Question 1

How do I exclude test code from dead code detection in PHPStan?

Accepted Answer

Enable the tests usage excluder in your phpstan.neon by setting shipmonkDeadCode.usageExcluders.tests.enabled to true. It auto-detects dev paths from composer.json or lets you specify them manually, so code only used in tests won't mark production members as alive.

Question 2

Dead code detector vs PHPStan's native unused code detection: which is better?

Accepted Answer

Dead code detector is superior for complex applications because it understands framework patterns and transitive dependencies, reducing false positives. PHPStan's native checks are more generic and may miss dead cycles or framework-specific usages.

Question 3

How to add custom detection for serialized properties in API responses?

Accepted Answer

Implement a ReflectionBasedMemberUsageProvider to mark properties as used when their class implements an interface like ApiOutput, or use an AST-based provider for more complex logic. The README provides code examples for both approaches.

Question 4

Does dead code detector work with Laravel Eloquent model methods?

Accepted Answer

Yes, it supports Laravel Eloquent out-of-the-box, detecting used methods like relationships, accessors, and scopes. It automatically enables Laravel usage providers when Laravel dependencies are found in composer.json.

Question 5

Can I automatically remove dead code found by this tool?

Accepted Answer

Yes, run PHPStan with --error-format removeDeadCode to automatically delete confirmed dead code. It outputs diffs showing changes, but be cautious as it leaves test usages intact if the tests excluder is enabled.

Question 6

What are common false positives in Symfony apps with this detector?

Accepted Answer

False positives can occur with constructors if services are created magically without the Dependency Injection Container, or with interface methods only called on implementors. The README suggests ignoring constructors or implementing custom providers to mitigate this.

Dead Code Detector

What is Dead Code Detector?

Overview

Use Cases

Best For

Related Projects

Found a gem we're missing?

Not Ideal For

Pros & Cons

Pros

Cons

Frequently Asked Questions