peripheryapp/periphery
Periphery
Periphery ist ein statisches Analysetool und ein Detektor für toten Code in Swift-Projekten. Es identifiziert nicht referenzierte Klassen, Structs, Funktionen und Eigenschaften und dient als API-Oberflächen-Optimierer, um öffentliche Deklarationen zu finden, die auf internen Zugriff beschränkt werden können.
Das Tool umfasst spezialisierte Scans für Interface-Builder-Dateien wie Storyboards und XIBs, um sicherzustellen, dass UI-verknüpfte Elemente nicht fälschlicherweise als ungenutzt markiert werden. Es bietet zudem eine automatisierte Code-Bereinigung, um identifizierten toten Code und ungenutzte Parameter direkt aus den Quelldateien zu entfernen.
Die Analysefunktionen decken die Erkennung redundanter Protokolle, ungenutzter Enum-Cases, unnötiger Imports und Eigenschaften, die nur zugewiesen, aber nie gelesen werden, ab. Das System verwaltet technische Schulden durch Baseline-Vergleichsfilter und unterstützt Projekte mit gemischten Sprachen, indem es Symbole bewahrt, die für die Objective-C-Runtime exponiert sind.
Periphery lässt sich über YAML-basierte Konfigurationen in Build-Systeme und CI-Pipelines integrieren und kann Analyseergebnisse in mehreren Industriestandard-Formaten exportieren.
Features
- Dead Code Cleanup - Statically analyzes Swift projects to identify unreferenced classes, structs, functions, and properties.
- Call Graph Traversals - Identifies unreferenced symbols by building and traversing a dependency graph of declarations and their call sites.
- Unused Code Identification - Uses binary index store data to identify unused code without requiring a full project rebuild.
- Swift Linters - Provides static analysis of Swift project graphs to find redundant declarations and unused imports.
- Compiler Index Store Integration - Processes binary index stores from the Swift compiler to efficiently determine symbol usage.
- Interface Builder Parsing - Scans Storyboard and XIB files to ensure UI-connected members are not incorrectly flagged as unused.
- Redundant Accessibility Detection - Identifies declarations marked public that are never referenced from outside their home module.
- Accessibility Level Analysis - Swift Unused Code Detector identifies public declarations that can be made private because they are only used internally.
- API Surface Reduction - Identifies public declarations that can be restricted to internal access to optimize the module's API surface.
- Dead Code Removal - Automatically removes identified dead code and unused parameters directly from Swift source files.
- Interface Builder Analyzers - Parses XIB and storyboard files to ensure UI-connected members are not incorrectly flagged as unused.
- Mixed-Language Project Support - Retains declarations accessible to the runtime to prevent false positives in multi-language codebases.
- Assign-Only Property Detection - Identifies properties that are assigned values but never read, including those in structs with synthesized initializers.
- Redundant Protocol Detection - Identifies protocols that are conformed to but never used as existential types or for generic specialization.
- Runtime Interop Analysis - Preserves symbols exposed to the Objective-C runtime to prevent false positives in mixed-language projects.
- Synthesized Code Handling - Preserves properties on types with compiler-generated code to avoid marking synthesized members as unused.
- Unused Enum Case Detection - Identifies individual cases within non-raw-representable enumerations that are never referenced.
- Unused Import Detection - Identifies import statements that are not required by any declaration in the source file.
- Unused Parameter Detection - Identifies parameters in functions, protocols, and overridden methods that are never accessed.
- Baseline-Based Debt Management - Provides a mechanism to track known unused code in a baseline file to isolate new regressions from legacy debt.
- General Utilities - Identifies unused code in Swift projects.
