ExtendedClassIndex

Whether anything in the codebase extends a given class.

Adding a constructor parameter to a class that others extend is not safe, and a dry run against the reference application’s Api module is what proved it. ApiBaseAction is concrete, has 58 subclasses, and six of them already declared their own constructor. Injecting into the base gave it __construct(RequestState, User); no subclass forwards to it, so every one of them would have left $this->user uninitialized — and ApiBaseAction::validatePermissions(), which every API action calls, reads exactly that. A whole module fatalling at runtime, produced by a migration tool, in code that had just been reviewed.

The reverse is no better: appending a required parameter to a base class’s existing constructor breaks every subclass that forwards with the old arity. And which of the two happens depends on the order Rector reaches the files in, so it is not even deterministic.

Rector 2.6 has no subclass enumeration — FamilyRelationsAnalyzer walks ancestors, not descendants — so this indexes the codebase itself, once per process.

Deliberately approximate, in the safe direction

Matching is on the short name after extends, not on a resolved fully-qualified name. Resolving one properly means tracking imports and aliases per file, which is where a scanner like this gets subtly wrong. A short-name match can therefore report “extended” for a same-named class in an unrelated namespace — and the consequence of that is a rule declining a site it could have rewritten, which lands in the residue report for a human to look at. The consequence of the opposite error is the module-wide fatal described above. So the approximation only ever costs coverage, never correctness.

Synopsis

final class ExtendedClassIndex

Since	4.0.0
Source	NodeAnalyzer/ExtendedClassIndex.php

Constructor

__construct()

public function __construct(?array<int, string> $roots = null): mixed

Directories to scan. Null asks Composer, which is what the container does; a caller that knows its own source roots — a test — passes them instead of arranging an autoloader to be discovered.

Parameter	Type	Description
$roots	?``array``<``int``, ``string``>	Directories to scan. Null asks Composer, which is what the container does; a caller that knows its own source roots — a test — passes them instead of arranging an autoloader to be discovered.

Returns mixed

Methods

Method	Description
isExtended(string $className): bool	Whether any class in the codebase extends this one.

isExtended()

public function isExtended(string $className): bool

Whether any class in the codebase extends this one.

Parameter	Type	Description
$className	string

Returns bool