rspec/rules/S5996/rule.adoc

In regular expressions the boundaries ``++^++`` and ``++\A++`` can only match at the beginning of the input (or, in case of ``++^++`` in combination with the ``++MULTILINE++`` flag, the beginning of the line) and ``++$++``, ``++\Z++`` and ``++\z++`` only at the end.

These patterns can be misused, by accidentally switching ``++^++`` and ``++$++`` for example, to create a pattern that can never match.


== Noncompliant Code Example

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// This can never match because $ and ^ have been switched around
Pattern.compile("$[a-z]+^"); // Noncompliant
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== Compliant Solution

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Pattern.compile("^[a-z]+$");
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