38 lines
1.3 KiB
Plaintext
38 lines
1.3 KiB
Plaintext
== Why is this an issue?
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An `preg_replace` call always performs an evaluation of the first argument as a regular expression, even if no regular expression features were used. This has a significant performance cost and therefore should be used with care.
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When `preg_replace` is used, the first argument should be a real regular expression. If it's not the case, `str_replace` does exactly the same thing as `preg_replace` without the performance drawback of the regex.
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This rule raises an issue for each `preg_replace` used with a simple string as first argument which doesn't contains special regex character or pattern.
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=== Noncompliant code example
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[source,php]
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----
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$str = "Bob is a Bird... Bob is a Plane... Bob is Superman!";
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$changed = preg_replace("/Bob is/", "It's", $str); // Noncompliant
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$changed = preg_replace("/\.\.\./", ";", $changed); // Noncompliant
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----
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=== Compliant solution
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[source,php]
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----
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$str = "Bob is a Bird... Bob is a Plane... Bob is Superman!";
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$changed = str_replace("Bob is", "It's", $str);
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$changed = str_replace("...", ";", $changed);
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----
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Or, with a regex:
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[source,php]
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----
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$str = "Bob is a Bird... Bob is a Plane... Bob is Superman!";
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$changed = preg_replace("/\w*\sis/", "It's", $str);
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$changed = preg_replace("/\.{3}/", ";", $changed);
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----
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