Introduction
============
Library to convert BDD_ features into Python unittest.TestCase classes. Run the
tests with your favorite test runner, like pytest, unittest or nose.
See the demo folder for an example.
Example
=======
Let's take a calculator as an example.
Create a plain text file called calculator.feature containing the BDD_-style
feature description:
.. code::
Feature: Basic math operations
Test addition
Scenario: add
Given the value 10
When adding 7
Then the result is 17
Scenario: add a negative value
Given the value 19
When adding -11
Then the result is 8
This is the text you can discuss with the customer and agree on.
Next write a backing file called test_calculator.py containing the code to
run this feature:
.. code::
import os
from bdd import Environment
from calculator import Calculator
env = Environment()
env.context.calculator = Calculator()
@env.given('the value {:d}')
def step(context, value):
context.calculator.value = value
@env.when('adding {:d}')
def step(context, value):
context.calculator.add(value)
@env.then('the result is {:d}')
def step(context, value):
assert context.calculator.value == value
def rel(p):
this_dir = os.path.dirname(os.path.abspath(__file__))
return os.path.join(this_dir, p)
CalculatorTestCase = env.load_feature_as_testcase('calculator.feature')
Finally, write the actual production code to implement the calculator, in
a file called calculator.py:
.. code::
class Calculator:
def __init__(self):
self.value = 0
def add(self, value):
self.value += value
Now run the tests with, for example, pytest:
.. code::
$ python -m pytest test_calculator.py -v
=========== test session starts ===========================
platform linux -- Python 3.5.1, pytest-2.9.1
collected 2 items
test_calculator.py::CalculatorTestCase::test_scenario_0 <- bdd.py PASSED
test_calculator.py::CalculatorTestCase::test_scenario_1 <- bdd.py PASSED
.. _BDD: https://en.wikipedia.org/wiki/Behavior-driven_development
References
==========
A really good python bdd library is behave_.
.. _behave: http://pythonhosted.org/behave/
Changelog
=========
**0.2**
- Add tag support
**0.1 (Jun 2, 2016)**
- Initial release
.. image:: https://travis-ci.org/windelbouwman/bdd.svg?branch=master
:target: https://travis-ci.org/windelbouwman/bdd
.. image:: https://codecov.io/gh/windelbouwman/bdd/branch/master/graph/badge.svg
:target: https://codecov.io/gh/windelbouwman/bdd
