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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

        Loops and recursions should not be infinite

        intentionality - logical
        reliability
        Bug
        • suspicious

        Why is this an issue?

        How can I fix it?

        More Info

        Having an infinite loop or recursion will lead to a program failure or a program never finishing the execution.

        public int Sum()
        {
            var i = 0;
            var result = 0;
            while (true) // Noncompliant: the program will never stop
            {
                result += i;
                i++;
            }
            return result;
        }
        

        This can happen in multiple scenarios.

        Loop statements

        while and for loops with no break or return statements that have exit conditions which are always false will be indefinitely executed.

        "goto" statements

        goto statement with nothing that stops it from being executed over and over again will prevent the program from the completion.

        Recursion

        When a recursive method call chain lacks an exit condition, the call stack will reach its limit and the program will crash due to a StackOverflowException.

        int Pow(int num, int exponent)
        {
          return num * Pow(num, exponent - 1); // Noncompliant: no condition under which Pow isn't re-called
        }
        

        In this example, Pow will keep calling Pow with exponent - 1 forever, until the program crashes with a StackOverflowException.

        Recursion provides some benefits.

        • Simplified code: recursion can often lead to more concise and elegant code by breaking down complex problems into smaller, more manageable parts.
        • Improved code readability: compared to iterative solutions, recursive solutions can be easier to understand and reason about.

        However, it has disadvantages as well.

        • Stack overflow: Recursive functions can lead to stack overflow if the recursion is too deep, potentially causing the program to crash.
        • Performance overhead: Recursive function calls can lead to poor performance due to the need to push and pop stack frames, making them potentially slower than iterative solutions.
        • Difficulty in debugging: Debugging recursive code can be challenging, as multiple recursive calls can make it harder to track the flow of execution and identify logical errors.
        • Space complexity: Recursive algorithms may require more memory compared to iterative approaches, as each recursive call adds a new frame to the call stack.
        • Lack of control: Recursion can sometimes lead to infinite loops or unexpected behavior if not properly implemented or terminated, making it crucial to have proper base cases and exit conditions.
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