Trying to execute tests (following contribution guideline) fails with ModuleNotFoundError

[atodorov]

Following your contribution guide I did:

1. pip install -e . -r requirements/dev.txt inside a fresh venv
2. pre-commit install

Didn't see any errors. This is on Linux with Python 3.6. Then:

$ pytest
ImportError while loading conftest '/home/atodorov/private/repos/github/mlh/flask-sqlalchemy/tests/conftest.py'.
tests/conftest.py:6: in <module>
    from flask_sqlalchemy import SQLAlchemy
E   ModuleNotFoundError: No module named 'flask_sqlalchemy'

---

Expected Behavior

Tests would execute.

Actual Behavior

ModuleNotFoundError

Environment

• Python version: 3.6

tox also seemed to fail:

(mlh-flask-sqlalchemy) [atodorov@aero flask-sqlalchemy]$ tox
GLOB sdist-make: /home/atodorov/private/repos/github/mlh/flask-sqlalchemy/setup.py
py38 create: /home/atodorov/private/repos/github/mlh/flask-sqlalchemy/.tox/py38
SKIPPED: InterpreterNotFound: python3.8
py37 create: /home/atodorov/private/repos/github/mlh/flask-sqlalchemy/.tox/py37
SKIPPED: InterpreterNotFound: python3.7
py36 create: /home/atodorov/private/repos/github/mlh/flask-sqlalchemy/.tox/py36
py36 installdeps: -rrequirements/tests.txt
WARNING: Discarding $PYTHONPATH from environment, to override specify PYTHONPATH in 'passenv' in your configuration.
py36 inst: /home/atodorov/private/repos/github/mlh/flask-sqlalchemy/.tox/.tmp/package/1/Flask-SQLAlchemy-3.0.0.dev0.zip
WARNING: Discarding $PYTHONPATH from environment, to override specify PYTHONPATH in 'passenv' in your configuration.
ERROR: invocation failed (exit code 1), logfile: /home/atodorov/private/repos/github/mlh/flask-sqlalchemy/.tox/py36/log/py36-2.log
=============================================================== log start ================================================================
Processing ./.tox/.tmp/package/1/Flask-SQLAlchemy-3.0.0.dev0.zip
    ERROR: Command errored out with exit status 1:
     command: /home/atodorov/private/repos/github/mlh/flask-sqlalchemy/.tox/py36/bin/python -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-req-build-or6vzxsq/setup.py'"'"'; __file__='"'"'/tmp/pip-req-build-or6vzxsq/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' egg_info --egg-base /tmp/pip-pip-egg-info-_5xcx6_h
         cwd: /tmp/pip-req-build-or6vzxsq/
    Complete output (5 lines):
    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/tmp/pip-req-build-or6vzxsq/setup.py", line 5, in <module>
        with open("src/flask_sqlalchemy/__init__.py", encoding="utf8") as f:
    FileNotFoundError: [Errno 2] No such file or directory: 'src/flask_sqlalchemy/__init__.py'
    ----------------------------------------
ERROR: Command errored out with exit status 1: python setup.py egg_info Check the logs for full command output.
WARNING: You are using pip version 20.1.1; however, version 21.0.1 is available.
You should consider upgrading via the '/home/atodorov/private/repos/github/mlh/flask-sqlalchemy/.tox/py36/bin/python -m pip install --upgrade pip' command.

[davidism]

This is because pip's new resolver doesn't handle -e . -r file the same way as the old one. pypa/pip#8307 Instead, do pip install -r requirements/dev.txt && pip install -e ..

[davidism]

fixed in #911