Test double ‐ Mock

Observations

• Mocks are used to replace the interface

What mocks are used for

• It is used to check if the function is called or not.
• It is used to check if the right parameters are passed or not.
• It is also used to check how many times the function is called.

What it is not used for

• To check the return type of the function it is calling.

Example Scenario of usage

• We call a server using retrofit
• We actually call an abstract function of an interface and the abstract function communicates to a real server and returns data.
• Using mocks we can make the abstract function communicate to the mock server and return data.