If you've ever debugged a web application, you know that it can sometimes be a painful process. But don't worry! Here are some tips to help improve your debugging skills so that you can debug faster and more efficiently.
Turn on Console.
You're not alone if you've never heard of the browser console. It's one of those things that only people who spend a lot of time with web development tend to use, because it's incredibly useful in debugging code.
The browser console is available in Chrome, Firefox, Safari and Edge (Internet Explorer doesn't have a built-in console). The feature looks different from one browser to another, but generally it's located under Developer Tools or some variation of that name.
You can also access your developer tools with these keyboard shortcuts:
Chrome: Ctrl+Shift+J
Safari: Cmd+Option+I (Mac) or Ctrl + Alt + I (Windows/Linux)
Read the error message carefully.
When you encounter an error, the first step is to read the message carefully. The information in this message is there to help you figure out what went wrong and how to fix it. But sometimes, error messages can be misleading or hard to understand. Let's look at some examples:
"Cannot fetch URL" - This one should be pretty obvious—you can't fetch any URLs because your computer doesn't have internet access! You probably want to check that first before trying anything else.
"no debug information available" - This usually indicates that there's something wrong with your development environment (e.g., a missing library, broken connection between files), but also tells us that it's not possible for us as humans to tell what exactly happened by looking at this message alone (so perhaps it would've been better if they'd said "Please check all of your libraries and make sure they're linked correctly").
Read the stack trace carefully.
The stack trace is the trail that traces your code's execution. It contains all of the information about which functions were called, how many times they were called and what values each function passed to others.
It's important for you to be able to read a stack trace when debugging because it will help you find out where in your code something went wrong (and if something didn't work as expected).
Stack traces can be very long and contain a lot of information: if one line looks like this:
Read the stack trace upside down.
Stack traces are a list of functions that have been called to get to where you are. The last function is the one that caused the error, and it's followed by all of its parent functions up until you get to main(). You can use this information to determine which line(s) of code might have caused your issue.
For example:
This is an example stack trace:
com/foo/bar/baz::main() [0x0050] [0x0050] () at com/foo/bar/baz.cpp:4
com::memory_error() [0x0040] () at memory_error.cpp:10
Make sure you are running the current version of your code.
If this doesn't make sense, don't worry—it's a lot more complicated than it sounds at first. The reason is that you might be running an old or incorrect version of your code on a different platform or browser than intended. To avoid these types of mistakes, it is best to always check what version number you're currently running by checking out the relevant Github page and comparing it with yours
Write a test to prove your bug exists and then fix the test.
The first step to debugging is to write a test that proves your bug exists. Next, fix the test so that it passes. Then use the test to make sure your fix works! If you don't understand what your tests are actually testing, or if they're not testing anything at all , this process can be really difficult. However, if you take these steps carefully and methodically—and especially if you spend some time thinking about them before writing them—you'll end up with far fewer bugs in the long run than someone who ignores their tests altogether.
Add more console statements to see where in the code flow things went wrong.
It's important to remember that console statements are helpful for debugging only when you've already added them to your code. So, if you're using a library or framework that doesn't provide any console functionality, start by adding some yourself:
Use console.log() to add debugging information in different parts of your code
Add debug messages into functions that may fail or have unexpected results
If you copy/pasted some code from somewhere, make sure you understand what it actually does.
What you should do:
If you copied and pasted the code from somewhere, make sure that you understand what it does. If it's a script, make sure it's a good one. If it's a library or snippet from Stack Overflow, make sure that they are good ones.
Debugging skills can be learned like anything else!
Debugging skills can be learned, like any other skill. It's not a magical ability that some people are born with and others aren't; it's something you develop by reading, writing, and testing code. And the more you practice debugging the better you'll get at it!
In conclusion
We are sure that with these tips, you will be able to improve your debugging skills and become a much better programmer. If you have any other suggestions for how someone can learn how to be more efficient at debugging, please let us know in the comments section below.