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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: 14 rules found
bad-practice
    Impact
      Clean code attribute
        1. "ExcludeFromCodeCoverage" attributes should include a justification

           Code Smell
        2. Client instances should not be recreated on each Azure Function invocation

           Code Smell
        3. Azure Functions should be stateless

           Code Smell
        4. "is" should not be used with "this"

           Code Smell
        5. "Thread.Sleep" should not be used in tests

           Code Smell
        6. "nameof" should be used

           Code Smell
        7. Formatting SQL queries is security-sensitive

           Security Hotspot
        8. Loops with at most one iteration should be refactored

           Bug
        9. Tests should not be ignored

           Code Smell
        10. "switch" statements should have at least 3 "case" clauses

           Code Smell
        11. "GC.Collect" should not be called

           Code Smell
        12. Nested code blocks should not be used

           Code Smell
        13. "Obsolete" attributes should include explanations

           Code Smell
        14. Standard outputs should not be used directly to log anything

           Code Smell

        "ExcludeFromCodeCoverage" attributes should include a justification

        intentionality - clear
        maintainability
        Code Smell
        • bad-practice

        Why is this an issue?

        More Info

        The ExcludeFromCodeCoverageAttribute is used to exclude portions of code from code coverage reporting. It is a bad practice to retain code that is not covered by unit tests. In .Net 5, the Justification property was added to the ExcludeFromCodeCoverageAttribute as an opportunity to document the rationale for the exclusion. This rule raises an issue when no such justification is given.

        Noncompliant code example

        public struct Coordinates
        {
            public int X { get; }
            public int Y { get; }
        
            [ExcludeFromCodeCoverage] // Noncompliant
            public override bool Equals(object obj) => obj is Coordinates coordinates && X == coordinates.X && Y == coordinates.Y;
        
            [ExcludeFromCodeCoverage] // Noncompliant
            public override int GetHashCode()
            {
                var hashCode = 1861411795;
                hashCode = hashCode * -1521134295 + X.GetHashCode();
                hashCode = hashCode * -1521134295 + Y.GetHashCode();
                return hashCode;
            }
        }
        

        Compliant solution

        public struct Coordinates
        {
            public int X { get; }
            public int Y { get; }
        
            [ExcludeFromCodeCoverage(Justification = "Code generated by Visual Studio refactoring")] // Compliant
            public override bool Equals(object obj) => obj is Coordinates coordinates && X == coordinates.X && Y == coordinates.Y;
        
            [ExcludeFromCodeCoverage(Justification = "Code generated by Visual Studio refactoring")] // Compliant
            public override int GetHashCode()
            {
                var hashCode = 1861411795;
                hashCode = hashCode * -1521134295 + X.GetHashCode();
                hashCode = hashCode * -1521134295 + Y.GetHashCode();
                return hashCode;
            }
        }
        
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