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

Object-Oriented Programming (OOP)

A programming paradigm that organizes software design around objects containing data and behavior.

A surface indication in code that usually corresponds to a deeper problem in the system, suggesting the need for refactoring.

Immutable Object

An object whose state cannot be modified after creation, providing thread safety and predictable behavior in concurrent systems.

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

Restructuring existing code without changing its external behavior to improve readability, maintainability, and performance.

A step-by-step procedure for solving a problem or performing a computation, defined as a finite sequence of instructions.

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