go-file-splitter

A CLI tool that splits Go source files into individual files by function. It can separate public functions, methods, and test functions into individual files.

Features

• Public Function Splitting: Splits public functions (starting with uppercase) into individual files
• Public Method Splitting: Splits struct public methods (with two strategies to choose from)
• Test Function Splitting: Splits test functions starting with Test into individual files
• Constants, Variables, and Type Definitions: Groups public definitions into common.go
• Comment Preservation: Properly handles doc comments, inline comments, and standalone comments
• Import Optimization: Only imports packages that are actually used

Installation

go install github.com/sters/go-file-splitter@latest

Usage

go-file-splitter [options] <directory>

Options

• -public-func (default: true): Split public functions into individual files
• -test-only: Split only test functions (overrides -public-func)
• -method-strategy <strategy>: Specify method splitting strategy
  • separate (default): Split each method into individual files
  • with-struct: Group struct and its methods in the same file
• -version: Show version information

Examples

# Split public functions in current directory (default behavior)
go-file-splitter .

# Split public functions in specific directory
go-file-splitter ./pkg/mypackage

# Split only test functions
go-file-splitter -test-only ./test

# Explicitly split public functions
go-file-splitter -public-func ./src

# Split with methods grouped with their structs
go-file-splitter -method-strategy with-struct ./pkg

# Split methods into individual files (default behavior)
go-file-splitter -method-strategy separate ./pkg

Output Structure

Default Strategy (separate)

Each public function and method is split into individual files:

output/
├── common.go              # Constants, variables, type definitions
├── function_name.go       # Public functions
├── type_name_method.go    # Methods (individual files)
└── test_function.go       # Test functions

with-struct Strategy

Structs and their methods are grouped in the same file:

output/
├── common.go              # Constants, variables, other type definitions
├── function_name.go       # Public functions
├── type_name.go           # Struct with all its methods
└── test_function.go       # Test functions

Recent Improvements

Recent updates to this tool include:

• Improved Test Coverage: Achieved 74.8% coverage
• Code Quality Improvements: Resolved all golangci-lint errors
• Refactoring: Split complex functions to improve maintainability
• Import Optimization: Only imports packages that are actually used
• Enhanced Comment Handling: Properly handles standalone and inline comments