Steps files¶

The steps files are responsible for implementing the tests that will be executed by the framework. They are written in Gherkin, a language that allows you to write tests in a human-readable format. The framework will execute these tests by interacting with the game.

Example of a steps file:

@given("first pipe at {i:f} and second pipe at {j:f}")
def step_impl(context, i, j):
    context.engine_driver.set_scene("res://Tests/PipeSizeTest/PipeSizeTest.tscn")
    context.instance_driver.set_pipes_position(i, j)


@when("bird flies")
def step_impl(context):
    return Fly()


@then("bird should have passed {i:d} pipes")
def step_impl(context, i):
    context.assert_true(context.score >= i)

Each step file while require to implement the following methods using python decorators:

@given(step_description)

Parameters:: step_description (str) – The description of the given step.
Type:: Method
Description:: This method will be executed before each test. It is responsible for setting up the game state before the test starts.

@when(step_description)

Parameters:: step_description (str) – The description of the when step.
Type:: Method
Description:: The method will be executed before every test. It return a Behavior object that will make the actions in the game.

@then(step_description)

Parameters:: step_description (str) – The description of the then step.
Type:: Method
Description:: This method will be executed after the game loop. It is responsible for asserting the expected game state after the test is finished.

Note

The given, when and then decorators can handle arguments.

Get the game state¶

The game state is represented by the test_context object. This object is include as the first argument of the methods decorated by given, when and then. For instance, if you want to get the player health, you can do it like this:

player_health = test_context.player.health

Set-Up the test with the engine_driver (in @given)¶

Engines could need to be setup before starting the test. This is the role of the engine_driver. For instance, in Godot. You need to chose the scene that will be instanced.

test_context.engine_driver.set_scene("res://tests/integration/pipe_height.tscn")

Call game methods with the instance_driver (in @given)¶

You can call game methods in the @given method. For instance, if you want to set the player health to 100, you can do it like this:

test_context.instance_driver.set_player_health(100)

Note

In Godot those methods need to be exposed in the script of the FeatureNode root.

Assertions¶

The @then decorator is used to define the conditions under which a test is successful. As you can see on the schema, it will be executed every time a game is terminated. You have a list of assertion functions that you can use to define your conditions.

@then("The player killed the monster")
def test_impl(test_context):
    test_context.assert_true(test_context.monster.is_dead)

Assertion functions¶

assert_true(condition)¶

Parameters:: condition – The condition to assert.
Description:: Asserts that condition is True.

assert_false(condition)¶

Parameters:: condition – The condition to assert.
Description:: Asserts that condition is False.

assert_equal(actual, expected)¶

Parameters:

actual – The actual value.
expected – The expected value.

Description:

Asserts that actual is equal to expected.

assert_not_equal(actual, expected)¶

Parameters:

actual – The actual value.
expected – The expected value.

Description:

Asserts that actual is not equal to expected.

assert_greater(actual, expected)¶

Parameters:

actual – The actual value.
expected – The expected value.

Description:

Asserts that actual is greater than expected.

assert_greater_equal(actual, expected)¶

Parameters:

actual – The actual value.
expected – The expected value.

Description:

Asserts that actual is greater than or equal to expected.

assert_less(actual, expected)¶

Parameters:

actual – The actual value.
expected – The expected value.

Description:

Asserts that actual is less than expected.

assert_less_equal(actual, expected)¶

Parameters:

actual – The actual value.
expected – The expected value.

Description:

Asserts that actual is less than or equal to expected.

assert_between(actual, min, max)¶

Parameters:

actual – The actual value.
min – The minimum value.
max – The maximum value.

Description:

Asserts that actual is between min and max.

assert_not_between(actual, min, max)¶

Parameters:

actual – The actual value.
min – The minimum value.
max – The maximum value.

Description:

Asserts that actual is not between min and max.

Example:

test_context.assert_false(test_context.monster.is_dead)
test_context.assert_not_between(test_context.player.health, 0, 100)