Tutorial 1: First Steps

Goal:Show basics, make first steps

Write the Feature Test

The following feature file provides a simple feature with one scenario in the known Given ... When ... Then ... language style (BDD).

# file:features/tutorial01_basics.feature
Feature: Showing off behave (tutorial01)

Scenario: Run a simple test
    Given we have behave installed
    When we implement a test
    Then behave will test it for us!

Provide the Test Automation

To be able to execute the feature file, you need to provide a thin automation layer that represents the steps in the feature file with Python functions. These step functions provide the test automation layer (fixture code) that interacts with the system-under-test (SUT).

# file:features/steps/step_tutorial01.py
# ----------------------------------------------------------------------------
# STEPS:
# ----------------------------------------------------------------------------
from behave import given, when, then

@given('we have behave installed')
def step_impl(context):
    pass

@when('we implement a test')
def step_impl(context):
    assert True is not False

@then('behave will test it for us!')
def step_impl(context):
    assert context.failed is False

Run the Feature Test

When you run the feature file from above (with coloring enabled):

$ behave ../features/tutorial01_basics.feature
Feature: Showing off behave (tutorial01)   # ../features/tutorial01_basics.feature:1

  Scenario: Run a simple test        # ../features/tutorial01_basics.feature:3
    Given we have behave installed   # ../features/steps/step_tutorial01.py:12
    When we implement a test         # ../features/steps/step_tutorial01.py:16
    Then behave will test it for us! # ../features/steps/step_tutorial01.py:20

1 feature passed, 0 failed, 0 skipped
1 scenario passed, 0 failed, 0 skipped
3 steps passed, 0 failed, 0 skipped, 0 undefined
Took 0m0.000s

As alternative you can run the feature with plain formatting (or another formatter):

$ behave --format=plain --show-timings ../features/tutorial01_basics.feature
Feature: Showing off behave (tutorial01)

  Scenario: Run a simple test
    Given we have behave installed ... passed in 0.000s
    When we implement a test ... passed in 0.000s
    Then behave will test it for us! ... passed in 0.000s

1 feature passed, 0 failed, 0 skipped
1 scenario passed, 0 failed, 0 skipped
3 steps passed, 0 failed, 0 skipped, 0 undefined
Took 0m0.000s