Unit Testing 101 presented at ESRI Developer Summit, March 24th, 2009. This talk reviews the key concepts of unit testing, the technologies used by DTSAgile in out development projects.

1. You need
some tests yo!
Dave Bouwman // CTO // DTSAgile

2. the “big” ideas

4. prove
code
works

5. prove
design
works

6. catch
regression

8. unit testing
101

9. Instantiate class under test…
Call Method…
Check Results…
Call Method…
Check Results…

10. good tests are…
independent
repeatable
self-contained*
professional

11. good tests are…
focused

12. tools!

13. “unit testing
on crack”
Scott Hanselman
www.hanselman.com

18. writing
tests

19. simple methods
with simple signatures
mean simple tests

20. complex methods
with complex signatures
mean…
complex tests

21. most
ArcObjects
applications
fall in this
category

22. for testing
design we must

23. separation
of concerns

24. a class has
single
purpose

25. stay
inside
its
box

26. user interface
(events + logic + data access)

27. private void ButtonOn_Click(){
//read values from controls
//apply business logic
//connect to database
//update data
//update interface
}

28. user interface
objects
business
objects
data access
objects

29. Private void ButtonOn_Click(){
//read values from controls
//apply business logic
//send changes to DAL
//connect to database
//update data
//update interface
}

30. n-tier
architecture

31. user interface WPF/Silverlight
objects
business
objects
unit
tests
data access
objects

32. design
patterns yo

33. model
view
controller

34. ASP.NET MVC
released!!
http://asp.net/mvc

35. dependency
management

36. dependencies

37. 1
created
by the
constructor

38. private IAccountRepository _accountRepository;
private IFormsAuthentication _formsAuthentication;
private ILogService _logger;
public AccountController()
{
_accountRepository =
new AccountRepository(_connectionString);
_logger = new Logger();
_formsAuthentication = new FormsAuthentication();
}

39. what about
testing

40. good tests are…
independent
repeatable
self-contained*
professional

41. “tight coupling”
external
dependencies
in the
tests

42. internal
dependencies

43. and
separate
them

44. 2 pass
dependencies
into the
constructor

45. dependency
injection

46. private IAccountRepository _accountRepository;
private IFormsAuthentication _formsAuthentication;
private ILogService _logger;
public AccountController(IAccountRepository accountRepository,
IFormsAuthentication formsAuthentication,
ILogService logger)
{
_accountRepository = accountRepository;
_formsAuthentication = formsAuthentication;
_logger = logger;
}

47. pushed
the
problem
up a
level

48. inversion
of control

49. I need an
AccountController!
configuration
Global.asax.cs

51. Castle Windsor
Spring.NET
mvccontrib IoC
StructureMap
Unity
http://mvccontrib.codeplex.com

52. back to
unit testing…

53. isolated
testing

54. &
mock
fakes
stubs

55. code you
wrote generated
on-the-fly

56. fake
objects

58. stub/mock
objects

60. tools!

61. rhinomocks
http://ayende.com/projects/rhino-mocks.aspx

62. ArcMap
development

63. not
our
box

65. separate
logic
from
wiring

66. emulate
events
fromArcMap

67. my code
sinks…

69. in
ArcMap
Business
IEditEvents Shim
Logic
ArcMap

70. under
test
Business
Test
Logic

71. test
your
code
not
ESRI’s

72. ArcEngine
Applications

73. it’s
our
box

74. design
matters.

76. ArcGIS
Server

77. testing
Web ADF…

78. custom
services

79. COM
Utilities
SOC
COM
Utility
WebService
ArcGIS Server

80. Server
Object
Extensions SOC
SOE
WebService
ArcGIS Server

81. testable
classes
IServerObjectExtension
COM COM
SOE
Utility Utility
(ArcObjects) (ArcObjects)

84. but i’m too
cool for COM…

85. jsunit
D.O.H. Unit Testing
FlexUnit
Silverlight Harness

86. http://mbunit.com
http://testdriven.net
resources http://ASP.NET/mvc
http://mvccontrib.codeplex.com
http://castleproject.org
http://ayende.com/projects/rhino-mocks.aspx

87. i’m in teh codez
writin teztz!

88. and nao u
can too!

89. http://blog.davebouwman.net
dbouwman@dtsagile.com
questions
http://twitter.com/dbouwman
http://slideshare.com/dbouwman