Field Name Matches Class

ID

php.field_name_matches_class

Severity

info

Remediation Complexity

trivial

Remediation Risk

low

Remediation Effort

low

Resource

Code Smell

Language

Php

Tags

code_smell, naming

Description

Reports a property that is both named like its declaring class and declared with that class as its type — a genuinely self-typed field. Both regular and constructor-promoted properties are checked; the type comparison is case-insensitive and ignores a leading ? or \.

Rationale

A property typed as its own class and named after it (class Node { private Node $node; }) blurs the distinction between the type and one of its values and usually signals a confused design. A mere name coincidence is not a defect, so the rule requires the declared type to match: a principal-value field such as class State { private $state; } or a differently-typed field such as class Json { private string $json; } is idiomatic and is left alone.

<?php
class Node
{
    private Node $node;       // FLAW — self-typed field named like the class
    private string $label;    // OK — distinct name
}

class State
{
    private $state;           // OK — principal-value field, no type
}

class Json
{
    private string $json;     // OK — name matches class but type is string
}

Remediation

Rename the property to describe the value it holds rather than the type that owns it, for example $next, $parent, or $child.

References