Code Smell 165 - Empty Exception Blocks

On Error resume next was the first thing I learned in my first job

TL;DR: Don't avoid exceptions. Handle Them.

Problems

Fail Fast Principle Violation

Solutions

Catch the exception and deal with it explicitly

Context

On early programming days, we privileged the systems running before error handling.

We have evolved.

Sample Code

Wrong

# bad
import logging

def send_email(): 
  print("Sending email") 
  raise ConnectionError("Oops")

try:
  send_email() 
except: 
  # AVOID THIS
pass

Right

import logging

logger logging.getLogger(__name___)
try:
  send_email()
except ConnectionError as exc:
  logger.error(f"Cannot send email {exc}")

Detection

[X] Automatic

Many linters warn us on empty exception blocks

Exceptions

If we need to skip and ignore the exception, we should document it explicitly.

Conclusion

Prepare to deal with the errors.

Even if you decide to do nothing, you should be explicit with this decision.

Relations

Code Smell 132 - Exception Try Too Broad

Maxi Contieri ・ May 18 '22

#python #programming #cleancode #webdev

More Info

Fail Fast

Maxi Contieri ・ Dec 6 '20

#codenewbie #programming #webdev #oop

On Error Resume Next Package

Disclaimer

Code Smells are just my opinion.

Credits

Photo by James Best on Unsplash

Thank you @Jan Giacomelli

Optimization hinders evolution. Everything should be built top-down, except the first time. Simplicity does not precede complexity, but follows it.

Alan Perlis

Software Engineering Great Quotes

Maxi Contieri ・ Dec 28 '20

#codenewbie #programming #quotes #software

This article is part of the CodeSmell Series.

How to Find the Stinky parts of your Code

Maxi Contieri ・ May 21 '21

#codenewbie #tutorial #codequality #beginners