linting

Linting is the automated analysis of source code to flag potential errors, stylistic issues, and suspicious constructs. The term originated with the Unix program lint, which examined C code for problematic patterns. Modern linting covers many languages and domains, and is a form of static analysis that does not require executing the program.

Lint tools apply a set of rules to identify problems such as undefined variables, unreachable code, type inconsistencies, or deviations from a project’s style guide. Language-specific linters include ESLint for JavaScript, PyLint for Python, RuboCop for Ruby, and golint for Go, while general-purpose linters can analyze configuration files, templates, or scripts. They report issues with severity levels and may offer automated fixes when possible.

Use of linting typically involves integration into development workflows and tooling. Linters can run in editors, from the command line, in continuous integration pipelines, or as pre-commit checks. Projects customize rules and suppressions to fit their standards, and developers may configure ignore lists or per-file exceptions.

Benefits of linting include early detection of defects, improved code readability, and consistency across a codebase. Limitations include the potential for false positives, the need for upfront configuration, possible performance impacts, and the fact that linting does not replace testing or debugging. Modern tooling often expands linting beyond style to include more advanced static analysis, security checks, and quality metrics.