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PHP

PHP static code analysis

Unique rules to find Bugs, Vulnerabilities, Security Hotspots, and Code Smells in your PHP code

  • All rules 273
  • Vulnerability42
  • Bug51
  • Security Hotspot34
  • Code Smell146
Filtered: 1 rule found
symbolic-execution
    Impact
      Clean code attribute
        1. Variables should be initialized before use

           Bug

        Variables should be initialized before use

        intentionality - clear
        reliability
        Bug
        • cwe
        • symbolic-execution

        Why is this an issue?

        More Info

        In PHP it is not required to initialize variables before their usage. However, using uninitialized variables is considered bad practice and should be avoided because of the following reasons:

        • The value and type of uninitialized variables depend on the context of their first usage. It is better to be explicit about those to avoid confusion.
        • The interpreter raises a warning or a notice in many cases.

        Noncompliant code example

        <?php
        
        function getText(array $lines): string {
            foreach ($lines as $line) {
                $text .= $line;
            }
        
            return $text;
        }
        

        Compliant solution

        <?php
        
        function getText(array $lines): string {
            $text = "";
        
            foreach ($lines as $line) {
                $text .= $line;
            }
        
            return $text;
        }
        
          Available In:
        • SonarQube IdeCatch issues on the fly,
          in your IDE
        • SonarQube CloudDetect issues in your GitHub, Azure DevOps Services, Bitbucket Cloud, GitLab repositories
        • SonarQube Community BuildAnalyze code in your
          on-premise CI
          Available Since
          9.1
        • SonarQube ServerAnalyze code in your
          on-premise CI
          Developer Edition
          Available Since
          9.1

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