├── .coveragerc ├── .gitignore ├── .pre-commit-config.yaml ├── .travis.yml ├── LICENSE ├── README.md ├── mimics ├── __init__.py ├── constants.py ├── deferred.py ├── inspect.py └── record.py ├── requirements-dev.txt ├── setup.cfg ├── setup.py └── tests ├── conftest.py ├── test_defer_class_definition.py ├── test_deferred.py └── test_use_cases.py /.coveragerc: -------------------------------------------------------------------------------- 1 | [run] 2 | branch = True 3 | source = mimics 4 | omit = 5 | */.env/*, 6 | *apps.py, 7 | *migrations/*, 8 | *settings*, 9 | *tests/*, 10 | *wsgi.py, 11 | */manage.py, 12 | launch.py, 13 | setup.py, 14 | */__init__.py, 15 | 16 | [report] 17 | ignore_errors = True 18 | -------------------------------------------------------------------------------- /.gitignore: -------------------------------------------------------------------------------- 1 | *.csv 2 | run.sh 3 | recreate_db.sh 4 | node_modules 5 | *.cache 6 | __pycache__ 7 | .coverage 8 | htmlcov 9 | *.pyc 10 | *.swp 11 | AUTHORS 12 | ChangeLog 13 | tables.csv 14 | .pytest_cache/ 15 | *.png 16 | # Pyenv 17 | .python-version 18 | # Autoenv 19 | .env 20 | # Direnv 21 | .envrc 22 | # PyCharm 23 | .idea 24 | 25 | # Distribution / packaging 26 | *.egg-info/ 27 | *.eggs/ 28 | 29 | # Macos 30 | *.DS_Store 31 | 32 | # Celery 33 | celerybeat-schedule.* 34 | 35 | # pytest-profiling 36 | prof/ 37 | -------------------------------------------------------------------------------- /.pre-commit-config.yaml: -------------------------------------------------------------------------------- 1 | exclude: > 2 | (?x)^( 3 | docs| 4 | Makefile 5 | ) 6 | 7 | repos: 8 | 9 | - repo: https://github.com/pre-commit/pre-commit-hooks 10 | sha: "v0.7.1" 11 | hooks: 12 | - id: trailing-whitespace 13 | - id: end-of-file-fixer 14 | - id: check-merge-conflict 15 | - id: debug-statements 16 | language: python 17 | language_version: python3 18 | - id: requirements-txt-fixer 19 | - id: name-tests-test 20 | args: ['--django'] 21 | 22 | - repo: https://gitlab.com/pycqa/flake8 23 | rev: "3.7.7" 24 | hooks: 25 | - id: flake8 26 | name: flake8 27 | language: python 28 | files: \.py$ 29 | language_version: python3 30 | exclude: tests 31 | additional_dependencies: ['flake8-builtins'] 32 | 33 | - repo: https://github.com/ambv/black 34 | rev: stable 35 | hooks: 36 | - id: black 37 | language_version: python3.6 38 | args: [--line-length=79] 39 | -------------------------------------------------------------------------------- /.travis.yml: -------------------------------------------------------------------------------- 1 | language: python 2 | python: 3 | - 3.6 4 | install: 5 | - pip install -U pip wheel 6 | - pip install -U -r requirements-dev.txt 7 | - pip install . 8 | cache: 9 | directories: 10 | - "$HOME/.cache/pip" 11 | stages: 12 | - test 13 | - linter 14 | - name: deploy 15 | if: tag IS present 16 | jobs: 17 | include: 18 | - stage: test 19 | name: Tests 20 | script: pytest --cov-report=term-missing --cov=mimics 21 | after_success: 22 | - codecov 23 | - stage: linter 24 | name: Linter 25 | script: pre-commit run --all-files --show-diff-on-failure 26 | - stage: deploy 27 | name: PyPI Deploy 28 | script: skip 29 | install: skip 30 | before_install: skip 31 | deploy: 32 | skip_cleanup: true 33 | provider: pypi 34 | distributions: sdist bdist_wheel 35 | user: maartendp 36 | on: 37 | tags: true 38 | repo: maarten-dp/mimics 39 | password: 40 | secure: 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 41 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | 2 | MIT License 3 | 4 | Copyright (c) 2019, maarten-dp 5 | 6 | Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: 7 | 8 | The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. 9 | 10 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 11 | 12 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | [![Build Status](https://travis-ci.com/maarten-dp/mimics.svg?branch=master)](https://travis-ci.com/maarten-dp/mimics) 2 | [![codecov](https://codecov.io/gh/maarten-dp/mimics/branch/master/graph/badge.svg?token=PBYN5VAJVZ)](https://codecov.io/gh/maarten-dp/mimics) 3 | [![PyPI version](https://badge.fury.io/py/mimics.svg)](https://pypi.org/project/mimics/) 4 | 5 | # Introduction 6 | 7 | Mimic is a tool with the intention to defer actions done on objects or classes. These actions can then be executed at a later date. It's main goal is to solve the chicken-and-egg design conundrum. 8 | 9 | **When you find yourself in a chicken-and-egg situation within your own code, it's most likely attributed to a sub-optimal project design. 10 | If this is the case, it's probably advisable to rethink your project structure.** 11 | 12 | Sometimes, though, when working with 3rd party libraries, you just don't have the choice, and the design of one library does not mesh with that of another. 13 | Out of spite (I'm looking at you \), I started writing this library so that I had control over "when" I initialized "what", while being able to do it in a controlled local scope without losing the ability to use global definitions. 14 | 15 | **BIG FAT DISCLAIMER**: I wouldn't use this lib in production code, not in its current state at least :) It needs some more battle testing before I can comfortably say it's stable. Feel free to contribute to this battle testing. 16 | 17 | # Quickstart 18 | 19 | The core of this library is the `Deferred` object, that basically behaves like a mock object. The only difference is that the `Deferred` object does not have reserved names, so you can do literally ***any*** operation on it. 20 | 21 | Of course, that means that you, the user, won't be able to use this deferred object as the driver. For this we'll need a handler object that set things in motion, and ties things together when needed. 22 | 23 | ```python 24 | from mimics import Mimic 25 | 26 | # Make the handler object 27 | mimic = Mimic() 28 | # Make an object, using the factory on the handler object, that will record all actions 29 | husk = mimic.husk() 30 | 31 | # Do the deferred operations you want to do 32 | result = husk + 3 33 | 34 | # Replay anything done on the deferred object onto another object 35 | mimic.absorb(husk).as_being(5) 36 | # Doing an additional `is True` to ensure to result is a boolean and not a deferred object 37 | # (because, yes, even these actions are deferred before playing) 38 | assert (result == 8) is True 39 | ``` 40 | 41 | # A more elaborate example 42 | This example won't make much sense, as Flask-SQLAlchemy plays quite nicely when it comes to having control over the local scope while still performing global actions, but I thought it was a nice example of what the library is capable of. Here we'll defer the creation, initialization and persistence of an SQLAlchemy model. 43 | 44 | Once we've done all we wanted, we can play it whenever it suits us best. 45 | 46 | ```python 47 | # Make the handler and deferred object 48 | mimic = Mimic() 49 | husk = mimic.husk() 50 | 51 | # Defer the making of an SQLA model using the deferred object 52 | class MyModel(husk.Model): 53 | id = husk.Column(husk.Integer, primary_key=True) 54 | name = husk.Column(husk.String(255), nullable=False, unique=True) 55 | 56 | # Defer the db creation 57 | husk.create_all() 58 | # Defer the initialization and persisting of an instance 59 | my_model = MyModel(name="test") 60 | husk.session.add(my_model) 61 | husk.session.commit() 62 | 63 | # Make the actual SQLA db object 64 | app = Flask(__name__) 65 | app.config['SQLALCHEMY_DATABASE_URI'] = "sqlite:///:memory:" 66 | app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False 67 | db = SQLAlchemy(app) 68 | 69 | # Replay deferred actions as being the db 70 | mimic.absorb(husk).as_being(db) 71 | 72 | # Verify it worked 73 | models = MyModel.query.all() 74 | assert len(models) == 1 75 | assert models[0].name == "test" 76 | ``` 77 | 78 | # How it works 79 | As mentioned above, the entire library revolves around the `Deferred` object. Due to being able to do, well, almost anything with this object, it's important that you don't initialize a deferred object yourself (unless you know what you're doing). It's important that you make an instance of this class through the factory method that is available on a `Mimic` instance. 80 | 81 | Basically the `Deferred` object can be in two states: 82 | - suspended 83 | - unsuspended 84 | 85 | A shocker, I know. Whenever the `Deferred` object is suspended, it will record any action done upon it. Whenever an attribute is accessed, a method is called, or anything that returns a value, it will create and return a new instance of the `Deferred` object, that in turn also records actions done with it. 86 | 87 | Once you're ready to play your deferred actions, bringing it to an unsuspended state, the recorded actions will be re-played on the chosen object. From then on, the spawned deferred objects will work as a proxy that forwards any request to the subject it's related to. 88 | 89 | # Pitfalls 90 | ## Proxy object 91 | Because this library is not doing black magic (or at least, not an aweful lot 😉), it's important to know that any subject that the `Deferred` object shadows, will never ***truly*** be itself after unsuspending. We're not manipulating the virtual memory, manipulating local and global variables or patching imported modules (mind you, I've thought about it), as that distorts readability and the ability to follow the exection flow. 92 | 93 | While it may look like you're interacting with the subject itself, you'll always be interacting with a proxy object that looks and feels like its subject. As such, some kinks might pop up in certain cases (cfr. BIG FAT DISCLAIMER). 94 | 95 | ## The Deferred object's limits 96 | It's important to note that only operations performed ***on*** deferred objects are allowed. Performing operations ***with*** deferred objects will go horribly wrong. 97 | 98 | For instance 99 | ```python 100 | husk = Mimic().husk() 101 | result = 5 + husk 102 | ``` 103 | will result in a TypeError 104 | -------------------------------------------------------------------------------- /mimics/__init__.py: -------------------------------------------------------------------------------- 1 | from .deferred import Deferred 2 | from .inspect import TrueSight 3 | from .record import Recorder 4 | 5 | 6 | class StasisTrap: 7 | """ 8 | Used for deferring a known object or class 9 | """ 10 | 11 | def __init__(self): 12 | self.recorders = {} 13 | 14 | def suspend(self, subject): 15 | recorder = Recorder() 16 | deferred = Deferred(recorder, subject) 17 | self.recorders[id(deferred)] = recorder 18 | return deferred 19 | 20 | def release(self, subject): 21 | recorder = self.recorders[id(subject)] 22 | for deferred in recorder.deferred_objects: 23 | deferred.suspended = False 24 | recorder.play() 25 | 26 | 27 | class Mimic: 28 | """ 29 | Used for deferring an unknown object or class 30 | """ 31 | 32 | def __init__(self): 33 | self.recorders = {} 34 | 35 | def husk(self): 36 | recorder = Recorder() 37 | deferred = Deferred(recorder) 38 | self.recorders[id(deferred)] = recorder 39 | return deferred 40 | 41 | def absorb(self, husk): 42 | recorder = self.recorders[id(husk)] 43 | return FedMimic(recorder, husk) 44 | 45 | 46 | class FedMimic: 47 | """ 48 | A Mimic becomes a FedMimic once the object or class becomes known 49 | """ 50 | 51 | def __init__(self, recorder, husk): 52 | self.recorder = recorder 53 | self.deferred = TrueSight(husk) 54 | 55 | def as_being(self, subject): 56 | self.deferred.subject = subject 57 | for deferred in self.recorder.deferred_objects: 58 | deferred.suspended = False 59 | self.recorder.play() 60 | -------------------------------------------------------------------------------- /mimics/constants.py: -------------------------------------------------------------------------------- 1 | MAGIC_METHODS = [ 2 | "__add__", 3 | "__sub__", 4 | "__mul__", 5 | "__floordiv__", 6 | "__div__", 7 | "__mod__", 8 | "__pow__", 9 | "__lshift__", 10 | "__rshift__", 11 | "__and__", 12 | "__xor__", 13 | "__or__", 14 | "__iadd__", 15 | "__isub__", 16 | "__imul__", 17 | "__idiv__", 18 | "__ifloordiv__", 19 | "__imod__", 20 | "__ipow__", 21 | "__ilshift__", 22 | "__irshift__", 23 | "__iand__", 24 | "__ixor__", 25 | "__ior__", 26 | "__neg__", 27 | "__pos__", 28 | "__abs__", 29 | "__invert__", 30 | "__complex__", 31 | "__int__", 32 | "__long__", 33 | "__float__", 34 | "__oct__", 35 | "__hex__", 36 | "__lt__", 37 | "__le__", 38 | "__eq__", 39 | "__ne__", 40 | "__ge__", 41 | "__gt__", 42 | "__hash__", 43 | ] 44 | -------------------------------------------------------------------------------- /mimics/deferred.py: -------------------------------------------------------------------------------- 1 | from functools import wraps 2 | 3 | from .inspect import TrueSight, accessible 4 | from .constants import MAGIC_METHODS 5 | from .record import record, Record 6 | 7 | 8 | def reroute_or_defer(fn): 9 | @wraps(fn) 10 | def decorator(self, *args, **kwargs): 11 | if not self.suspended: 12 | return getattr(self.subject, fn)(*args, **kwargs) 13 | return Deferred(self.recorder) 14 | 15 | decorator.__name__ = fn 16 | return accessible(record(decorator)) 17 | 18 | 19 | class DeferredMeta(type): 20 | def __new__(cls, name, bases, attrs): 21 | overload = {mm: reroute_or_defer(mm) for mm in MAGIC_METHODS} 22 | overload.update(attrs) 23 | return super().__new__(cls, name, bases, overload) 24 | 25 | 26 | class Deferred(metaclass=DeferredMeta): 27 | def __new__(cls, *args, **kwargs): 28 | # Acting as class creating an instance 29 | if len(args) <= 2: 30 | return super().__new__(cls) 31 | 32 | # Acting as metaclass creating a class 33 | name, bases, attrs = args 34 | deferred_obj = TrueSight([d for d in bases if isinstance(d, cls)][0]) 35 | klass = Deferred(deferred_obj.recorder) 36 | 37 | record = Record(deferred_obj, "subclassed", args, kwargs, klass) 38 | deferred_obj.recorder.record(record) 39 | 40 | return klass 41 | 42 | @accessible 43 | def __init__(self, *args, **kwargs): 44 | if not hasattr(self, "recorder"): 45 | self._init_as_instance(*args, **kwargs) 46 | 47 | @accessible 48 | def _init_as_instance(self, recorder, subject=None): 49 | self.recorder = recorder 50 | self.subject = subject 51 | self.suspended = True 52 | self.cache = {} 53 | 54 | recorder.deferred_objects.append(self) 55 | 56 | @accessible 57 | @record 58 | def __getattribute__(self, key): 59 | if not self.suspended: 60 | return getattr(self.subject, key) 61 | 62 | if key in self.cache: 63 | return self.cache[key] 64 | 65 | return_val = Deferred(self.recorder) 66 | self.cache[key] = return_val 67 | return return_val 68 | 69 | @accessible 70 | @record 71 | def __call__(self, *args, **kwargs): 72 | if not self.suspended: 73 | return self.subject(*args, **kwargs) 74 | return Deferred(self.recorder) 75 | 76 | @accessible 77 | def __str__(self): 78 | if not self.suspended: 79 | return str(self.subject) 80 | return str(self) 81 | 82 | @accessible 83 | def __repr__(self): 84 | if not self.suspended: 85 | return "".format(repr(self.subject)) 86 | return object.__repr__(self.obj) 87 | 88 | @accessible 89 | def __instancecheck__(self, inst): 90 | if not self.suspended: 91 | return self.subject.__instancecheck__(inst) 92 | return self.__class__.__instancecheck__(inst) 93 | -------------------------------------------------------------------------------- /mimics/inspect.py: -------------------------------------------------------------------------------- 1 | from functools import wraps 2 | import inspect 3 | 4 | 5 | WHITELISTED = [ 6 | "recorder", 7 | "subject", 8 | "suspended", 9 | "cache", 10 | "_init_as_instance", 11 | ] 12 | 13 | 14 | def accessible(fn): 15 | @wraps(fn) 16 | def decorator(self, *args, **kwargs): 17 | return fn(TrueSight(self), *args, **kwargs) 18 | 19 | return decorator 20 | 21 | 22 | class TrueSight: 23 | def __init__(self, obj): 24 | object.__setattr__(self, "obj", obj) 25 | 26 | def __getattr__(self, key): 27 | if key not in WHITELISTED: 28 | raise AttributeError(f"Deferred has no attribute {key}") 29 | return object.__getattribute__(self.obj, key) 30 | 31 | def __setattr__(self, key, value): 32 | setattr(self.obj, key, value) 33 | 34 | def get(self, key): 35 | return self.__getattr__(key) 36 | 37 | def __repr__(self): 38 | val = object.__repr__(self.obj) 39 | return f"TrueSight object for {val}" 40 | 41 | def is_deferred_object(self): 42 | cls_name = object.__getattribute__(self.obj, "__class__").__name__ 43 | return "Deferred" in cls_name 44 | 45 | 46 | def shape_shift(target, destination): 47 | if not TrueSight(destination).is_deferred_object(): 48 | return 49 | 50 | def reroute(member, subject): 51 | def decorator(self, *args, **kwargs): 52 | return getattr(subject, member)(*args, **kwargs) 53 | 54 | return decorator 55 | 56 | def reroute_to_fn(fn): 57 | def decorator(self, *args, **kwargs): 58 | return fn(target, *args, **kwargs) 59 | 60 | return decorator 61 | 62 | def reroute_direct(fn): 63 | def decorator(self, *args, **kwargs): 64 | return fn(*args, **kwargs) 65 | 66 | return decorator 67 | 68 | methods = {} 69 | candidate = target.__class__ 70 | if inspect.isclass(target): 71 | candidate = target 72 | methods["__call__"] = reroute_direct(target) 73 | methods["__instancecheck__"] = reroute_direct(target.__instancecheck__) 74 | 75 | members = dict(inspect.getmembers(candidate)) 76 | for member_name, member in members.items(): 77 | if callable(member): 78 | methods[member_name] = reroute(member_name, target) 79 | 80 | methods["__getattribute__"] = reroute_to_fn(getattr) 81 | methods["__repr__"] = reroute_to_fn(repr) 82 | methods["__str__"] = reroute_to_fn(str) 83 | methods["__setattr__"] = reroute_to_fn(setattr) 84 | 85 | Proxy = type("Proxy", tuple(), methods) 86 | destination.__class__ = Proxy 87 | -------------------------------------------------------------------------------- /mimics/record.py: -------------------------------------------------------------------------------- 1 | from functools import wraps 2 | 3 | from .inspect import TrueSight, shape_shift, WHITELISTED 4 | 5 | 6 | # If I'm raised, I probably didn't use a TrueSight obj where I needed to 7 | def ensure_truesight(_accessed, *args, **kwargs): 8 | if not _accessed == "__getattr__": 9 | return 10 | arg = args[0] 11 | if arg in WHITELISTED: 12 | raise Exception("Investigate me") 13 | 14 | 15 | def record(fn): 16 | @wraps(fn) 17 | def decorator(self, *args, **kwargs): 18 | return_deferred = fn(self, *args, **kwargs) 19 | ensure_truesight(fn.__name__, *args, **kwargs) 20 | if self.suspended: 21 | record = Record(self, fn.__name__, args, kwargs, return_deferred) 22 | self.recorder.record(record) 23 | return return_deferred 24 | 25 | return decorator 26 | 27 | 28 | class Record: 29 | def __init__(self, deferred, action, args, kwargs, return_deferred): 30 | action_handlers = { 31 | "__call__": self._handle_call, 32 | "subclassed": self._handle_subclass, 33 | } 34 | 35 | self.deferred = deferred 36 | self.action = action 37 | self.handler = action_handlers.get(action, self._handle_default) 38 | self.args = args 39 | self.kwargs = kwargs 40 | self.return_deferred = TrueSight(return_deferred) 41 | 42 | @property 43 | def subject(self): 44 | return self.deferred.subject 45 | 46 | def perform(self): 47 | result = self.handler() 48 | is_checkable = hasattr(self.return_deferred, "is_deferred_object") 49 | is_deferred = self.return_deferred.is_deferred_object() 50 | if is_checkable and is_deferred: 51 | self.return_deferred.subject = result 52 | shape_shift(self.return_deferred.subject, self.return_deferred.obj) 53 | 54 | def _handle_call(self): 55 | return self.subject(*self.args, **self.kwargs) 56 | 57 | def _handle_subclass(self): 58 | name, bases, attrs = self.args 59 | 60 | bases = list(bases) 61 | bases[bases.index(self.deferred.obj)] = self.deferred.subject 62 | 63 | return type(name, tuple(bases), attrs) 64 | 65 | def _handle_default(self): 66 | action = getattr(self.subject, self.action) 67 | return action(*self.args, **self.kwargs) 68 | 69 | def __repr__(self): 70 | return ( 71 | f"Deferred: {self.deferred}\n" 72 | f"Subject: {self.subject}\n" 73 | f"Action: {self.action}\n" 74 | f"Args: {self.args}\n" 75 | f"Kwargs: {self.kwargs}\n" 76 | f"return_deferred: {self.return_deferred}\n" 77 | ) 78 | 79 | 80 | class Recorder: 81 | def __init__(self): 82 | self.records = [] 83 | self.deferred_objects = [] 84 | 85 | def record(self, record): 86 | self.records.append(record) 87 | 88 | def play(self): 89 | for record in self.records: 90 | record.perform() 91 | -------------------------------------------------------------------------------- /requirements-dev.txt: -------------------------------------------------------------------------------- 1 | celery==5.0.5 2 | Flask-SQLAlchemy==2.5.1 3 | pbr>=3.0 4 | pre-commit==2.13.0 5 | pytest==6.2.4 6 | pytest-celery==0.0.0 7 | pytest-cov 8 | -------------------------------------------------------------------------------- /setup.cfg: -------------------------------------------------------------------------------- 1 | [metadata] 2 | name = mimics 3 | author = Maarten De Paepe 4 | author-email = "maarten.de.paepe@gmail.com" 5 | summary = Small tool for deferring actions and operations on objects and classes 6 | description-file = README.md 7 | long-description-content-type = text/markdown 8 | home-page = https://github.com/maarten-dp/mimics 9 | classifier = 10 | Development Status :: 4 - Beta 11 | Operating System :: MacOS :: MacOS X 12 | Operating System :: Microsoft :: Windows 13 | Operating System :: POSIX 14 | 15 | License :: OSI Approved :: MIT License 16 | 17 | Programming Language :: Python 18 | Programming Language :: Python :: 3.6 19 | 20 | [files] 21 | packages = mimics 22 | 23 | [pbr] 24 | warnerrors = True 25 | 26 | [wheel] 27 | universal = 1 28 | 29 | [flake8] 30 | exclude = */migrations/*,*/south_migrations/* 31 | max-line-length = 100 32 | ignore = 33 | # W503: line break before binary operator 34 | W503, 35 | 36 | # W504: line break after binary operator 37 | W504, 38 | 39 | [isort] 40 | line_length = 100 41 | 42 | [yapf] 43 | indent_dictionary_value = true 44 | allow_split_before_dict_value = false 45 | 46 | [tool:pytest] 47 | norecursedirs = 48 | .git 49 | .tox 50 | .env 51 | .eggs 52 | .cache 53 | dist 54 | build 55 | south_migrations 56 | migrations 57 | chunk_scripts 58 | python_files = 59 | test_*.py 60 | *_test.py 61 | tests.py 62 | -------------------------------------------------------------------------------- /setup.py: -------------------------------------------------------------------------------- 1 | from setuptools import setup 2 | 3 | setup(setup_requires=["pbr"], pbr=True) 4 | -------------------------------------------------------------------------------- /tests/conftest.py: -------------------------------------------------------------------------------- 1 | from mimics import StasisTrap 2 | import pytest 3 | 4 | 5 | @pytest.fixture 6 | def trap(): 7 | return StasisTrap() 8 | -------------------------------------------------------------------------------- /tests/test_defer_class_definition.py: -------------------------------------------------------------------------------- 1 | from mimics import Mimic 2 | 3 | 4 | def test_it_can_defer_class_definition(): 5 | mimic = Mimic() 6 | Husk = mimic.husk() 7 | 8 | class TestDeferred(Husk): 9 | def do_the_thing(self): 10 | return self.thing 11 | 12 | zhu_li = TestDeferred("doing the thing") 13 | dont_look_yet = zhu_li.do_the_thing() 14 | 15 | class Test: 16 | def __init__(self, thing): 17 | self.thing = thing 18 | 19 | mimic.absorb(Husk).as_being(Test) 20 | 21 | assert dont_look_yet == "doing the thing" 22 | -------------------------------------------------------------------------------- /tests/test_deferred.py: -------------------------------------------------------------------------------- 1 | import operator 2 | 3 | import pytest 4 | 5 | from mimics import Deferred, TrueSight, Recorder, Mimic 6 | 7 | 8 | def test_it_can_defer_a_funtion_call(trap): 9 | def some_function(param1, param2): 10 | return f"{param1} {param2}" 11 | 12 | some_function = trap.suspend(some_function) 13 | 14 | result = some_function("bomp", "bamp") 15 | 16 | assert result != "bomp bamp" 17 | trap.release(some_function) 18 | assert result == "bomp bamp" 19 | 20 | 21 | def test_it_can_defer_an_instanced_function_call(trap): 22 | class Test: 23 | def some_function(self, param1, param2): 24 | return f"{self.__class__.__name__} {param1} {param2}" 25 | 26 | Test = trap.suspend(Test) 27 | 28 | test = Test() 29 | result = test.some_function("bomp", "bamp") 30 | 31 | assert result != "Test bomp bamp" 32 | trap.release(Test) 33 | assert result == "Test bomp bamp" 34 | 35 | 36 | def test_it_can_defer_a_decorator(trap): 37 | def some_decorator(fn): 38 | def decorator(*args, **kwargs): 39 | injected = "I'm injected!" 40 | return fn(injected, *args, **kwargs) 41 | 42 | return decorator 43 | 44 | some_decorator = trap.suspend(some_decorator) 45 | 46 | @some_decorator 47 | def some_function(injected, param1): 48 | return f"{injected} => {param1}" 49 | 50 | result = some_function("yuck") 51 | 52 | assert result != "I'm injected! => yuck" 53 | trap.release(some_decorator) 54 | assert result == "I'm injected! => yuck" 55 | 56 | 57 | def test_it_can_defer_second_level_decorator(trap): 58 | class Test: 59 | def some_decorator(self, fn): 60 | def decorator(*args, **kwargs): 61 | injected = f"I'm injected from {self.__class__.__name__}!" 62 | return fn(injected, *args, **kwargs) 63 | 64 | return decorator 65 | 66 | Test = trap.suspend(Test) 67 | test = Test() 68 | 69 | @test.some_decorator 70 | def some_function(injected, param1): 71 | return f"{injected} => {param1}" 72 | 73 | result = some_function("yuck") 74 | 75 | assert result != "I'm injected from Test! => yuck" 76 | trap.release(Test) 77 | assert result == "I'm injected from Test! => yuck" 78 | 79 | 80 | def test_it_can_format_a_suspended_result(): 81 | deferred = Deferred(Recorder(), "SomeString") 82 | handle = TrueSight(deferred) 83 | handle.suspended = False 84 | 85 | assert f"{deferred}!" == "SomeString!" 86 | 87 | 88 | def test_it_can_pose_as_an_instance(trap): 89 | class Test: 90 | pass 91 | 92 | DeferredTest = trap.suspend(Test) 93 | 94 | test = DeferredTest() 95 | # Should this be an instance of DeferredTest? 96 | assert isinstance(test, Deferred) 97 | trap.release(DeferredTest) 98 | assert isinstance(test, Test) 99 | 100 | 101 | def test_it_can_suspend_an_initialization_with_parameters(trap): 102 | class Test: 103 | def __init__(self, param1): 104 | self.param1 = param1 105 | 106 | Test = trap.suspend(Test) 107 | test = Test("some param") 108 | 109 | assert test.param1 != "some param" 110 | trap.release(Test) 111 | assert test.param1 == "some param" 112 | 113 | 114 | @pytest.mark.parametrize( 115 | "op,result", 116 | [ 117 | (operator.add, 7), 118 | (operator.sub, -1), 119 | (operator.mul, 12), 120 | (operator.pow, 81), 121 | (operator.floordiv, 0), 122 | (operator.mod, 3), 123 | (operator.and_, 0), 124 | (operator.or_, 7), 125 | (operator.xor, 7), 126 | (operator.lshift, 48), 127 | (operator.rshift, 0), 128 | (operator.eq, False), 129 | (operator.ne, True), 130 | (operator.ge, False), 131 | (operator.gt, False), 132 | (operator.le, True), 133 | (operator.lt, True), 134 | ], 135 | ) 136 | def test_it_can_defer_operators(trap, op, result): 137 | var = 3 138 | var = trap.suspend(var) 139 | result = op(var, 4) 140 | 141 | assert result != result 142 | trap.release(var) 143 | assert result == result 144 | 145 | 146 | @pytest.mark.skip("Have a look at this later") 147 | def test_it_can_defer_operation_assignments(trap): 148 | my_number = 4 149 | my_number = trap.suspend(my_number) 150 | my_number += 5 151 | trap.release(my_number) 152 | assert my_number == 9 153 | 154 | 155 | def test_a_mimic_can_solve_chicken_and_egg(): 156 | class A: 157 | def __init__(self, b): 158 | self.b = b 159 | 160 | class B: 161 | def __init__(self, a): 162 | self.a = a 163 | 164 | mimic = Mimic() 165 | husk = mimic.husk() 166 | b = B(husk) 167 | a = A(b) 168 | mimic.absorb(husk).as_being(a) 169 | 170 | assert b.a == a 171 | assert a.b == b 172 | -------------------------------------------------------------------------------- /tests/test_use_cases.py: -------------------------------------------------------------------------------- 1 | from mimics import Mimic 2 | from flask import Flask 3 | from flask_sqlalchemy import SQLAlchemy 4 | 5 | 6 | def test_vanilla_celery(celery_app, celery_worker): 7 | # Vanilla celery test as found at 8 | # https://docs.celeryproject.org/en/stable/userguide/testing.html#fixtures 9 | @celery_app.task 10 | def mul(x, y): 11 | return x * y 12 | 13 | celery_worker.reload() 14 | 15 | assert mul.delay(4, 4).get(timeout=10) == 16 16 | 17 | 18 | def test_mimicked_celery(celery_app, celery_worker): 19 | mimic = Mimic() 20 | celery_husk = mimic.husk() 21 | 22 | @celery_husk.task 23 | def mul(x, y): 24 | return x * y 25 | 26 | celery_app = mimic.absorb(celery_husk).as_being(celery_app) 27 | 28 | celery_worker.reload() 29 | 30 | assert mul.delay(4, 4).get(timeout=10) == 16 31 | 32 | 33 | def test_it_can_mimic_flask_sqlalchemy(): 34 | mimic = Mimic() 35 | husk = mimic.husk() 36 | 37 | class MyModel(husk.Model): 38 | id = husk.Column(husk.Integer, primary_key=True) 39 | name = husk.Column(husk.String(255), nullable=False, unique=True) 40 | 41 | husk.create_all() 42 | my_model = MyModel(name="test") 43 | husk.session.add(my_model) 44 | husk.session.commit() 45 | 46 | app = Flask(__name__) 47 | app.config["SQLALCHEMY_DATABASE_URI"] = "sqlite:///:memory:" 48 | app.config["SQLALCHEMY_TRACK_MODIFICATIONS"] = False 49 | db = SQLAlchemy(app) 50 | 51 | mimic.absorb(husk).as_being(db) 52 | 53 | models = MyModel.query.all() 54 | assert len(models) == 1 55 | assert models[0].name == "test" 56 | --------------------------------------------------------------------------------