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C#

C# static code analysis

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

  • All rules 493
  • Vulnerability46
  • Bug88
  • Security Hotspot24
  • Code Smell335

  • Quick Fix 61
Filtered: 36 rules found
suspicious
    Impact
      Clean code attribute
        1. Parameter names should match base declaration and other partial definitions

           Code Smell
        2. Methods should not have identical implementations

           Code Smell
        3. Collection elements should not be replaced unconditionally

           Bug
        4. A conditionally executed single line should be denoted by indentation

           Code Smell
        5. Conditionals should start on new lines

           Code Smell
        6. Number patterns should be regular

           Code Smell
        7. "out" and "ref" parameters should not be used

           Code Smell
        8. Unassigned members should be removed

           Code Smell
        9. "[DefaultValue]" should not be used when "[DefaultParameterValue]" is meant

           Code Smell
        10. Type should not be examined on "System.Type" instances

           Code Smell
        11. Assertion arguments should be passed in the correct order

           Code Smell
        12. "this" should not be exposed from constructors

           Code Smell
        13. Implementations should be provided for "partial" methods

           Code Smell
        14. Caller information arguments should not be provided explicitly

           Code Smell
        15. "Explicit" conversions of "foreach" loops should not be used

           Code Smell
        16. "ConfigureAwait(false)" should be used

           Code Smell
        17. Sequential tests should not check the same condition

           Code Smell
        18. "IndexOf" checks should not be for positive numbers

           Code Smell
        19. Boolean expressions should not be gratuitous

           Code Smell
        20. Conditionally executed code should be reachable

           Bug
        21. Generic exceptions should not be ignored

           Code Smell
        22. Unnecessary bit operations should not be performed

           Code Smell
        23. Methods without side effects should not have their return values ignored

           Bug
        24. Unnecessary mathematical comparisons should not be made

           Code Smell
        25. Modulus results should not be checked for direct equality

           Code Smell
        26. Loops and recursions should not be infinite

           Bug
        27. Invalid casts should be avoided

           Code Smell
        28. Two branches in a conditional structure should not have exactly the same implementation

           Code Smell
        29. Identical expressions should not be used on both sides of operators

           Bug
        30. "==" should not be used when "Equals" is overridden

           Code Smell
        31. Methods should not be empty

           Code Smell
        32. Exceptions should not be thrown in finally blocks

           Code Smell
        33. Exit methods should not be called

           Code Smell
        34. Assignments should not be made from within sub-expressions

           Code Smell
        35. Local variables should not shadow class fields or properties

           Code Smell
        36. Nested blocks of code should not be left empty

           Code Smell

        Boolean expressions should not be gratuitous

        intentionality - logical
        maintainability
        Code Smell
        • cwe
        • suspicious
        • redundant
        • symbolic-execution

        Gratuitous boolean expressions are conditions that do not change the evaluation of a program. This issue can indicate logical errors and affect the correctness of an application, as well as its maintainability.

        Why is this an issue?

        How can I fix it?

        More Info

        Control flow constructs like if-statements allow the programmer to direct the flow of a program depending on a boolean expression. However, if the condition is always true or always false, only one of the branches will ever be executed. In that case, the control flow construct and the condition no longer serve a purpose; they become gratuitous.

        What is the potential impact?

        The presence of gratuitous conditions can indicate a logical error. For example, the programmer intended to have the program branch into different paths but made a mistake when formulating the branching condition. In this case, this issue might result in a bug and thus affect the reliability of the application. For instance, it might lead to the computation of incorrect results.

        Additionally, gratuitous conditions and control flow constructs introduce unnecessary complexity. The source code becomes harder to understand, and thus, the application becomes more difficult to maintain.

        This rule looks for operands of a boolean expression never changing the result of the expression. It also applies to the null coalescing operator when one of the operands always evaluates to null.

        string d = null;
        var v1 = d ?? "value";      // Noncompliant
        

        Exceptions

        This rule will not raise an issue in either of these cases:

        • When the condition is a single const bool
          const bool debug = false;
          //...
          if (debug)                  // Compliant
          {
            // Print something
          }
          
        • When the condition is the literal true or false.

        In these cases, it is obvious the code is as intended.

          Available In:
        • SonarQube CloudDetect issues in your GitHub, Azure DevOps Services, Bitbucket Cloud, GitLab repositories
        • SonarQube ServerAnalyze code in your
          on-premise CI
          Developer Edition
          Available Since
          9.1

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