tests

pytest_bdd/exceptions.py

@@ -0,0 +1,6 @@
+"""Exception classes."""
+
+
+class FeatureError(Exception):
+    """Feature parse error."""
+    pass

pytest_bdd/feature.py

@@ -21,6 +21,7 @@ one line.
 """
 
 from pytest_bdd.types import SCENARIO, GIVEN, WHEN, THEN
+from pytest_bdd.exceptions import FeatureError
 
 # Global features dictionary
 features = {}
@@ -85,6 +86,7 @@ class Feature(object):
 
         scenario = None
         mode = None
+        prev_mode = None
 
         with open(filename, 'r') as f:
             content = f.read()
@@ -94,6 +96,18 @@ class Feature(object):
                     continue
 
                 mode = get_step_type(line) or mode
+
+                if mode == GIVEN and prev_mode not in (GIVEN, SCENARIO):
+                    raise FeatureError('Given steps must be the first in withing the Scenario')
+
+                if mode == WHEN and prev_mode not in (GIVEN, WHEN):
+                    raise FeatureError('When steps must follow Given steps')
+
+                if mode == THEN and prev_mode not in (WHEN, THEN):
+                    raise FeatureError('Then steps must follow When steps')
+
+                prev_mode = mode
+
                 # Remove Given, When, Then, And
                 line = remove_prefix(line)
 

pytest_bdd/steps.py

@@ -22,6 +22,7 @@ def no_error_message(browser):
 import pytest
 
 from pytest_bdd.types import GIVEN, WHEN, THEN
+from pytest_bdd.feature import remove_prefix
 
 
 def given(name):
@@ -50,7 +51,7 @@ def _decorate_step(step_type, step_name):
     """
     def decorator(func):
         func.__step_type__ = step_type
-        func.__step_name__ = step_name
+        func.__step_name__ = remove_prefix(step_name)
         if step_type == GIVEN:
             return pytest.fixture(func)
         return func

tests/feature/steps.feature

@@ -0,0 +1,8 @@
+Scenario: Executed step by step
+    Given I have a foo fixture with value "foo"
+    And there is a list
+    When I append 1 to the list
+    And I append 2 to the list
+    And I append 3 to the list
+    Then foo should have value "foo"
+    And the list should be [1, 2, 3]

tests/feature/test_steps.py

@@ -0,0 +1,39 @@
+from pytest_bdd import scenario, given, when, then
+
+
+test_steps = scenario('steps.feature', 'Executed step by step')
+
+
+@given('I have a foo fixture with value "foo"')
+def foo():
+    return 'foo'
+
+
+@given('there is a list')
+def results():
+    return []
+
+
+@when('I append 1 to the list')
+def append_1(results):
+    results.append(1)
+
+
+@when('I append 2 to the list')
+def append_2(results):
+    results.append(2)
+
+
+@when('I append 3 to the list')
+def append_3(results):
+    results.append(3)
+
+
+@then('foo should have value "foo"')
+def foo_is_foo(foo):
+    assert foo == 'foo'
+
+
+@then('the list should be [1, 2, 3]')
+def check_results(results):
+    assert results == [1, 2, 3]

tests/feature/test_wrong.py

@@ -0,0 +1,25 @@
+"""Test wrong feature syntax."""
+
+import pytest
+
+from pytest_bdd import scenario
+from pytest_bdd.exceptions import FeatureError
+
+
+@pytest.fixture(params=[
+    'When after then',
+    'Then first',
+    'When first',
+    'Given after When',
+    'Given after Then',
+])
+def scenario_name(request):
+    return request.param
+
+
+def test_wrong(request, scenario_name):
+    """Test wrong feature scenarios."""
+
+    sc = scenario('wrong.feature', scenario_name)
+    with pytest.raises(FeatureError):
+        sc(request)

tests/feature/wrong.feature

@@ -0,0 +1,27 @@
+Scenario: When after then
+	Given I don't always write when after then, but
+	When I do
+	Then its fine
+	When I do it again
+	Then its wrong
+
+
+Scenario: Then first
+	Then it won't work
+
+
+Scenario: When first
+	When it won't work
+
+
+Scenario: Given after When
+	Given something
+	When something else
+	Given won't work
+
+
+Scenario: Given after Then
+	Given something
+	When something else
+	Then nevermind
+	Given won't work