visual studio code - ImportErrors and ModuleNotFoundError for python

Question

It seems like my system cannot access modules from other folders. For example, if i set my directory to

~/Downloads/principles_of_programming/object-oriented-programming/fibonacci 

and run

pytest tests/test_fibonacci.py

I get

==================================================== test session starts ===================================================== 
platform win32 -- Python 3.9.1, pytest-6.2.2, py-1.10.0, pluggy-0.13.1
rootdir: C:UsersRyanDownloadsprinciples_of_programmingobject-oriented-programming, configfile: setup.cfg
collected 0 items                                                                                                              

=================================================== no tests ran in 0.05s ==================================================== 
ERROR: file or directory not found: tests/test_fibonacci.py

If I change my directory to

~/Downloads/principles_of_programming/object-oriented-programming

and run the test as above I get

==================================================== test session starts ===================================================== 
platform win32 -- Python 3.9.1, pytest-6.2.2, py-1.10.0, pluggy-0.13.1
rootdir: C:UsersRyanDownloadsprinciples_of_programmingobject-oriented-programming, configfile: setup.cfg
collected 0 items / 1 error                                                                                                    

=========================================================== ERRORS =========================================================== 
__________________________________________ ERROR collecting tests/test_fibonacci.py __________________________________________ 
ImportError while importing test module 'C:UsersRyanDownloadsprinciples_of_programmingobject-oriented-programmingestsest_fibonacci.py'.
Hint: make sure your test modules/packages have valid Python names.
Traceback:
......AppDataLocalProgramsPythonPython39libimportlib\__init__.py:127: in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
testsest_fibonacci.py:1: in <module>
    from fibonacci import fib
E   ModuleNotFoundError: No module named 'fibonacci'
================================================== short test summary info =================================================== 
ERROR tests/test_fibonacci.py
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Interrupted: 1 error during collection !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 
====================================================== 1 error in 0.45s ====================================================== 

Error Output

question from:https://stackoverflow.com/questions/66057257/importerrors-and-modulenotfounderror-for-python

Answer 1

Dealing with "import" clauses, Python will first check if it is in its installation folder or whether it is installed package, if it fails, then it searches current working directory, with the relative path considered.

For example import tests.test_fibonacci means there is a folder called tests in your current working directory, and the script test_fibonacci.py is in it and python will run it from the first line to the last line in the namespace "tests.test_fibonacci".