Programming Concepts Beginner

What is Unit Testing?

Testing individual components or functions of a program in isolation to verify they work correctly.

Unit tests verify that individual functions, methods, or classes produce correct output for given inputs. They run fast, test in isolation (using mocks/stubs for dependencies), and provide immediate feedback when code breaks.

Popular frameworks include pytest (Python), JUnit (Java), Jest (JavaScript), and PHPUnit (PHP). Test-Driven Development (TDD) writes tests before implementation. Good tests are independent, repeatable, and cover edge cases.

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Related Terms

SOLID Principles

Five design principles for writing maintainable, flexible object-oriented code: Single Responsibility, Open-Closed, Liskov Substitution, Interface Segregation, and Dependency Inversion.

A linear data structure where elements are stored in nodes, each containing data and a pointer to the next node in the sequence.

Two memory regions: the stack stores function call data with automatic cleanup, while the heap stores dynamically allocated objects.

The practice of designing application programming interfaces that are consistent, intuitive, and maintainable for developers to consume.

A software development methodology that emphasizes iterative development, collaboration, and rapid response to change.

The smallest unit of execution within a process, allowing concurrent operations to run within a single program.

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