Local modules can't be imported in napari-console

[psobolewskiPhD]

🐛 Bug

In contrast to the python REPL, ipython, VS Code, Jupyter, etc. the napari-console doesn't allow local modules/functions to be imported.
The sys.path in the napari-console does not include "" in sys.path, which is what permits searching of imports from the current dir.
See: https://docs.python.org/3/library/sys.html#sys.path

As a result launching napari from a dir does not permit easy importing of local modules.
Because of the inconsistency with other python tools and the fact that the console so strongly mimics those tools, I consider this a bug. (After some growing pains with the napari-console now I'm a big fan, especially for easy single-window hacking, as well as for demos/screensharing.)

However, as the discussion here on zulip with @Czaki points out, it could be considered a feature: https://napari.zulipchat.com/#narrow/stream/212875-general/topic/napari.20console.20vs.20ipython.3A.20importing.20local.20modules
By blocking local imports, the end user can't mask important "real" modules needed by plugins.

To Reproduce

Steps to reproduce the behavior:

1. Have a folder, e.g. dev or python_stuffs and a subfolder napari_scripts (or any other such)
2. Launch napari from terminal in dev or whatever.
3. Open console and try to import from a script/module in napari_scripts: from napari_scripts.napari_measure import measure_shape

Result:

ModuleNotFoundError: No module named 'napari_scripts'

The broader import from napari_scripts import napari_measure results in the same error, also it doesn't matter if the sub-dir napari_scripts has __init__.py or not.

(FYI if napari is launched directly from the subdirectory with the scripts, they still cannot be imported.)

Edit: to make matters more confusing for the end user, pwd() works correctly and shows the dir. Also, to further blur the lines between ipython and napari-console: they share a history.

Expected behavior

Both of the above imports work in any of the above mentioned python consoles (regardless of __init__.py). As a result, I would expect the import to work in napari-console and my local functions to be available.

Additional Context

The issue with possible local imports, as @Czaki pointed out is that a user with a local file like tensorflow.py will prevent a napari plugin that uses tensorflow from working.

I tested this by making such a file with just a test function that prints a string.
In live napari, stardist-napari (the tensorflow test plugin) works just fine.
If one uses:
import sys; sys.path.insert(0, "") to add "" to the top of sys.path my local imports work, but launching the Stardist plugin an error results, fairly clearly identifying the issue:

ImportError: cannot import name '__version__' from 'tensorflow' (/Users/piotrsobolewski/Dev/python_stuffs/tensorflow.py)

If one uses instead: import sys; sys.path.append('')
then again the local imports work, just like in ipython, et al (which have "" in sys.path at the bottom).
Importantly, Stardist plugin still works despite the "malicious/ignorant" tensorflow.py

So the key is to put "" after all the other search dirs (e.g. conda env ones).
ipython uses a init_path function that does this on start setting sys.path[0]=""

PS: Not sure if this should be here or napari-console repo?

Environment

napari: 0.4.16rc2.dev17+g0c148bb6
Platform: macOS-12.3.1-arm64-arm-64bit
System: MacOS 12.3.1
Python: 3.9.12 | packaged by conda-forge | (main, Mar 24 2022, 23:25:14) [Clang 12.0.1 ]
Qt: 5.15.2
PyQt5: 5.15.4
NumPy: 1.21.5
SciPy: 1.8.0
Dask: 2022.02.0
VisPy: 0.10.0

OpenGL:

• GL version: 2.1 Metal - 76.3
• MAX_TEXTURE_SIZE: 16384

Screens:

• screen 1: resolution 1680x1050, scale 2.0

Plugins:

• aicsimageio-in-memory: 0.6.1
• aicsimageio-out-of-memory: 0.6.1
• clEsperanto: 0.16.0
• console: 0.0.4
• napari-accelerated-pixel-and-object-classification: 0.6.8
• napari-assistant: 0.1.7
• napari-math: 0.0.1b0
• napari-ome-zarr: 0.4.0
• napari-sklearn-decomposition: 0.0.1
• napari-svg: 0.1.6
• napari-time-slicer: 0.4.3
• napari-tools-menu: 0.1.10
• napari_skimage_regionprops1: 0.4.0
• napari_skimage_regionprops2: 0.4.0
• natari: 0.2.7
• ome-types: 0.2.9
• scikit-image: 0.4.16rc2.dev17+g0c148bb6
• stardist-napari: 2022.4.8