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Ruchi Pakhle
Ruchi Pakhle

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How to write unit-tests as a beginner in python

As a beginner in Python, writing unit tests can seem a bit overwhelming, but it's an essential skill to learn inorder to become a proficient programmer. Unit tests are used to ensure that our code is functioning as expected and can help identify and prevent bugs early in the development process.

Here are some steps that I followed while writing unit tests in Python:

Understanding the basic concept of unit tests:
Unit tests are written to test individual components or functions of a program, independent of the rest of the system. The goal is to ensure that each unit of code works as expected, and the code as a whole works correctly.

Choosing a testing framework:
Python has several testing frameworks to choose from, such as Pytest, Unittest, and Nose. Pick one that you feel comfortable with, and start exploring.

Create a separate test file:
Create a new file and name it with "test"_ prefix like, for example, "" This file should contain all the test functions for the code that w want to test. Make sure that you are not mixing your production code with your test code.

Write your first test function:
A test function should be named with a prefix of "test_" followed by the function name that you want to test. The test function should then include an assert statement that checks if the function's output matches the expected output.

For example, let's say we want to test the following function:

def add(x, y):
return x + y

You can write a test function like this:

def test_add():
assert add(2, 3) == 5

Run your tests:
Use your testing framework to run your tests and check if they pass or fail. If the test passes, you will see a green output, and if it fails, you will see a red output. Fix the code until all tests pass.

Add more test functions:
Write more test functions to cover different scenarios and inputs. For example, you can test negative numbers, decimal numbers, or edge cases.

Refactor your code:
Refactor your code and run your tests again. Make sure that your tests still pass after refactoring.

In short, unit tests are essential for ensuring code quality, and learning how to write them is a valuable skill for any developer.

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