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30 lines
645 B
Markdown
30 lines
645 B
Markdown
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# RiskyTruthyFalsyComparison
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Emitted when comparing a value with multiple types that can both contain truthy and falsy values.
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```php
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<?php
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/**
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* @param array|null $arg
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* @return void
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*/
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function foo($arg) {
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if ($arg) {
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// this is risky, bc the empty array and null case are handled together
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}
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if (!$arg) {
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// this is risky, bc the empty array and null case are handled together
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}
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}
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```
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## Why this is bad
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The truthy/falsy type of one variable is often forgotten and not handled explicitly causing hard to track down errors.
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## How to fix
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Explicitly validate the variable with strict comparison.
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