If you want to deliberately trigger a test failure, the default way is to raise a "Failure" exception.

This is considered an "expected exception".

This means that the story failed on will be highlighted but not the stack trace. This makes story failure message a bit cleaner.

Debugging information can be fed to the exception.

See also:

• Treat other exceptions as expected
• Compare two strings

Code Example

engine.py:

from hitchstory import BaseEngine, no_stacktrace_for, Failure
from code_that_does_things import raise_example_exception, output, ExampleException

class Engine(BaseEngine):
    def passing_step(self):
        pass

    def failing_step(self):
        raise_example_exception("Towel not located")

    @no_stacktrace_for(ExampleException)
    def failing_step_without_stacktrace(self):
        raise_example_exception("Expected exception")

    def raise_special_failure_exception(self):
        raise Failure("Special failure exception - no stacktrace printed!")

    def step_that_will_not_run(self):
        pass

    def on_failure(self, result):
        pass

    def not_executed_step(self):
        pass

example.story:

Failing story:
  steps:
    - Raise special failure exception
    - Step that will not run
    - Step that will not run

With code:

from hitchstory import StoryCollection
from engine import Engine
from pathlib import Path

story_collection = StoryCollection(Path(".").glob("*.story"), Engine())

story_collection.one().play()

Will output:

RUNNING Failing story in /path/to/working/example.story ... FAILED in 0.1 seconds.

    Failing story:
      steps:
      - Raise special failure exception
      - Step that will not run
      - Step that will not run

hitchstory.exceptions.Failure

    Test failed.

Special failure exception - no stacktrace printed!

Executable specification

Documentation automatically generated from special-failure-exception.story storytests.