Software testing: Lecture 12

Question 1

Reasons for testing

Answer 1

1. Detection of defects
2. Support the design and implementation of a module
3. Prevent the introduction of defects
4. Document the behaviour of a system
5. Demonstrate that a system meets it specification

Question 2

Testing concepts

Answer 2

1. Interfaces describes the expected service of a system: (e.g. inputs, outputs, non-functional characteristics)
2. Failures are observations of a system implementation’s deviation from expected behaviour
3. Defects (or bugs, faults) are the deduced causes of failure in a system, an incorrect variable assignment, or an invalid pointer reference, for example
4. Slips (or errors) are the actions by programmers that introduce defects into a software system.

Question 3

Scales of testing

Answer 3

1. Unit tests
2. Integration tests
3. Acceptance (or system) tests

Question 4

Behaviour Driven Development (BDD) User Stories

Answer 4

Narrative: [description]
As an [actor]
I want to [action]
So that [rationale]

Narrative: manage account balance
As a bank account holder
I want to make transactions on my bank account
So that I can manage my cashflow

Scenario: [description]
Given [how things begin]
When [action taken]
Then [outcome]
And [more outcomes...]

Scenario: transfer an amount to another account
Given a bank account for “Tony”
When I transfer $100 to the bank account for “Tony”
Then the balance for “Tony” should be $100
And my balance should be $0