Testing forms in Django - Mini Project: Build & Apply

Testing forms

📖 Scenario: You are building a simple Django web app with a form for users to submit their name and email. You want to write tests to check that the form works correctly.

🎯 Goal: Write Django form tests step-by-step to verify the form validates input and saves data properly.

📋 What You'll Learn

Create a Django form class with fields name and email

Add a test case class to test the form

Write a test to check the form is valid with correct data

Write a test to check the form is invalid with missing data

💡 Why This Matters

🌍 Real World

Forms are common in web apps for user input. Testing forms ensures users cannot submit wrong or incomplete data.

💼 Career

Django developers often write form tests to maintain app quality and prevent bugs in user input handling.

1

Create the form class

Create a Django form class called ContactForm with two fields: name as a CharField and email as an EmailField.

Django

# Your code here to create ContactForm with name and email fields

Need a hint?

Use forms.Form as the base class. Define name and email as form fields.

2

Set up the test case class

Create a Django test case class called ContactFormTest that inherits from django.test.TestCase.

Django

from django import forms
from django.test import TestCase

class ContactForm(forms.Form):
    name = forms.CharField()
    email = forms.EmailField()

# Your code here to create ContactFormTest inheriting from TestCase

Need a hint?

Import TestCase from django.test. Define an empty test class for now.

3

Write a test for valid form data

Inside ContactFormTest, write a test method called test_form_valid_data that creates a ContactForm with valid name and email data and asserts the form is valid using form.is_valid().

Django

from django import forms
from django.test import TestCase

class ContactForm(forms.Form):
    name = forms.CharField()
    email = forms.EmailField()

class ContactFormTest(TestCase):
    # Your code here to write test_form_valid_data method

Need a hint?

Create the form with a dictionary of valid data. Use self.assertTrue to check validity.

4

Write a test for invalid form data

Inside ContactFormTest, write a test method called test_form_invalid_data that creates a ContactForm with missing email and asserts the form is invalid using form.is_valid().

Django

from django import forms
from django.test import TestCase

class ContactForm(forms.Form):
    name = forms.CharField()
    email = forms.EmailField()

class ContactFormTest(TestCase):
    def test_form_valid_data(self):
        form = ContactForm(data={'name': 'Alice', 'email': '[e-mail]'})
        self.assertTrue(form.is_valid())

    # Your code here to write test_form_invalid_data method

Need a hint?

Create the form with missing email. Use self.assertFalse to check it is invalid.