Uppercase Keyword

ID

php.keywords_case

Severity

info

Remediation Complexity

trivial

Remediation Risk

low

Remediation Effort

low

Resource

Code Smell

Language

Php

Tags

code_smell, naming

Description

Reports PHP keywords — and the constants true, false and null — written in anything other than lower case, such as IF, Function or TRUE. The recognised keyword set is configurable through the keywords property.

Rationale

PHP is case-insensitive for its keywords and for the true, false and null constants, so IF, If and if all compile. Mixing cases hurts readability: the eye uses the consistent lower case of keywords to separate language scaffolding from the program’s own identifiers, and that cue is lost when the casing wanders. The community style guides require keywords and these constants to be written in lower case.

<?php
class Widget
{
    public function render(int $n): string
    {
        IF ($n > 0) {          // FLAW - keyword IF should be lower case
            return "positive"; // OK - keyword is already lower case
        }
        return "non-positive";
    }
}

Remediation

Rewrite the flagged keyword in lower case (IF becomes if, Function becomes function, TRUE becomes true).

References