README

A PHP tool to automatically detect API changes between two versions of a PHP project and generate a changelog following SemVer principles.

Features

• ✅ Analysis of public elements only (classes, interfaces, methods, functions, constants)
• ✅ Support for native PHP signatures and PHPDoc
• ✅ Detection of compatible/incompatible changes
• ✅ Automatic SemVer recommendations (major/minor/patch)
• ✅ Markdown changelog generation
• ✅ Support for exclusion patterns
• ✅ Compatible with PHP 7.4+ for analysis, PHP 8.3+ for execution

Installation

composer install

Usage

Basic command

./bin/changelog-generator /path/to/old/version /path/to/new/version

Available options

./bin/changelog-generator old-path new-path [options]

Arguments:
  old-path              Path to the old version of the codebase
  new-path              Path to the new version of the codebase

Options:
  -o, --output=OUTPUT            Output file for the changelog [default: "CHANGELOG.md"]
  -c, --current-version=VERSION  Current version number [default: "1.0.0"]
  -i, --ignore=IGNORE            Patterns to ignore (supports wildcards) [default: ["*/vendor/*", "*/tests/*", "*/test/*"]] (multiple values allowed)
  -f, --format=FORMAT            Output format (markdown, json) [default: "markdown"]
      --dry-run                  Show changes without writing to file
      --strict-semver            Use strict SemVer rules (breaking changes = major even for pre-1.0.0)
  -q, --quiet                    Shows only recommended version and/or errors

Examples

# Generate a basic changelog
./bin/changelog-generator ./v1.0.0 ./v1.1.0

# Specify current version and output file
./bin/changelog-generator ./v1.0.0 ./v1.1.0 -v 1.0.0 -o CHANGELOG.md

# Ignore specific folders
./bin/changelog-generator ./v1.0.0 ./v1.1.0 -i "*/vendor/*" -i "*/tests/*" -i "*/examples/*"

# Generate a JSON report
./bin/changelog-generator ./v1.0.0 ./v1.1.0 -f json -o report.json

# Preview without writing to file
./bin/changelog-generator ./v1.0.0 ./v1.1.0 --dry-run

# Use strict SemVer for pre-1.0.0 versions
./bin/changelog-generator ./v0.1.0 ./v0.2.0 --current-version 0.1.0 --strict-semver

SemVer Rules

Major Changes (Breaking Changes)

• Removed methods/functions
• Incompatible signatures (required parameters added, types changed)
• Removed classes/interfaces
• Modified/removed constants
• Restrictive visibility changes

Minor Changes (Backward Compatible)

• New methods/functions/classes
• Optional parameters added
• New implemented interfaces
• New constants

Patch Changes

• PHPDoc modifications without signature impact
• Internal changes without public API impact

Pre-1.0.0 SemVer Behavior

By default, for versions before 1.0.0 (e.g., 0.x.y), this tool follows a relaxed SemVer approach:

• Breaking changes (normally major) are treated as minor changes
• New features remain minor changes
• Bug fixes remain patch changes

This reflects the common practice that pre-1.0.0 versions are in development and breaking changes are expected.

Strict SemVer Mode

Use the --strict-semver flag to enforce standard SemVer rules even for pre-1.0.0 versions:

# Relaxed mode (default): 0.1.0 + breaking changes = 0.2.0
./bin/changelog-generator ./v0.1.0 ./v0.2.0 --current-version 0.1.0

# Strict mode: 0.1.0 + breaking changes = 1.0.0
./bin/changelog-generator ./v0.1.0 ./v0.2.0 --current-version 0.1.0 --strict-semver

PHPDoc Analysis

The tool prioritizes native PHP signature analysis but uses PHPDoc as fallback:

• If PHP signature is typed → uses the signature
• If only PHPDoc is typed → uses PHPDoc
• In case of conflict → logs a warning and uses the signature

Architecture

src/
├── Model/          # Data models (ApiElement, ApiChange, etc.)
├── Parser/         # PHP parser (nikic/php-parser + PHPDoc)
├── Differ/         # Version comparator
├── Analyzer/       # SemVer analysis
├── Generator/      # Changelog generator
└── Console/        # CLI interface

Development

Tests

composer test

Code standards

composer cs-check  # Check
composer cs-fix    # Fix

Static analysis

composer phpstan

License

MIT