Python Automation Framework-Behave Framework:

Behave is a Python testing framework specifically designed for behavior-driven development (BDD). BDD is a software development methodology that focuses on collaboration between developers, QA, and non-technical stakeholders by expressing requirements and specifications in a human-readable language.

Behave uses the Gherkin language, which is a simple, structured language for describing software behaviors. Gherkin is primarily used for writing executable specifications in a format that is easy for both technical and non-technical individuals to understand.

Prerequisites for Behave:

Behave can be used by anyone who possesses basic knowledge of Python. Before installing Behave, do the following:

• Install any version of Python over 2.7.14
• Install a Python package manager or pip
• Install Pycharm or a similar IDE.

Key Benefits of Behave:

• In Behave, system behavior is defined by semi-formal language and involves the use of a domain vocabulary that ensures behavior remains constant in the organization.
• There are building blocks available for the execution of a large variety of test cases.
• Facilitates effective coordination of development teams’ work on diverse modules with some similar features.
• All specs are in a similar format, offering managers better clarity on the output of developers and QAs.

Disadvantages of Behave:

• Works optimally only for black-box testing.
• Not the best fit for a unit or integration testing, as the verbosity inherent in these tests, can lead to complications in test scenarios.

When should you choose behave?

If you need to perform black-box testing, behave is a great option. While other Python testing frameworks like the Robot Framework and Pytest Framework can also be used for this type of testing, behave is particularly suitable when testing for web applications because its BDD methodology offers readable test scenarios for non-developers.

Here’s a brief overview of how Behave works:

1. Feature Files:

Behave tests are defined in feature files using Gherkin syntax. These files typically have a .feature extension. Feature files contain scenarios that describe the expected behavior of the software.

Feature: Calculator
  In order to avoid mistakes
  As a clumsy user
  I want to be able to add two numbers

  Scenario: Add two numbers
    Given the first number is 2
    And the second number is 3
    When the numbers are added
    Then the result should be 5

2. Step Definitions:

Steps in the feature files are associated with Python code through step definitions. These are implemented in Python files and define the actual behavior of each step.

from behave import given, when, then

@given('the first number is {number}')
def step_given(context, number):
    context.first_number = int(number)

@given('the second number is {number}')
def step_given(context, number):
    context.second_number = int(number)

@when('the numbers are added')
def step_when(context):
    context.result = context.first_number + context.second_number

@then('the result should be {result}')
def step_then(context, result):
    assert context.result == int(result)

3. Running Tests:

Behave provides a command-line interface to run tests. You can execute the tests by running the behave command in the terminal. Behave will discover and execute the scenarios defined in the feature files.

behave

Behave encourages collaboration and communication by allowing stakeholders to contribute to the creation of feature files. It also promotes a clear separation between the specification of behavior and its implementation, making it a useful tool for teams practicing BDD.