A VS Code extension that shows interface implementations in Go code using gutter icons (similar to GoLand/IntelliJ), addressing the issue described in golang/go#56695. Features intelligent caching for optimal performance.
Features
CodeLens for Interfaces: Shows "N implementations" above interface definitions with clickable navigation
CodeLens for Types: Shows "Implements: Interface1, Interface2..." above struct definitions
Gutter Icons: Visual indicators in the editor gutter for interfaces and implementations
Smart Navigation:
Single implementation: Navigate directly
Multiple implementations: Show quick-pick menu with file locations
Bidirectional Discovery: Find implementations from interfaces AND find interfaces from implementations
Intelligent Caching: Document-level caching with automatic invalidation for optimal performance
Real-time Updates: CodeLens and gutter icons update automatically as you modify code
Configurable Display: Toggle CodeLens and gutter icons independently
How it Works
The extension uses VS Code's built-in executeImplementationProvider command which leverages gopls (Go language server) to find interface implementations. This provides accurate, bidirectional navigation without custom parsing.