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Syntax - Tasty Web Development Treats

How to Get Better at Debugging

Scott and Wes detail the tips and tools you need to get better at debugging.

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Show Notes

4:00

  • Read the stack trace

7:35

  • Make sure you aren’t debugging production
  • Make sure you’re not cached

8:40

  • Check the network panel for the whole response
  • CORS (Cross-Origin Resource Sharing)

12:04

  • Use debugger commands in the browser
  • Set breakpoints (race conditions

13:40

  • Use Source Maps

15:29

  • Make full use of all console methods
    • console.group/groupEnd/info/
    • console.log({objNAme})

17:02

  • View your code in other browers
  • Make sure your browser is up to date

18:50

  • Step into and step over function
  • Useful for especially tricky issues

19:47

  • Look into Scope in dev tools panel

20:33

  • Recreate it in CodePen or Create React App
    • Helps to quarantine your code
    • Verify where the problem actually is

24:12

  • Take a break
    • Helps clear your head and approach your problem from a different angle

25:40

  • Rubber Duck Debugging
    • Forcing yourself to talk it out will often reveal problems/issues

26:40

  • Check Github issues / ask in Slack
    • Leave your solution in the comments for others

28:12

  • Use Node --inspect flag

29:57

  • Read the code in your libs (if you can)

32:34 - Chrome Dev Tools Tabs Rundown

  • 33:10 - Network tab
  • 34:15 - Preformance tab
  • 35:58 - Lesser known tools
    • 36:15 - Firefox Grid Debug
    • 36:20 - Firefox Fonts tab
    • 37:10 - More tools (three dots menu in top right of Chrome Dev Tools window)
    • 37:39 - Chrome Animations Inspector
    • 38:34 - /dev tips & Modern DevTools Course
    • 39:41 - Chrome & FF Layers for 3d and full view of canvas & window
    • 40:51 - Sensors for overriding fake devices sensors
      • Hot tip: Use Instagram on the desktop - Go to Instagram and set the user agent to iPad and it will work as it does on that actual device
      • Hot tip: Get free internet on a plane - If the airplane offers free internet for a certain device, change your user agent to that device and then switch back
    • 43:12 - Favorite DevTools extensions
  • 44:06 - Application/Storage tab
  • 44:41 - FireFox Grid Inspector
××× SIIIIICK ××× PIIIICKS ×××
  • Scott: Hotel Tonight App
  • Wes: Coffee table - If you’re trying to build an outdoor coffee table, use a peice of granite
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