5 minute rule for arguments, longer argument than that then let go à doesn’t matter!
Även denna dag började varje pass med teorier som
- Maxwells theory – all is waves
- Galileo - Speed is relavite to any frame of reference
- Equivalence principle
- Einsteins General relativity
Katas
TDD
Unit Tests must comply with FIRST:
FIRST
Fast
Isolated (Independent)
Repeatable
Self verifying
Timely
Fast
Tests need to be fast to be run.
Do not use production data, it contains too much clutter. Construct your data!
Discussion on Golden Copy vs Approval Testing.
Isolated
One fault should make only one test fail
Repeatable
Able to run anywhere repeatably with same result; plain, train, work, home, etc.
Self Verifying
Pass or Fail! Nothing in between or demanding human intervention (like reading logfiles)
Timely
Written first. The test is the specification.
1 code change = 1 test
Given when then
What about METHOD_WHEN_THEN, for a stack the test methods could be:
Push_empty_sizeIsOne
Pop_empty_throwUnderFlow
Push_full_throwOverFlow
Pop_sizeone_empty
Principles
#1 Don’t test private or protected methods.
#2 Testing trumps privacy
· Make private methods package protected
· Or extract into own class
#3 Testing privates implies a design error
Put tests in same package
Preferably in same directory, but deploying without tests is tricky.
Fragile tests
xUnit Patterns à The fragile test “problem”
Interface Sensivity
Do not depend directly on UI-components
Open/Closed Principle (Bertrand Meyer), a class should be open for extension but closed for modification.
The best anticipation of change is change that already happened.
Behaviour Sensitivity
Avoid complex setup and tardown scenarios
Access the tested feature as directly as possibly
Data Sensitivity
Failure because of changed test data. Control your test data!
Context Sensitivity
- Data/time
- Available Memory
- Network Services
- Hardware
Mock out context dependencies. Mock out clock!
Overspecification
Failure because of change in system test should not care about. (The scope of test is too wide).
Sensitive Equality
Failure caused by an over-constrained comparison
- Floating point, whitespace
- Avoid it! J
Preserving tests
FIRST!
Failures are “stop the presses” events. Keep test code clean!
FitNesse
Put fixtures in same project as code under test. Test your fixtures.
Put under source control!
Check in all txt and xml-files under FitNesseRoot.
Same tests, different setup
Use symbolic links
Product
Test One
Test two
Dev
Setup
Symlink à Product
Prod
Setup
Symlink à Product
Special pages
PageHeader Siblings gets page header
Setup
TearDown
Variables
!define NAME {BOB}
The variable NAME is ${NAME}
Can define java definition and environment variables as well.
Old style (ColumnFixture)
- Should be several small tests
- States what to do, not what to test
New style
Misc
- Gesture – tool that changes production code to see if tests fail
- Humble Dialog Box, http://www.objectmentor.com/resources/articles/TheHumbleDialogBox.pdf
- JSP-compiler, creates a servlet basically
- AST – Abstract Syntax Tree
- Velocity – web framework
- jTest – generate unit tests
