative) {

ok index($word, $sign_character), 'has negative signifier';

}

else {

is index($word, $sign_character), -‐1, 'no negative signifier';

}

};

D E M O

D E B U G G I N G A S T E P D E F I N I T I O N

• You add the definition, run pherkin, test stays gray

• Either the test didn’t get called (you blew the regex)

• Or the test itself failed to run for some reason

perl -d?

• Way too complex to use directly

• You could eventually find the step definition, but it’s not easy to do by stepping through

• Add $DB::single = 1 to it instead

• Stop is right before the next line to execute

U P S I D E S

• A feature test is way easier to read and understand

• Accessible for non-programmers

• Even writable by non-programmers

• Formalized

• Very free-form

• Easy to work with to get something everyone understands

D O W N S I D E S

• Hidden complexity and “this must be trivial” assumptions

• Still have to write all the test code

• Doesn’t play nice with Test::Unit and the like

• Everybody wants to rule the world

O V E R A L L

• Can help make software make more sense to non-technical folks

• Can help complicated stuff make more sense to technical folks

• More about “what is it supposed to do” than “how does it do this”

T H I S I S A L L V E R Y N I C E …

• …but is anyone using it?

• Yes! WhiteHat uses it for some of our more complex “can X do Y” situations (and we have a lot of X’s)

Feature: Delete a Discussion Response Resource As a Console Operator I want to be able to delete Discussion Responses In order to unclutter the user interface of out of date information

Background: Given a useable NotARealClass::Discussion And a useable NeitherIsThis::Discussion And an Author User And an Operator And a Discussion Resource for a Vuln And a Valid Response

Scenario: Operator tries to delete a discussion response When the Operator calls DELETE on a discussion response Then DELETE response should be successful And the Operator did get one event 'discussion_response_removed' of type 'discussion' Then DELETE response should be forbidden

Scenario: Operator tries to delete a deleted response

Given a Deleted Response

When the Operator calls DELETE on a deleted discussion response

Then DELETE response should be successful

And the Operator did not get one event 'discussion_response_removed' of type 'discussion'

Scenario: Author tries to delete a discussion response

When the Author calls DELETE on a discussion response

Then DELETE response should be forbidden

Scenario: Operator tries delete a non-‐existent response

Given a non-‐existing response_id

When the Operator calls DELETE on a discussion response

Q U E S T I O N S ?

T H A N K S !

Technology

Cucumber & perl