Feature: Step definitions parameters injection as fixtures

Step arguments are injected into step context and could be used as normal fixtures with the names equal to the names of the arguments by default.

Step’s argument are accessible as a fixture in other step function just by mentioning it as an argument

If the name of the step argument clashes with existing fixture, it will be overridden by step’s argument value. Value for some fixture deeply inside of the fixture tree could be set/override in a ad-hoc way by just choosing the proper name for the step argument.

Scenario: Step parameters are injected as fixtures by default

• Given File “conftest.py” with content:

  from re import compile as parse
  from pytest_bdd import given, then
  
  @given("I have a pickle", param_defaults=dict(freshness='salted'))
  @given(
    parse(r"I have a ((?P<freshness>\w+)\s)?cucumber"),
    param_defaults=dict(freshness='fresh')
  )
  def i_have_cucumber(freshness):
      ...
  
  @then("Taste of cucumber is salt")
  def i_check_salted_cucumber(freshness):
      assert freshness=='salted'
  

• Given File “Freshness.feature” with content:

  Feature:
    Scenario:
      Given I have a salted cucumber
      Then Taste of cucumber is salt
  

• Given File “test_freshness.py” with content:

  from enum import Enum
  from pytest import fixture
  from pytest_bdd import scenario
  class Freshness(Enum):
    FRESH = 'fresh'
    ROTTEN = 'rotten'
    SALTED = 'salted'
  
  @fixture
  def oracle_freshness():
    return Freshness.SALTED
  
  @scenario("Freshness.feature")
  def test_passing_feature(request, oracle_freshness):
    assert Freshness(request.getfixturevalue('freshness'))==oracle_freshness
  
  @scenario("Freshness.feature")
  def test_another_passing_feature(freshness, oracle_freshness):
    assert Freshness(freshness)==oracle_freshness
  

• When run pytest

  cli_args	–disable-feature-autoload

• Then pytest outcome must contain tests with statuses:

  passed
  2

Scenario: Step parameters injection as fixtures could be disabled

• Given File “conftest.py” with content:

  from re import compile as parse
  from pytest_bdd import given, then
  
  @given(
    "I have a pickle",
    param_defaults=dict(freshness='salted'),
    params_fixtures_mapping={...:None},
    target_fixtures=['cuke_taste']
  )
  @given(
    parse(r"I have a ((?P<freshness>\w+)\s)?cucumber"),
    param_defaults=dict(freshness='fresh'),
    params_fixtures_mapping=False,
    target_fixture='cuke_taste'
  )
  def i_have_cucumber(freshness):
      assert freshness is not None
      yield freshness
  
  @then("Taste of cucumber is salt")
  def i_check_salted_cucumber(cuke_taste):
      assert cuke_taste=='salted'
  

• Given File “Freshness.feature” with content:

  Feature:
    Scenario:
      Given I have a pickle
      Then Taste of cucumber is salt
  

• Given File “test_freshness.py” with content:

  import pytest
  from pytest_bdd import scenario
  from pytest_bdd.compatibility.pytest import FixtureLookupError
  @scenario("Freshness.feature")
  def test_passing_feature(request, cuke_taste):
    assert cuke_taste == 'salted'
    with pytest.raises(FixtureLookupError):
      request.getfixturevalue('freshness')
  

• When run pytest

  cli_args	–disable-feature-autoload

• Then pytest outcome must contain tests with statuses:

  passed
  1

Scenario: Step parameters renaming on injection as fixtures

• Given File “conftest.py” with content:

  from re import compile as parse
  from pytest_bdd import given, then
  
  @given(
    "I have a pickle",
    param_defaults=dict(freshness='salted'),
    params_fixtures_mapping={"freshness":"cuke_taste"}
  )
  @given(
    parse(r"I have a ((?P<freshness>\w+)\s)?cucumber"),
    param_defaults=dict(freshness='fresh'),
    params_fixtures_mapping={"freshness":"cuke_taste"}
  )
  def i_have_cucumber(cuke_taste, freshness):
      assert cuke_taste is not None
      assert freshness == cuke_taste
      yield cuke_taste
  
  @then("Taste of cucumber is salt")
  def i_check_salted_cucumber(cuke_taste):
      assert cuke_taste=='salted'
  

• Given File “Freshness.feature” with content:

  Feature:
    Scenario:
      Given I have a pickle
      Then Taste of cucumber is salt
  

• Given File “test_freshness.py” with content:

  import pytest
  from pytest_bdd import scenario
  from pytest_bdd.compatibility.pytest import FixtureLookupError
  
  @scenario("Freshness.feature")
  def test_passing_feature(request, cuke_taste):
    assert cuke_taste == 'salted'
    with pytest.raises(FixtureLookupError):
      request.getfixturevalue('freshness')
  

• When run pytest

  cli_args	–disable-feature-autoload

• Then pytest outcome must contain tests with statuses:

  passed
  1

Scenario: Only allowed step parameters injection as fixtures

• Given File “conftest.py” with content:

  from pytest_bdd import given
  
  @given(
    "I have an old pickle",
    param_defaults=dict(freshness='salted', age='old'),
    params_fixtures_mapping={"freshness"}
  )
  def i_have_cucumber(age, freshness):
      assert age == 'old'
      assert freshness == 'salted'
  

• Given File “Freshness.feature” with content:

  Feature:
    Scenario:
      Given I have an old pickle
  

• Given File “test_freshness.py” with content:

  import pytest
  from pytest_bdd import scenario
  from pytest_bdd.compatibility.pytest import FixtureLookupError
  
  @scenario("Freshness.feature")
  def test_passing_feature(request, freshness):
    assert freshness == 'salted'
    with pytest.raises(FixtureLookupError):
      request.getfixturevalue('age')
  

• When run pytest

  cli_args	–disable-feature-autoload

• Then pytest outcome must contain tests with statuses:

  passed
  1