INSTRUCTIONS

###Setup

1. Make sure Python 2.7 is installed on your machine.

2. Install the Lettuce library and nose toolkit for Python. (These are Python-based tools for Behavior Driven development.)

   For Mac & Linux: You can simply install it using pip install tool.
   sudo pip install lettuce
sudo pip install nose

   For Windows: You can use easy_install (a Python module that can automatically download, build, install, and manage Python packages) to get lettuce and nose. For more information, refer to the following link: https://pypi.python.org/pypi/setuptools

   To check if you have the easy_install module, execute the following command easy_install --version. You should get something similar to the below output:

    setuptools 18.5 from c:\python27\lib\site-packages\setuptools-18.5-py2.7.egg (Python 2.7)
   

   Install easy_install (if you do not have this module):

   1. Download ez_setup.py from here: https://bootstrap.pypa.io/ez_setup.py
   2. Run ez_setup.py using python ez_setup.py
   3. Ensure that you have the following entries in your PATH variable: C:\Python27\Scripts;C:\Python27 (or pointing to your python folder)
      1. NOTE: You may need to re-open command prompt for changes to take effect.
   4. Verify executing easy_install --version gives some output like mentioned above

   Install lettuce and nose: easy_install lettuce
easy_install nose

   The above steps were adapted from the following tutorial for reference:

   http://www.erlisvidal.com/2010/10/how-install-lettuce-windows.html

3. Fork this repo and clone it on your local machine.

4. You can test any feature by navigating to the directory of the repo, and then using: lettuce tests/features/feature_name.feature

Example:

nitish@nitish-VirtualBox:~/Desktop/BDD-Example$ lettuce tests/features/calculator_add.feature 
/usr/local/lib/python2.7/dist-packages/fuzzywuzzy/fuzz.py:33: UserWarning: Using slow pure-python SequenceMatcher. Install python-Levenshtein to remove this warning
  warnings.warn('Using slow pure-python SequenceMatcher. Install python-Levenshtein to remove this warning')

Feature: Acceptance Test for the                 # tests/features/calculator_add.feature:1
  add() function of Calculator                   # tests/features/calculator_add.feature:2

  Background:
    Given I am using the calculator              # tests/features/steps.py:7
    Given I am using the calculator              # tests/features/steps.py:7

  Scenario: Calculate 2 plus 2 on our calculator # tests/features/calculator_add.feature:7
    Given I input "2" add "2"                    # tests/features/steps.py:13
    Then I should see "4"                        # tests/features/steps.py:33

1 feature (1 passed)
1 scenario (1 passed)
2 steps (2 passed)

###Assignment

You will be adding two functions to our calculator program: one that calculates the volume of a rectangular prism (length x width x height) given three input integers, and one that calculates the factorial of a single input integer.

1. In the tests/features directory, create .feature files for calculator_factorial and calculator_volume, using the format provided by the calculator_add.feature and calculator_subtract examples. For each feature file, create both a scenario and a scenario outline with at least three sets of inputs. -Don't worry about negative numbers when testing volume or factorial. -If you want to try taking the factorial a negative number, the expected output should be None.

2. Open the steps.py file and add the corresponding volume and factorial test functions. Hint: the phrasing must match your feature file exactly.

3. Run your tests using lettuce tests/features/calculator_volume.feature and lettuce tests/features/calculator_factorial.feature. The tests should fail.

4. In the app directory, open calculator.py and finish implementing the volume and factorial functions.

5. Run the two feature tests again. This time, they should pass.