Your code smells because there are likely many instances where it could be edited or improved. Most of these smells are just hints of something that might be wrong. Therefore, they are not required to be fixed per se… (You should look into it, though.) Previous Code Smells You can find all the previous code smells (Part I - XLIV) . here Let's continue... Code Smell 221 - Missing Break in Switch You abuse cases in switches and make subtle mistakes TL;DR: Cases are GOTOs, but you might be missing them Problems Hidden defects Readability Solutions Add the missing break Convert the switch into a polymorphic hierarchy the default switch Remove Context In a switch statement, when a match is found in a particular case, the code execution will start from that case and continue executing all subsequent cases until a break statement is encountered or the switch block ends. This behavior is called "fall-through." Forgetting a clause will continue with the following case. break This is similar to a very that implied an urgent release. serious vulnerability Sample Code Wrong switch (number) {
      case 1:
          printf("Number is 1.\n");
          break;
      case 2:
          printf("Number is 2.\n"); 
          // Missing break
      case 3:
          // Case 2 will continue here
          printf("Number is 3.\n"); 
          break;
      default:
          printf("Number is not 1, 2, or 3.\n");
  }

// If the number is 2 this will output numbers 2 and 3 Right switch (number) {
      case 1:
          printf("Number is 1.\n");
          break;
      case 2:
          printf("Number is 2.\n"); 
          break; // Added 'break' to prevent fall-through
      case 3:
          printf("Number is 3.\n"); 
          break;
      default:
          printf("Number is not 1, 2, or 3.\n");
  }

// This is correct even though switches AND defaults
// Are other code smells Detection Automatic [x] Many and also ChatGPT detect this smell. linters Tags IFs Conclusion Using switches and causes is problematic, your need to use higher-level sentences. Relations Code Smell 110 - Switches With Defaults Code Smell 36 - Switch/case/elseif/else/if statements Code Smell 100 - GoTo More Info Sonar Source Common Weakness Enumeration How to Get Rid of Annoying IFs Forever Apple's Security Defect Disclaimer: Code Smells are my . opinion Credits: Photo by on Nikola Johnny Mirkovic Unsplash I am not terribly dogmatical about the goto statement. I have the uncomfortable feeling that others are making a religion out of it, as if the conceptual problems of programming could be solved by a single trick, by a simple form of coding discipline! - Edsger Dijkstra Code Smell 222 - Comma Operator Don't abuse this fancy operator TL;DR: Use comma operator just for loops Problems Readability Hidden Defects Solutions Avoid operator usage Prefer operator foreach Break the sentences Context In JavaScript, the comma operator allows you to evaluate multiple expressions sequentially and return the value of the last expression. It's denoted by a comma and separates multiple expressions within a larger expression. Each expression is evaluated in order from left to right, and the final value of the entire comma-separated expression is the value of the last expression. Sample Code Wrong const gravitationalConstant = 6.67430e-11;

const massBlackHole1 = 1.5e31;  // Mass of the first black hole in kg
const massBlackHole2 = 2.2e32;  // Mass of the second black hole in kg
const distanceBlackHoles = 5.7e20;  // Distance between black holes in meters

var force = (distanceSquared = distanceBlackHoles * distanceBlackHoles,
             (gravitationalConstant * massBlackHole1 * massBlackHole2) /
             distanceSquared);
// Two operations in a single statement with comma operator Right function calculateGravitationalForce(mass1, mass2, distance) {
  const gravitationalConstant = 6.67430e-11;
  return (gravitationalConstant * mass1 * mass2) / (distance * distance);  
}

const massBlackHole1 = 1.5e31;  // Mass of the first black hole in kg
const massBlackHole2 = 2.2e32;  // Mass of the second black hole in kg
const distanceBlackHoles = 5.7e20;  // Distance between black holes in meters

const force = calculateGravitationalForce(
  massBlackHole1,
  massBlackHole2,
  distanceBlackHoles
);
// Notice force is calculated with a separate function Detection Automatic [x] Many can detect this problem. linters Exceptions For loops are a valid exception dough they might lead you to another code smell Tags Readability Conclusion This valid operator was designed to shorten but is now sometimes abused. for loops Relations Code Smell 53 - Explicit Iteration Credits Photo by on Stephen Hickman Unsplash My computer's so fast it finishes an infinite loop in 5 minutes. - Chisel Wright Code Smell 223 - Racial Naming Software evolves, and so does culture. TL;DR: Avoid old terms like , , , etc. whitelists blacklists master Problems Racial Connotations Exclusionary Language Diverse Perspectives Solutions Use alternative terminology Context Language evolves, and technical terms should follow it. You can change racial names with alternative terminology: Allowlist: Replace "whitelist" with "allowlist." This term maintains the intended meaning without racial connotations. Denylist: Substitute "blacklist" with "denylist." This term conveys the same concept without perpetuating negative racial associations. Permit List and Block List: Another option is to use "permit list" in place of "whitelist" and "block list" instead of "blacklist." Main branches: You can replace "master" with "main". Master/Slave: You can replace them with Primary/Replica/Mirror etc. Sample Code Wrong val whitelist = listOf("Barbie", "Ken")

val blacklist = listOf("Midge")

val gitCommand = "git pull origin master"

val process = Runtime.getRuntime().exec(gitCommand) Right val allowlist = listOf("Barbie", "Ken")

val denylist = listOf("Midge")

val gitCommand = "git pull origin main"

val process = Runtime.getRuntime().exec(gitCommand) Detection Semi-Automatic [x] You can set up a denylist (not a blacklist) of terms you need to double-check for accuracy. Exceptions References to old manuals Tags Naming Conclusion Just as we refactor code to enhance its quality, we should also refactor our language and terminology to promote inclusivity and diversity. By eliminating racially insensitive terms like "whitelist" and "blacklist" in favor of more inclusive alternatives, we contribute to a more equitable and welcoming tech industry. Let's embrace change and create a coding environment where everyone feels valued, regardless of their background or ethnicity. Relations Code Smell 105 - Comedian Methods More Info Prevalence of racist language in discussions of predatory publishing Wikipedia Rename master to main Credits: Photo by on Aarón Blanco Tejedor Unsplash An ultimate joint challenge for the biological and the computational sciences is the understanding of the mechanisms of the human brain, and its relationship with the human mind. - Tony Hoare Code Smell 224 - Deodorant Comments You use nice words to excuse bad code TL;DR: Don't excuse bad code. Write a clean one! Problems Readability Solutions Rewrite the code and delete the comment Context The term comes from Martin Fowler's book "Refactoring: Improving the Design of Existing Code" Sample Code Wrong # This is a function that adds two numbers
def s(a, b):
    # Now you are going to add a and b
    res = a + b
    # And return the result
    return res Right def sum(adder, anotherAdder):
    
    return adder + anotherAdder If you ask ChatGPT to improve this version it will actually worsen it: def calculate_sum(number1, number2):
    # Calculate the sum of two numbers
    result = number1 + number2
    return result

# In this improved version:
#
# The function name calculate_sum is more descriptive than sum, 
# making it clear that this function calculates the sum of two numbers.
# (Wrong) it is more imperative and mistakes the 'what' with the 'how'
#
# The parameter names number1 and number2 are more meaningful 
# than adder and anotherAdder, helping to indicate the purpose of each parameter.
# (wrong) They indicate type instead of role
#
# The comment # Calculate the sum of two numbers provides a clear 
# and concise explanation of what the function does, 
# making it easier for someone reading the code to understand its purpose.    
# (wrong) in fact, it is an example of deodorant and useless comment Detection Semi-Automatic [x] Most comments are code smells. You can remove deodorant comments and improve the code. Exceptions Comments should only be used to describe important design decisions. Tags Comments Conclusion Remove any meaningless comment you find in your code. Relations Code Smell 151 - Commented Code Code Smell 183 - Obsolete Comments Code Smell 146 - Getter Comments Code Smell 05 - Comment Abusers Refactoring 011 - Replace Comments with Tests More Info Clean Code In C# Credits: Photo by on Ana Essentiels Unsplash The reason we mention comments here is that comments often are used as a deodorant. It's surprising how often you look at thickly commented code and notice that the comments are there because the code is bad. - Martin Fowler Code Smell 225 - Pass by Reference Pass by copy, pass by reference. which is better? TL;DR: Beware of passing arguments by reference Problems Unexpected Results Side Effects Readability Broken Encapsulation Solutions Pass arguments by copying even large objects. Don't make . premature optimizations Declare variables as constants the code Refactor Make objects to avoid accidental changes immutable 5 Use Pure Functions Context A call-by-reference language like C# or PHP makes it more difficult for a programmer to track the effects of a function call and may introduce subtle bugs. This is a very old technique present in low-level languages to favor performance and avoid the cost of copying large structures. Some languages like Go use semantics. When you pass arguments to a function, copies are made. However, when you pass a pointer to an object, you can modify the original object within the function. This is another code smell. On the contrary, functional languages forbid this mechanism completely. pass-by-value Sample Code Wrong using System;
 
namespace Example
{
     class Betelgeuse
     {
         static void Main(string[] args)
         {
             double starSize = 100.0;
             Console.WriteLine("star size: {0}", starSize);
             // star size: 100
             double supernovaSize = SimulateFinalSize(ref starSize);
             // Notice 'ref' modifier
             Console.WriteLine("supernova size: {0}", supernovaSize); 
             // supernova size: 10000
             Console.WriteLine("original star size after: {0}", starSize);
             // original star size after: 10000
             // WRONG: It should not be affected
         }
         public static double SimulateFinalSize(ref double size)
         {
             // Notice 'ref' modifier
             // Oversimplification
             // You should use Sedov-Taylor solution
              size = size * 100;
              return size;
         }
     }
} Right using System;
 
namespace Example
{
     class Betelgeuse
     {
         static void Main(string[] args)
         {
             const double starSize = 100.0; 
             // The const modifier warns the compiler
             Console.WriteLine("star size: {0}", starSize);
             // star size: 100
             double supernovaSize = SimulateFinalSize(starSize);
             // Notice 'ref' is omitted
             Console.WriteLine("supernova size: {0}", supernovaSize);
             // supernova size: 10000
             Console.WriteLine("original star size after: {0}", starSize);
             // original star size after: 100
             // It remains at the original value
         }
         public static double SimulateFinalSize(double size)
         {
             // Notice 'ref' is omitted
             // Oversimplification
             // You should use Sedov-Taylor solution
              size = size * 100;
              return size;
         }
     }
} Detection Semi-Automatic [x] You can use many linters to warn with arguments passed by reference Tags Readability Conclusion Passing objects by reference can lead to unexpected side effects if the function modifies the object in a way that wasn't anticipated by the caller. You should use copy by value instead. Relations Code Smell 116 - Variables Declared With 'var' Code Smell 176 - Changes in Essence Code Smell 209 - Side Effects More Info Modifiyng Method Parameter Wikipedia Credits: Photo by on Quino Al Unsplash Make it correct, make it clear, make it concise, make it fast. In that order. Wes Dyer Next week, 5 more smells

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