1.2.1338. Use Positive Condition

Whenever possible, use a positive condition.

Positive conditions are easier to understand, and lead to less understanding problems. Negative conditions are not reported when else is not present.

<?php

// This is a positive condition
if ($a == 'b') {
    doSomething();
} else {
    doSomethingElse();
}

if (!empty($a)) {
    doSomething();
} else {
    doSomethingElse();
}

// This is a negative condition
if ($a == 'b') {
    doSomethingElse();
} else {
    doSomething();
}

// No need to force $a == 'b' with empty else
if ($a != 'b') {
    doSomethingElse();
}

?>

See also Double negatives should not not be avoided and How To Write Conditional Statements in PHP.

1.2.1338.1. Suggestions

• Invert the code in the if branches, and the condition

1.2.1338.2. Specs

Short name	Structures/UsePositiveCondition
Rulesets	All, Analyze
Exakat since	0.8.6
PHP Version	All
Severity	Minor
Time To Fix	Quick (30 mins)
Precision	Very high
Examples	SPIP, ExpressionEngine
Available in	Entreprise Edition, Exakat Cloud