Whenever you cook a portion of food or writing an article, there’s a smell existed. To determine the smell is good or bad it depends on the characteristic of the food/article. For example, an excellent article optimized with fewer errors in punctuation, grammar and well-structured. 

The same, the code smells are also referring to the characteristic of the source code from the software. To determine the code are in good smell or not, you may look into the different characteristics of the code smell below.

Bad smell

  • Duplicated code
  • Long Parameter List
  • Long method
  • Complex conditional statement
  • Primitive obsession
  • Lazy classes
  • Large classes
  • Oddball solutions
  • Moreover, you can refer to the link below

http://www.industriallogic.com/wp-content/uploads/2005/09/smellstorefactorings.pdf