out.txt

Using /validators/faker/.eggs/UkPostcodeParser-1.1.2-py3.7.egg
Searching for validators@ https://github.com/kingbuzzman/validators.git#egg=validators-0.13.0
Best match: validators 0.12.6
Processing validators-0.12.6-py3.7.egg

setup.py

# Full source can be found here.
# https://github.com/kingbuzzman/faker/commit/20f69082714fae2a60d356f4c63a061ce99a975e
...

setup(
    name='Faker',
    version=VERSION,
    description="Faker is a Python package that generates fake data for you.",
    long_description=README,
    entry_points={
        'console_scripts': ['faker=faker.cli:execute_from_command_line'],
    },
    ...
    tests_require=[
        "validators@https://github.com/kingbuzzman/validators.git#egg=validators-0.13.0",  # TODO: this will change  # noqa
        "ukpostcodeparser>=1.1.1",
        "mock",
        "pytest>=3.8.0,<3.9",
        "more-itertools<6.0.0",#7921be1537eac1e97bc40179a57f0
        "random2==1.0.1",
        "freezegun==0.3.11",
    ],
    extras_require={
        ':python_version<"3.3"': [
            'ipaddress',
        ],
    },
)

Easiest way of testing this is running:

docker run -it --rm python:3.7 bash -c "git clone https://github.com/kingbuzzman/faker.git; cd faker; pip install -e .; python setup.py test"

You will find the Best match: validators 0.12.6 and the final error as:

ImportError while importing test module '/faker/tests/providers/test_ssn.py'.
Hint: make sure your test modules/packages have valid Python names.
Traceback:
tests/providers/test_ssn.py:12: in <module>
    from validators.i18n.es import es_cif as is_cif, es_nif as is_nif, es_nie as is_nie
E   ModuleNotFoundError: No module named 'validators.i18n.es'

Because these modules/functions are on 0.13.0 NOT 0.12.0