Python Patterns

python-patterns - A collection of design patterns and idioms in Python (With tests!).

Current Patterns

Creational Patterns:

Pattern	Description	Tests
Abstract Factory	use a generic function with specific factories	test
Builder	instead of using multiple constructors, builder receives parameters and returns constructed objects	test
Factory Method	delegate a specialized function/method to create instances	test
Prototype	use a factory and clones of a prototype for new instances (if instantiation is expensive)	test
Singleton	Ensures that the class has only one instance, and provides a global access point to it.	test

Structural Patterns:

Pattern	Description	Tests
Adapter	converts the interface of one class to the interface of another that clients expect.	test
Bridge	a client-provider middleman to soften interface changes	test
Composite	lets clients treat individual objects and compositions uniformly	test
Decorator	wrap functionality with other functionality in order to affect outputs	test
Facade	use one class as an API to a number of others	test
Flyweight	transparently reuse existing instances of objects with similar/identical state	test
Proxy	an object funnels operations to something else	test

Behavior Patterns:

Pattern	Description	Tests
Blackboard	architectural model, assemble different sub-system knowledge to build a solution, AI approach - non gang of four pattern.	test
chain_of_responsibility	apply a chain of successive handlers to try and process the data.	test
command	bundle a command and arguments to call later.	test
interpreter	a behavioral design pattern that solves a frequently encountered but subject to change problem.	test
iterator	traverse a container and access the container's elements.	test
mediator	an object that knows how to connect other objects and act as a proxy.	test
memento	generate an opaque token that can be used to go back to a previous state.	test
observer	provide a callback for notification of events/changes to data.	test
state	logic is organized into a discrete number of potential states and the next state that can be transitioned to.	test
strategy	selectable operations over the same data.	test
template_method	defines the basis of the algorithm and allows subclasses to override some of the steps in the algorithm, without changing its structure as a whole.	test
visitor	invoke a callback for all items of a collection.	test

Help:

Requirements:

python 3.6+

For run tests:

pytest

pip3 install pytest
pytest -v

pytest-cov

pip3 install pytest-cov
pytest --cov

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