The testing pyramide

Source

The testing pyramide is a conceptual model that shows how to correctly distribute unit, integration and end-to-end tests.

1. The more high-level you get, less tests you should have.
2. Write tests with different granularity.

1. Following the model helps finding mistakes on low levels.
2. Saves money.
3. Ensures a balance between speed of feedback and complete verification.

• ice cream cone (reversed pyramid)
• high-level tests repeat low-level ones.
• isolation break: unit tests access the database or network and become integration testing.