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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

        "Thread.Sleep" should not be used in tests

        intentionality - complete
        maintainability
        Code Smell
        • tests
        • bad-practice

        Why is this an issue?

        More Info

        Using Thread.Sleep in a test might introduce unpredictable and inconsistent results depending on the environment. Furthermore, it will block the thread, which means the system resources are not being fully used.

        [TestMethod]
        public void SomeTest()
        {
            Thread.Sleep(500); // Noncompliant
            // assertions...
        }
        

        An alternative is a task-based asynchronous approach, using async and await.

        More specifically the Task.Delay method should be used, because of the following advantages:

        • It is asynchronous: The thread will not be blocked, but instead will be reused by other operations
        • It is more precise in timing the delay than Thread.Sleep
        • It can be canceled and continued, which gives more flexibility and control in the timing of your code
        [TestMethod]
        public async Task SomeTest()
        {
            await Task.Delay(500);
            // assertions...
        }
        

        Another scenario is when some data might need to be mocked using Moq, and a delay needs to be introduced:

        [TestMethod]
        public void UserService_Test()
        {
            var userService = new Mock<UserService>();
            var expected = new User();
        
            userService
                .Setup(m => m.GetUserById(42))
                .Returns(() =>
                {
                    Thread.Sleep(500); // Noncompliant
                    return Task.FromResult(expected);
                });
        
            // assertions...
        }
        

        An alternative to Thread.Sleep while mocking with Moq is to use ReturnsAsync and pass the amount of time to delay there:

        [TestMethod]
        public void UserService_Test()
        {
            var userService = new Mock<UserService>();
            var expected = new User();
        
            userService
                .Setup(m => m.GetUserById(42))
                .ReturnsAsync(expected, TimeSpan.FromMilliseconds(500));
        
            // assertions...
        }
        
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