I am currently trying to learn how to Unit Test with Python and was introduced to the concept of Mocking, I am a beginner Python developer hoping to learn the concepts of TDD alongside my development of Python skills. I am struggling to learn the concept of mocking a class with a given input from the user for Python unittest.mock documentation. If I could get an example of how I would mock a certain function, I would be really grateful. I will use the example found here: Example Question
class AgeCalculator(self): def calculate_age(self): age = input("What is your age?") age = int(age) print("Your age is:", age) return age def calculate_year(self, age) current_year = time.strftime("%Y") current_year = int(current_year) calculated_date = (current_year - age) + 100 print("You will be 100 in", calculated_date) return calculated_date
Please could somebody create my an example Unit Test using Mocking to automate the input for age so that it would return the year which the mock’ed age would be 100.
You do not mock inputs, but functions. Here, mocking
input is basically the easiest thing to do.
from unittest.mock import patch @patch('yourmodule.input') def test(mock_input): mock_input.return_value = 100 # Your test goes here
You can mock the buildins.input method in Python3.x, and using with statements to control the scope of mocking period.
import unittest.mock def test_input_mocking(): with unittest.mock.patch('builtins.input', return_value=100): ...
Here – I fixed
calculate_age(), You try `calculate_year.
class AgeCalculator: #No arg needed to write this simple class def calculate_age(): # Check your sample code, no 'self' arg needed #age = input("What is your age?") #Can't use for testing print ('What is your age?') #Can use for testing age = '9' # Here is where I put in a test age, substitutes for User Imput age = int(age) print("Your age is:", age) #return age -- Also this is not needed for this simple function def calculate_year(age): # Again, no 'Self' arg needed - I cleaned up your top function, you try to fix this one using my example current_year = time.strftime("%Y") current_year = int(current_year) calculated_date = (current_year - age) + 100 print("You will be 100 in", calculated_date) return calculated_date AgeCalculator.calculate_age()
From what I see in your code, you should look up how to build functions – And please don’t take that in an offensive manner. Also you could just test your function by hand by running it. As your code stands, it does not run.