Story that rewrites itself

Hitch stories can be partially rewritten when the code is changed when a step involves verifying a block of text.

It is a time saver when you only want to make modifications to messages output by a program and ensure that those modifications are verified.

Instead of manually constructing the exact output you are expecting you can simply visually inspect the output to verify that it is the desired output.

This example shows a story being run in "rewrite" mode - where text strings are rewritten. This mode can be used when doing development when you expect textual changes.

If the story passes then the file will be rewritten with the updated contents. If the story fails for any reason then the file will not be touched.

If rewrite=False is fed through to the story engine instead, the story will always fail when seeing different text. This mode can be used when, for example, running all the stories on jenkins or when you are refactoring and not expecting textual output changes.

example.story:

Do things:
  steps:
    - Do thing: x
    - Do thing: y
    - Do thing: z
    - Do other thing:
        variable 1: a
        variable_2: b

  variations:
    Do more things:
      following steps:
        - Do thing: c

engine.py:

from hitchstory import BaseEngine

class Engine(BaseEngine):
    def __init__(self, rewrite=True):
        self._rewrite = rewrite

    def do_thing(self, variable):
        if self._rewrite:
            self.current_step.update(
                variable="xxx:\nyyy"
            )

    def do_other_thing(self, variable_1=None, variable_2=None):
        if self._rewrite:
            self.current_step.update(
                variable_2="complicated:\nmultiline\nstring"
            )

With code:

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

Rewritten

StoryCollection(Path(".").glob("*.story"), Engine(rewrite=True)).ordered_by_name().play()

Will output:

RUNNING Do things in /path/to/working/example.story ... SUCCESS in 0.1 seconds.
RUNNING Do things/Do more things in /path/to/working/example.story ... SUCCESS in 0.1 seconds.

File example.story should now contain:

Do things:
  steps:
  - Do thing: |-
      xxx:
      yyy
  - Do thing: |-
      xxx:
      yyy
  - Do thing: |-
      xxx:
      yyy
  - Do other thing:
      variable 1: a
      variable_2: |-
        complicated:
        multiline
        string


  variations:
    Do more things:
      following steps:
      - Do thing: |-
          xxx:
          yyy

No changes

StoryCollection(Path(".").glob("*.story"), Engine(rewrite=False)).ordered_by_name().play()

Will output:

RUNNING Do things in /path/to/working/example.story ... SUCCESS in 0.1 seconds.
RUNNING Do things/Do more things in /path/to/working/example.story ... SUCCESS in 0.1 seconds.

Then the example story will be unchanged.

Executable specification

Documentation automatically generated from rewrite-story.story storytests.