How are 'unit tests' typically structured?

Unit tests are typically structured as small, individual test functions designed to verify the functionality of a specific section of code, usually a single function or method. This approach allows developers to isolate each part of the codebase, making it easier to identify and fix bugs, ensure that each unit performs as expected, and all edge cases are tested comprehensively.

By having unit tests broken down into small, manageable pieces, developers can run tests frequently without needing to execute a large block of code, facilitating a quick feedback loop during the development process. This structure also promotes better organization of test cases and increases readability, making it easier for others (or the original developer at a later time) to understand what is being tested and why.

In contrast, other structures, such as large blocks of code or classes that inherit from others, would not provide the same level of granularity or focus necessary for effective unit testing. Integration tests, which assess how multiple components work together, serve a different purpose and generally operate on a broader scope, making them unsuitable for the definition of unit tests.