Tests that give you confidence
A test checks an expected behavior. assert fails if a condition is false. Test ordinary inputs, edge cases and errors. A few passing tests increase confidence but do not prove every possible input is correct.
हिन्दी में समझें
टेस्ट अपेक्षित व्यवहार जाँचता है। assert गलत शर्त पर विफल होता है। सामान्य, किनारे के और गलत इनपुट जाँचें। कुछ टेस्ट पास होने से हर इनपुट सही सिद्ध नहीं होता।
अभ्यास: add(0, 0) के लिए assert जोड़ें और 3 tests passed प्रिंट करें।
Hinglish mein samjhein
Test expected behavior check karta hai. assert false hone par fail hota hai. Normal, edge cases aur errors test karo. Kuch tests pass hone se sab inputs guaranteed sahi nahi hote.
Practice: add(0,0) ka assert jodo aur 3 tests passed print karo.
A small Python example
def add(a, b):
return a + b
assert add(2, 3) == 5
assert add(-1, 1) == 0
print("2 tests passed")The browser playground runs real Python with Pyodide. Use sample variables instead of interactive input(). Browser package support differs from desktop Python.
Try this example in the Python playground →Practise this idea
Add an assertion for add(0, 0) and print 3 tests passed.
Check answer & explanation
def add(a, b):
return a + b
assert add(2, 3) == 5
assert add(-1, 1) == 0
assert add(0,0)==0
print("3 tests passed")The added zero-input assertion covers another behavior. Three test cases pass before the success message prints.
Stuck in the course? Choose Check answer for either the challenge or quiz. Read the explanation and continue to the next lesson at your own pace.
Check your understanding
When does assert fail?
Check the quiz answer
When its condition is false
A false assertion raises AssertionError.
References & corrections
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