7. Testing, Debugging, Exceptions, and Assertions 

*My takeaways:* 1. Defensive programming: testing/validation and debugging 4:20 2. Three classes of test: unit testing, regression testing and integration testing 6:25 3. Testing approaches: natural boundaries for numbers, random testing, black box testing and glass box testing 7:45 4. Black box testing is based on specification, an example 9:05 5. Glass box testing tries to test every single path of the code 10:20 6. Using the print statement to debug 15:17 7. General debugging steps 17:20 8. How to debug logic errors 18:42, try rubber ducky debugging 9. Do and Don't 20:00 10. Exceptions 21:40 11. Assertions 37:45

She's really easy to learn from. Thank you for teaching and positing this online without charge

"Decide it's high protein and declare it a feature". That's hilarious. ahahah

Amazing how she gets better as the lectures go on

although i am not a native or the best in english , i can hear every word and understand her i want to thank you a lot Dr. Ana

Dr. Anna Bell is a great instructor, Thank you MIT OCW for making this high quality content online absolutely for free.

Dr.Hanna, you are awesome instructor and you made learning fun. Thank you very much!!!!

Love this session, fund very easy and clear and fun. Thank you so much for sharing..

pre labeling ​​0:01:02 We aim for high quality - an analogy with soup 0:02:00​ 0:03:46 Programming so far 0:06:48 Classes of test 0:08:02 Testing approaches 0:10:00 Glass box testing ​0:11:02 ​0:11:48 ​0:14:00​ 0:16:00 0:17:26 Debugging steps 0:19:33 0:20:05 Don't and Do ​0:22:16 Other types of exception 0:24:08 ​ 0:25:41 Handling specific exception 0:27:09​ Other exception 0:28:15 What to do with exception 0:31:15 ​Example : Raising an exception 0:32:00 0:33:52 ​ 0:35:31 ​Option 1 0:37:01​ Option 2 0:38:38 Example 0:40:48 Where to use assertion

Dr. Ana Bell is a great instructor!

this lecture was a godsend, feeling a lot more eager and motivated to learn programming, especially when there are tools at your disposal when shit hits the fan !!

Where was this video when I started learning programming, would've saved me a lot of time

Watched so many videos but only Dr Ana Bell's one stuck! Thank you!

thank you ,mit

Your voice and words are very clear good for concentration

26:35 for the last case, it will raise an Exception on interrupts like KeyboardInterrupt when you press CTRL+C. Programmers should be careful having broad except cases. If you had an infinite loop that caught all exceptions it would be hard to kill the program.

perhaps the most valuable lecture in this series

Dr. Anna Bell. This is great.

love these lectures

Bravissima, complimenti!!!

At 26:42 she says that she couldn't think of an error that would be raised besides these two. I thought of one: if a/b is too large, Python won't be able to represent it as a float and would raise an OverflowError

You are the best👏🏻👏🏻❤️ thanks Professor Anna

We use the "rubber ducking" method, not for coding but for general problem solving in our IT department with an empty pringles can.

this proffesor is really great i wish i could study for her

"Decide it's high protein and declare it a feature"... I may have worked as a software engineer for that student's father in the past.

Anyone: Did you learn anything today? Me: Yeah, talking to rubber duckies helps me with my problems.

26:43 one more exception can be KeyboardInterrupt

thanks a lot

These are great, and Ana is great. Was worried when there was a new teacher in the last video.

Does anyone know in which video she talks about the Rubber Ducky?

Lecturer is very good, it's not easy teaching programming. But for some reason I'm hung up on her pacing back and forth, and I can't get it out of my head! I wish I never thought of it now.

I am surprised that no one in the class asked why does it raise ValueError instead of TypeError, as the user provides the wrong Type of input i.e string Type whereas the expected input was integer Type. I had to google to find the answer. May be they already know the answer ?

36:21 How did you divide 100 by 3 and got 15.41666? Same for other lines. You should debug your code

Could debugging be fun; I hope so!

thanks she is back after him

CD Projekt Red should watch this.

How do I do the thing where she selects multiple lines of code and adds a # in front of each of them at once?

Your brain is the kitchen. Keep that place clean and sharp

be conservative in what you output and liberal in accepting your input? ... exceptions demand catches, just as return values rquire if's

i still havent found out how to get all the #(comments) away like shes does. she highlights a block and does something that gets them to all be not commented then

Current American model for dealing with the first analogy: Burn the ceiling down

The first answer was genius, she laughs, but thats what companies do all the time release buggy software .....then endless patches.

I feel like 85% of the engineers I work with skipped this class.

👍👍👍

COVERED soup only prevents *more* bugs from invading. Complete cleaning of the house means deleting all applications, removing the entire operating system, & then low-level formatting everything! *yeah* baby *yeah*

is there a way to know which pset to do after which lecture?

what is need of raising the exception? we can simply use print statement and break ?

she has BLE: big lecture energy

stand still damn it!

Don't backup your code, make a commit with git

32:53

18:24

comment the code what you have written and not working, so you don't endup doing the same implemenation again while doing the testing, cleanup at the end of finding the solution.

19:33 Professor's kid is probably going start to dreaming in code and grow up to be a wizard.

Try not to use ingredients with bugs already in.

That program for the class wouldn't work. The first student in class_list would get a correct entry in new_stats but then in the next step of the for-loop his grades and the next student would go into new_stats. Also, the program would try to do avg on his name, so you would definitely get an error message.

Deadpool never comes to any tests😢

Voice crack at 38:57

The abundant look prenatally slow because test noteworthily tug barring a many confirmation. mammoth, hollow passive

disappoint beyond belief!!!

I wish she had praticed a little before lectures. Maybe 1/5 of lectures goes with "ehm", "umm", "err" or an awkward silence.