Mock Objects, Test Suites, TDD

Question 1

What is a mock object?

Answer 1

Cheap placeholder objects sued to set up certain test conditions.

Question 2

In brief, when do we use a mock object?

Answer 2

When the object being tested has dependencies.

Question 3

In detail, what are the 6 characteristics that prompt the use of Mock Objects?

Answer 3

Object is slow; Non-deterministic; Complex to set up; Doesn’t exist yet; Is a GUI, Has hard to trigger behaviour.

Question 4

From which interface should mock objects be implemented?

Answer 4

The same interface as from which the production code was.

Question 5

What is a test suite?

Answer 5

A construct that allows us to run multiple, independent tests as a single batch of tests.

Question 6

What is the purpose of categories in test suites?

Answer 6

Categories are the concept that enables the grouping of unit tests.

Question 7

From which perspective is TDD implemented?

Answer 7

The users perspective.

Question 8

What are the 2 main benefits of TDD?

Answer 8

Users perspective; Write better code.

Question 9

What do we do is a unit test is overly complex to test?

Answer 9

Re-design the code being tested.

Question 10

Define invariants…

Answer 10

An assertion on an object that doesn’t change. Object state should always be consistent.