KnowCardPython · Debugging & Testing
Why does test isolation matter, and what's a concrete bug from tests that aren't isolated?
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More in Debugging & Testing
What's the core difference in how doctest vs unittest define their test cases, and one practical trade-off?
You ship an API and use this to reject bad input:
```
def withdraw(amount):
assert amount > 0, "must be positive"
...
```
Why is this a real security bug in production?
Running a script with python -O myapp.py, what happens to every assert statement in the code, and what does __debug__ equal?
What is the difference between
```
assert x == y
```
and
```
self.assertEqual(x, y)
```
in a failing unittest?
A unittest class has this method. After running it with `python -m unittest`, the report says "Ran 0 tests". Why?
```
class MyTest(unittest.TestCase):
def checkCalc(self):
self.assertEqual(fac(5), 120)
```
In unittest, when do setUp and tearDown run relative to your test methods?
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