Behaviour Driven Development is a powerful collaboration technique that can empower teams to deliver higher value features to the business faster and more effectively. But although Behaviour Driven Development is based on a number of simple principles, it can go dramatically wrong in a myriad of different ways. In this talk we discuss twelve BDD anti-patterns we frequently encounter in real-world BDD projects, anti-patterns that can dramatically reduce the effectiveness of BDD as a practice, and that can even cause BDD adoption to fail entirely. Looking at everything from insufficient collaboration practices to poor use of test automation tooling, from teams that test too much to teams that forget the most important scenarios, we will look at the many different ways that BDD can go wrong, and how it should be done. We will use real-world examples to illustrate each of these anti-patterns. You will learn how to spot these issues in your own projects, and more importantly how to avoid them in the first place.

1. Stories from the trenches about how not to do BDD
Twelve BDD Antipatterns

2. John
Ferguson
Smart
Introductions
“I help teams of smart people
learn to work together more efficiently,
to deliver better software faster”

3. To deliver
software that
matters
And a common
language to build
a shared
understanding
Using examples at
multiple levels
Collaborate to
discover
requirements and
identify uncertainty
The essence of BDD

4. To deliver
software that
matters
And a common
language to build
a shared
understanding
Using examples at
multiple levels
Collaborate to
discover
requirements and
identify uncertainty
The essence of BDD

5. To deliver
software that
matters
And a common
language to build
a shared
understanding
Using examples at
multiple levels
Collaborate to
discover
requirements and
identify uncertainty
The essence of BDD

6. To deliver
software that
matters
And a common
language to build
a shared
understanding
Using examples at
multiple levels
Collaborate to
discover
requirements and
identify uncertainty
The essence of BDD

7. To deliver
software that
matters
And a common
language to build
a shared
understanding
Using examples at
multiple levels
Collaborate to
discover
requirements and
identify uncertainty
The essence of BDD

8. The business owner
tells the business
analyst what he wants
1
2
The business
analyst writes a
requirements
document
3
The developer
translates the
requirements
into software
4 The tester
translates the
requirements
into test cases 5 The technical
writer translates
the software
into functional
and technical
documentation
A traditional development process
How does it work?

9. The business owner
tells the business
analyst what he wants
1
2
The business
analyst writes a
requirements
document
3
The developer
translates the
requirements
into software
4 The tester
translates the
requirements
into test cases 5 The technical
writer translates
the software
into functional
and technical
documentation
A traditional development process
How does it work?

10. The business owner
tells the business
analyst what he wants
1
2
The business
analyst writes a
requirements
document
3
The developer
translates the
requirements
into software
4 The tester
translates the
requirements
into test cases 5 The technical
writer translates
the software
into functional
and technical
documentation
A traditional development process
How does it work?

11. The business owner
tells the business
analyst what he wants
1
2
The business
analyst writes a
requirements
document
3
The developer
translates the
requirements
into software
4 The tester
translates the
requirements
into test cases 5 The technical
writer translates
the software
into functional
and technical
documentation
A traditional development process
How does it work?

12. The business owner
tells the business
analyst what he wants
1
2
The business
analyst writes a
requirements
document
3
The developer
translates the
requirements
into software
4 The tester
translates the
requirements
into test cases 5 The technical
writer translates
the software
into functional
and technical
documentation
A traditional development process
How does it work?

13. The business owner
tells the business
analyst what he wants
1
2
The business
analyst writes a
requirements
document
3
The developer
translates the
requirements
into software
4 The tester
translates the
requirements
into test cases 5 The technical
writer translates
the software
into functional
and technical
documentation
A traditional development process
How does it work?

14. The business owner
tells the business
analyst what he wants
1
2
The business
analyst writes a
requirements
document
3
The developer
translates the
requirements
into software
4 The tester
translates the
requirements
into test cases 5 The technical
writer translates
the software
into functional
and technical
documentation
A traditional development process
How does it work?

15. The business owner
tells the business
analyst what he wants
1
2
The business
analyst writes a
requirements
document
3
The developer
translates the
requirements
into software
4 The tester
translates the
requirements
into test cases 5 The technical
writer translates
the software
into functional
and technical
documentation
A traditional development process
How does it work?

16. The business owner
tells the business
analyst what he wants
1
2
The business
analyst writes a
requirements
document
3
The developer
translates the
requirements
into software
4 The tester
translates the
requirements
into test cases 5 The technical
writer translates
the software
into functional
and technical
documentation
A traditional development process
How does it work?

17. The business owner
tells the business
analyst what he wants
1
2
The business
analyst writes a
requirements
document
3
The developer
translates the
requirements
into software
4 The tester
translates the
requirements
into test cases 5 The technical
writer translates
the software
into functional
and technical
documentation
A traditional development process
How does it work?

18. The business owner
tells the business
analyst what he wants
1
2
The business
analyst writes a
requirements
document
3
The developer
translates the
requirements
into software
4 The tester
translates the
requirements
into test cases 5 The technical
writer translates
the software
into functional
and technical
documentation
A traditional development process
How does it work?

19. How does it work?
The business owner
and the business
analyst have a
conversation about
what he needs.
1
2
3
4 The tester uses
these scenarios
as the basis for
her tests
5
The automated tests provide
feedback on progress and help
document the application
The business analyst,
the developer and the
tester elaborate the
requirements together.
The scenarios guide the
developer and act as
automated tests
They define
requirements as
structured, English-
language format
"scenarios"
A BDD development process

20. How does it work?
The business owner
and the business
analyst have a
conversation about
what he needs.
1
2
3
4 The tester uses
these scenarios
as the basis for
her tests
5
The automated tests provide
feedback on progress and help
document the application
The business analyst,
the developer and the
tester elaborate the
requirements together.
The scenarios guide the
developer and act as
automated tests
They define
requirements as
structured, English-
language format
"scenarios"
A BDD development process

21. How does it work?
The business owner
and the business
analyst have a
conversation about
what he needs.
1
2
3
4 The tester uses
these scenarios
as the basis for
her tests
5
The automated tests provide
feedback on progress and help
document the application
The business analyst,
the developer and the
tester elaborate the
requirements together.
The scenarios guide the
developer and act as
automated tests
They define
requirements as
structured, English-
language format
"scenarios"
A BDD development process

22. How does it work?
The business owner
and the business
analyst have a
conversation about
what he needs.
1
2
3
4 The tester uses
these scenarios
as the basis for
her tests
5
The automated tests provide
feedback on progress and help
document the application
The business analyst,
the developer and the
tester elaborate the
requirements together.
The scenarios guide the
developer and act as
automated tests
They define
requirements as
structured, English-
language format
"scenarios"
A BDD development process

23. How does it work?
The business owner
and the business
analyst have a
conversation about
what he needs.
1
2
3
4 The tester uses
these scenarios
as the basis for
her tests
5
The automated tests provide
feedback on progress and help
document the application
The business analyst,
the developer and the
tester elaborate the
requirements together.
The scenarios guide the
developer and act as
automated tests
They define
requirements as
structured, English-
language format
"scenarios"
A BDD development process

24. How does it work?
The business owner
and the business
analyst have a
conversation about
what he needs.
1
2
3
4 The tester uses
these scenarios
as the basis for
her tests
5
The automated tests provide
feedback on progress and help
document the application
The business analyst,
the developer and the
tester elaborate the
requirements together.
The scenarios guide the
developer and act as
automated tests
They define
requirements as
structured, English-
language format
"scenarios"
A BDD development process

25. FeedbackPitch
The three forms of balance
Timing

26. FeedbackPitch
The three forms of balance
Timing

27. FeedbackPitch
The three forms of balance
Timing

28. FeedbackPitch
The three forms of balance
Timing

29. FeedbackPitch
The three forms of balance
Timing

30. Timing

31. “Out to lunch”
Antipattern #1

32. “The Cucumber Salad”
Antipattern #2

33. “The Cucumber Salad”
Feature: Display customer details
As an user
I want to view the customer's personal profile
In order to access the personal information on the customer
Scenario: Customer Profile field 'Gender'
Given I am logged into the application
And I have displayed the customer
When I view the customer profile on the summary screen
Then I should see the Gender field (field type: Dropdown - read only information)
Scenario: Customer Profile ‘DOB/Age' field
Given I am logged into the application
And I have displayed the customer
When I view the Personal Profile on the Summary screen
Then I should see the DOB/Age field (DOB field type: Date, format: dd mmm yyyy -
read only) (Age field type:read only - numeric) under Personal Profile
And it should be blank if no value returned
Scenario: Customer Profile 'Marital Status' field
Scenario: Customer Profile 'Dependents' field

34. “Cucumber as a Test Tool”
Antipattern #3

35. Pitch

36. “Aimless requirements”
Antipattern #4

37. “Aimless requirements”
Feature: Display customer details
As a user
I want to view the customer's profile details
So that I can see the personal information on the customer

38. “Aimless requirements”
Feature: Display customer details
As a user
I want to view the customer's profile details
So that I can see the personal information on the customer

39. “Aimless requirements”
Feature: Display customer details
As a user
I want to view the customer's profile details
So that I can see the personal information on the customer
Feature: Locate a customer
In order to propose more relevant services to my customers
As a financial adviser
I want to view a customer's profile details

40. “Aimless requirements”
Feature: Display customer details
As a user
I want to view the customer's profile details
So that I can see the personal information on the customer
Feature: Locate a customer
In order to propose more relevant services to my customers
As a financial adviser
I want to view a customer's profile details
In order to propose more relevant services to my customers
What is the real
business goal?

41. “Aimless requirements”
Feature: Display customer details
As a user
I want to view the customer's profile details
So that I can see the personal information on the customer
Feature: Locate a customer
In order to propose more relevant services to my customers
As a financial adviser
I want to view a customer's profile details
As a financial adviser
What is the real
business goal?
What is the context of the
user who needs this feature?

42. “Aimless requirements”
Feature: Display customer details
As a user
I want to view the customer's profile details
So that I can see the personal information on the customer
Feature: Locate a customer
In order to propose more relevant services to my customers
As a financial adviser
I want to view a customer's profile details
What is the real
business goal?
What is the context of the
user who needs this feature?

43. “Aimless requirements”
Feature: Authenticate using social media
In order to access the application more easily
As a new user
I want to authenticate using social media instead of having to provide
a username and password

44. “Aimless requirements”
Feature: Authenticate using social media
In order to access the application more easily
As a new user
I want to authenticate using social media instead of having to provide
a username and password
Feature: Authenticate using social media
In order to access the application more easily
As a new user
I want to authenticate using social media instead of having to provide
a username and password
Scenario: Login via LinkedIn
Scenario: Login via Twitter

45. “Aimless requirements”
Feature: Authenticate using social media
In order to access the application more easily
As a new user
I want to authenticate using social media instead of having to provide
a username and password
Feature: Authenticate using social media
In order to access the application more easily
As a new user
I want to authenticate using social media instead of having to provide
a username and password
Scenario: Login via LinkedIn
Scenario: Login via Twitter

46. “Aimless requirements”
Feature: Authenticate using social media
In order to access the application more easily
As a new user
I want to authenticate using social media instead of having to provide
a username and password
Feature: Authenticate using social media
In order to access the application more easily
As a new user
I want to authenticate using social media instead of having to provide
a username and password
Scenario: Login via LinkedIn
Scenario: Login via Twitter

47. “Aimless requirements”
Feature: Authenticate using social media
In order to access the application more easily
As a new user
I want to authenticate using social media instead of having to provide
a username and password
Feature: Authenticate using social media
In order to access the application more easily
As a new user
I want to authenticate using social media instead of having to provide
a username and password
Scenario: Login via LinkedIn
Scenario: Login via Twitter
Scenario: Login via Facebook

48. “Aimless requirements”
Feature: Authenticate using social media
In order to access the application more easily
As a new user
I want to authenticate using social media instead of having to provide
a username and password
Feature: Authenticate using social media
In order to access the application more easily
As a new user
I want to authenticate using social media instead of having to provide
a username and password
Scenario: Login via LinkedIn
Scenario: Login via Twitter
Scenario: Login via Facebook

49. “Boring requirements”
Antipattern #5

50. “Boring scenarios”
Scenario Outline: User tries to log on to application with invalid credentials
Given I am a registered user
When I login as <username> with password <password>
Then I should not be allowed to logon
And I should see the error message <error-message>
Examples:
| username | password | message |
| scott | | Please enter a password |
| | tiger | Please enter a username |
| scott | wrong | Invalid username or password |

51. “Boring scenarios”
Scenario Outline: User tries to log on to application with invalid credentials
Given I am a registered user
When I login as <username> with password <password>
Then I should not be allowed to logon
And I should see the error message <error-message>
Examples:
| username | password | message |
| scott | | Please enter a password |
| | tiger | Please enter a username |
| scott | wrong | Invalid username or password |
UX concerns

52. “Boring scenarios”
Scenario Outline: User tries to log on to application with invalid credentials
Given I am a registered user
When I login as <username> with password <password>
Then I should not be allowed to logon
And I should see the error message <error-message>
Examples:
| username | password | message |
| scott | | Please enter a password |
| | tiger | Please enter a username |
| scott | wrong | Invalid username or password |
UX concerns
OK, but what else?

53. “Eyes on the screen”
Antipattern #6

54. “Eyes on the screen”
19
Scenario: User logs on to application
Given I am an authorised user
When I enter ‘scott’ into the username field
And I enter ‘tiger’ into the password field
And I click on ‘login’
Then the application home page should open

55. “Eyes on the screen”
19
Scenario: User logs on to application
Given I am an authorised user
When I enter ‘scott’ into the username field
And I enter ‘tiger’ into the password field
And I click on ‘login’
Then the application home page should open
Scenario: User logs on to application
Given I am an authorised user
When I login with a valid username and password
Then I should be provided access to my accounts

56. “Eyes on the screen”
19
Scenario: User logs on to application
Given I am an authorised user
When I enter ‘scott’ into the username field
And I enter ‘tiger’ into the password field
And I click on ‘login’
Then the application home page should open
Scenario: User logs on to application
Given I am an authorised user
When I login with a valid username and password
Then I should be provided access to my accounts
When I login with a valid username and password

57. “Eyes on the screen”
19
Scenario: User logs on to application
Given I am an authorised user
When I enter ‘scott’ into the username field
And I enter ‘tiger’ into the password field
And I click on ‘login’
Then the application home page should open
Scenario: User logs on to application
Given I am an authorised user
When I login with a valid username and password
Then I should be provided access to my accountsThen I should be provided access to my accounts

58. “Eyes on the screen”
19
Scenario: User logs on to application
Given I am an authorised user
When I enter ‘scott’ into the username field
And I enter ‘tiger’ into the password field
And I click on ‘login’
Then the application home page should open
Scenario: User logs on to application
Given I am an authorised user
When I login with a valid username and password
Then I should be provided access to my accounts

59. “Top-heavy scenarios”
Antipattern #7

60. “Not having all the cards”
Antipattern #8

61. “Not having all the cards”
22
Scenario: Find a customer by various criteria
Given I am logged into the application
When I click Search
Then I will see search criteria options to search for the customer
by customer name, date of birth, and account number

62. “Not having all the cards”
22
Scenario: Find a customer by various criteria
Given I am logged into the application
When I click Search
Then I will see search criteria options to search for the customer
by customer name, date of birth, and account number

63. “Not having all the cards”
22
Scenario: Find a customer by various criteria
Given I am logged into the application
When I click Search
Then I will see search criteria options to search for the customer
by customer name, date of birth, and account number
Scenario: Find a customer by name
Given the following customers exist:
| id | first name | last name |
| 100 | Sarah-Jane | Smith |
| 101 | Sarah | Smith |
When I search for a customer using the following search criteria:
| name | Sarah-Jane Smith |
Then I should display the following customer:
| id | first name | last name |
| 100 | Sarah-Jane | Smith |

64. “Not having all the cards”
22
Scenario: Find a customer by various criteria
Given I am logged into the application
When I click Search
Then I will see search criteria options to search for the customer
by customer name, date of birth, and account number
Scenario: Find a customer by name
Given the following customers exist:
| id | first name | last name |
| 100 | Sarah-Jane | Smith |
| 101 | Sarah | Smith |
When I search for a customer using the following search criteria:
| name | Sarah-Jane Smith |
Then I should display the following customer:
| id | first name | last name |
| 100 | Sarah-Jane | Smith |
Well-defined inputs

65. “Not having all the cards”
22
Scenario: Find a customer by various criteria
Given I am logged into the application
When I click Search
Then I will see search criteria options to search for the customer
by customer name, date of birth, and account number
Scenario: Find a customer by name
Given the following customers exist:
| id | first name | last name |
| 100 | Sarah-Jane | Smith |
| 101 | Sarah | Smith |
When I search for a customer using the following search criteria:
| name | Sarah-Jane Smith |
Then I should display the following customer:
| id | first name | last name |
| 100 | Sarah-Jane | Smith |
Well-defined inputs
Well-defined outcomes

66. “Scenario overload”
Antipattern #9

67. “Scenario overload”
24
Scenario: The account earns 4% interest when the balance is over $10000
Given a bonus saver account with a end-of-month balance of 12000
When interest is calculated
Then the monthly interest earned should be 40
Scenario: The account earns 2% interest when the balance is less than $10000
Given a bonus saver account with a end-of-month balance of 9000
When interest is calculated
Then the monthly interest earned should be 15
Scenario: The account earns 4% interest when the balance is over $10000 and no more than
$300 has been withdrawn
Given a bonus saver account with a end-of-month balance of 12000
And a previous end-of-month balance of $12300
When interest is calculated
Then the monthly interest earned should be 40
Scenario: The account earns 2% interest when the balance is over $10000 and more than
$300 has been withdrawn
Given a bonus saver account with a end-of-month balance of 12000
And a previous end-of-month balance of $12400
When interest is calculated
Then the monthly interest earned should be 15

68. “Scenario overload”
25

69. “Scenario overload”
25
Scenario Outline: Bonus saver account
Given a bonus saver account with an end-of-month balance of <balance>
And a previous end-of-month balance of <previous>
When the interest is calculated
Then the applicable interest rate should be <rate>
And <interest-earned> should be deposited into the account
Examples:
balance | previous | rate| earned| rule
10000 | 10000 | 4 | 33.33 |
9000 | 9000 | 2 | 15.00 | Under 10000 earns 2%
10000 | 10300 | 4 | 33.33 | Over 10000 earns 4%
9000 | 9301 | 1 | 7.5 | Under $10000 with over 300 withdrawn earns 1%
10000 | 10301 | 2 | 16.67 | Over $10000 with over $300 withdraw earns 2%

70. “Scenario overload”
26

71. “Scenario overload”
26
Scenario Outline: Bonus saver account
Given a bonus saver account with an end-of-month balance of <balance>
And a previous end-of-month balance of <previous-balance>
When the interest is calculated
Then the applicable interest rate should be <percentage-interest>
And <interest-earned> should be deposited into the account
Examples:
balance | previous-balance | percentage | earned |
10000 | 10000 | 4 | 33.33 |
10001 | 10000 | 4 | 33.34 |
1000 | 1000 | 2 | 1.67 |
9000 | 9000 | 2 | 15.00 |
10000 | 10300 | 4 | 33.33 |
20000 | 20000 | 4 | 100 |
10000 | 10301 | 2 | 16.67 |
9000 | 9301 | 1 | 7.5 |
20000 | 20301 | 1 | 50 |
100000 | 100301 | 1 | 250 |

72. “Cucumber test scripts”
Antipattern #10

73. “Cucumber test scripts”
28

74. “Cucumber test scripts”
29

75. “Tech-speak Scenarios”
Antipattern #11

76. “Techie Scenarios”
31
Scenario: Propose user branch when user logs in
Given I am an authorized staff member
When I log on using my valid credentials
Then the following branches should be available in the branch drop-down
| Branch name |
| George Street |
| Market Street |
| Liverpool Street |

77. Feedback

78. “Incommunicado scenarios”
Antipattern #12

79. “Incommunicado scenarios”
34

80. “Incommunicado scenarios”
35

81. “Incommunicado scenarios”
36

82. FeedbackPitch
So keep your balance!
Timing

83. Questions?
John Ferguson Smart
john.smart@wakaleo.com
wakaleo
http://www.wakaleo.com