assertify

assertify -- assert or (ver)ify -- is a Flexible, and Extendable python3.6+ library for evaluating an expression by returning False or raising an AssertionError or the given Exception if the expression is invalid.

Key Features:

• Easy: Designed to make it easy to evaluate an expression and return True/False or raise an AssertionError or Exception.
• Great Developer Experience: Being fully typed makes it great for editor support.
• There is More!!!:
  • unittest_assertions: Assertify is built on top of the unittest_assertions, which is a library that converts the assertions from unittest to standalone assertions.

Installation

pip install assertify

Example

raises an appropriate exception by default.

Exception Example

AssertifyIsInstance will raise a TypeError by default, but you can also specify any other type of exception.

from assertifiers.identity import AssertifyIsInstance

is_instance = AssertifyIsInstance()
is_instance("example str", int)  # raise TypeError("'example str' is not an instance of <class 'int'>")

Assertion Example

Specify AssertionError to be raised

from assertifiers.identity import AssertifyIsInstance

is_instance = AssertifyIsInstance(raises=AssertionError)
is_instance("example str", int)  # raise AssertionError("'example str' is not an instance of <class 'int'>")

Boolean Example

If raises=None assertify will return a Boolean.

from assertifiers.identity import AssertifyIsInstance

is_instance = AssertifyIsInstance(raises=None)
print(is_instance("example str", int))  # False

Predicate (Partial Function) Example

from functools import partial
from assertifiers.identity import AssertifyIsInstances

is_instance = AssertifyIsInstances(must_be_instance_of=any)
predicate_is_instance = partial(is_instance,classes=[int,float])
print(predicate_is_instance(obj=7.62)) # True

Assertifiers

Comparison

Assertifier	Expression	raises
AssertifyEqual	assertify first == second	ValueError
AssertifyNotEqual	assertify first != Second	ValueError
AssertifyAlmostEqual	assertify first ~= second	ValueError
AssertifyNotAlmostEqual	assertify first !~= second	ValueError
AssertifyCountEqual	assertify len(first) == len(second)	ValueError
AssertifyMultilineEqual	assertify first.splitlines() == second.splitlines()	ValueError
AssertifySequenceEqual	assertify seq1 == seq2	ValueError
AssertifyListEqual	assertify list1 == list2	ValueError
AssertifyTupleEqual	assertify tuple1 == tuple2	ValueError
AssertifySetEqual	assertify set1 == set2	ValueError
AssertifyDictEqual	assertify dict1 == dict2	ValueError
AssertifyLess	assertify a < b	ValueError
AssertifyLessEqual	assertify a <= b	ValueError
AssertifyGreater	assertify a > b	ValueError
AssertifyGreater	assertify a >= b	ValueError

Container

Assertifier	Expression	raises
AssertifyIn	assertify member in container	ValueError
AssertifyNotIn	assertify member not in container	ValueError

Control

Assertifier	Expression	raises
AssertifyRaises	assertify function raises expected_exception	ValueError
AssertifyWarns	assertify function warns expected_warning	ValueError
AssertifyLogs	assertify logger(level)	ValueError

Identity

Assertifier	Expression	raises
AssertifyIs	assertify exp1 is exp2	ValueError
AssertifyIsNot	assertify exp1 is not exp2	ValueError
AssertifyIsNone	assertify obj is None	ValueError
AssertifyIsNotNone	assertify obj is not None	ValueError
AssertifyIsInstance	assertify isinstance(obj,class)	TypeError
AssertifyIsInstances	assertify isinstance(obj,cls) for cls in classes	TypeError
AssertifyIsNotInstance	assertify not isinstance(obj,class)	TypeError
AssertifyIsNotInstances	assertify not isinstance(obj,cls) for cls in classes	TypeError

Logic

Assertifier	Expression	raises
AssertifyTrue	assertify expr is True	ValueError
AssertifyFalse	assertify expr is False	ValueError

Regex

Assertifier	Expression	raises
AssertifyRaisesRegex	assertify expected_regex in expected_exception_message	ValueError
AssertifyWarnsRegex	assertify expected_regex in expected_warning_message	ValueError
AssertifyRegex	assertify text in expected_regex	ValueError
AssertifyNotRegex	assertify text not in expected_regex	ValueError