hard to interpret error in Frame.show

[tlambert03]

Looks like Frame.show tries to infer the environment, but it looks like some of the assumptions/logic it's using is a bit faulty and can result in a NameError:

❯ python examples/desktop/line_collection/line_stack.py
/Users/talley/dev/forks/fastplotlib/fastplotlib/graphics/_features/_base.py:34: UserWarning: converting float64 array to float32
  warn(f"converting {array.dtype} array to float32")
Traceback (most recent call last):
  File "/Users/talley/dev/forks/fastplotlib/examples/desktop/line_collection/line_stack.py", line 27, in <module>
    plot.show(maintain_aspect=False)
  File "/Users/talley/dev/forks/fastplotlib/fastplotlib/layouts/_frame/_frame.py", line 170, in show
    self._output = QOutputContext(
                   ^^^^^^^^^^^^^^
NameError: name 'QOutputContext' is not defined

pip list

anyio                     4.1.0
appnope                   0.1.3
argon2-cffi               23.1.0
argon2-cffi-bindings      21.2.0
arrow                     1.3.0
asttokens                 2.4.1
async-lru                 2.0.4
attrs                     23.1.0
av                        11.0.0
Babel                     2.13.1
beautifulsoup4            4.12.2
black                     23.11.0
bleach                    6.1.0
build                     1.0.3
certifi                   2023.11.17
cffi                      1.16.0
cfgv                      3.4.0
charset-normalizer        3.3.2
check-manifest            0.49
click                     8.1.7
cmap                      0.1.3
comm                      0.2.0
contourpy                 1.2.0
cycler                    0.12.1
debugpy                   1.8.0
decorator                 5.1.1
defusedxml                0.7.1
distlib                   0.3.7
docutils                  0.20.1
executing                 2.0.1
fancycompleter            0.9.1
fastjsonschema            2.19.0
fastplotlib               0.1.0a16   /Users/talley/dev/forks/fastplotlib
filelock                  3.13.1
fonttools                 4.46.0
fqdn                      1.5.1
freetype-py               2.4.0
identify                  2.5.32
idna                      3.6
imageio                   2.33.0
importlib-metadata        6.10.0
iniconfig                 2.0.0
ipykernel                 6.27.1
ipython                   8.18.1
ipywidgets                8.1.1
isoduration               20.11.0
jaraco.classes            3.3.0
jedi                      0.19.1
Jinja2                    3.1.2
joblib                    1.3.2
json5                     0.9.14
jsonpointer               2.4
jsonschema                4.20.0
jsonschema-specifications 2023.11.2
jupyter_client            8.6.0
jupyter_core              5.5.0
jupyter-events            0.9.0
jupyter-lsp               2.2.1
jupyter-rfb               0.4.2
jupyter_server            2.11.1
jupyter_server_terminals  0.4.4
jupyterlab                4.0.9
jupyterlab_pygments       0.3.0
jupyterlab_server         2.25.2
jupyterlab-widgets        3.0.9
keyring                   24.3.0
kiwisolver                1.4.5
markdown-it-py            2.2.0
MarkupSafe                2.1.3
matplotlib                3.8.2
matplotlib-inline         0.1.6
mdurl                     0.1.2
mistune                   3.0.2
more-itertools            10.1.0
mypy                      1.7.1
mypy-extensions           1.0.0
nbclient                  0.6.8
nbconvert                 7.11.0
nbformat                  5.9.2
nbmake                    1.4.6
nest-asyncio              1.5.8
nh3                       0.2.14
nodeenv                   1.8.0
notebook_shim             0.2.3
numpy                     1.26.2
overrides                 7.4.0
packaging                 23.2
pandocfilters             1.5.0
parso                     0.8.3
pathspec                  0.11.2
pdbpp                     0.10.3
pexpect                   4.9.0
Pillow                    10.1.0
pip                       23.3.1
pkginfo                   1.9.6
platformdirs              4.0.0
pluggy                    1.3.0
pre-commit                3.5.0
prometheus-client         0.19.0
prompt-toolkit            3.0.41
psutil                    5.9.6
ptyprocess                0.7.0
pure-eval                 0.2.2
pycparser                 2.21
pygfx                     0.1.17
Pygments                  2.17.2
pylinalg                  0.4.1
pyparsing                 3.1.1
pyproject_hooks           1.0.0
pyrepl                    0.9.0
PySide6                   6.6.0
PySide6-Addons            6.6.0
PySide6-Essentials        6.6.0
pytest                    7.4.3
python-dateutil           2.8.2
python-json-logger        2.0.7
PyYAML                    6.0.1
pyzmq                     25.1.1
readme-renderer           42.0
referencing               0.31.1
requests                  2.31.0
requests-toolbelt         1.0.0
rfc3339-validator         0.1.4
rfc3986                   2.0.0
rfc3986-validator         0.1.1
rich                      13.3.1
rpds-py                   0.13.2
rubicon-objc              0.4.7
ruff                      0.1.6
scikit-learn              1.3.2
scipy                     1.11.4
Send2Trash                1.8.2
setuptools                68.2.2
shiboken6                 6.6.0
sidecar                   0.7.0
simplejpeg                1.7.2
six                       1.16.0
sniffio                   1.3.0
soupsieve                 2.5
stack-data                0.6.3
terminado                 0.18.0
threadpoolctl             3.2.0
tinycss2                  1.2.1
tornado                   6.4
tqdm                      4.66.1
traitlets                 5.14.0
twine                     4.0.2
types-python-dateutil     2.8.19.14
typing_extensions         4.8.0
uharfbuzz                 0.37.3
uri-template              1.3.0
urllib3                   2.1.0
virtualenv                20.25.0
wcwidth                   0.2.12
webcolors                 1.13
webencodings              0.5.1
websocket-client          1.7.0
wgpu                      0.13.0
wheel                     0.42.0
widgetsnbextension        4.0.9
wmctrl                    0.5
zipp                      3.17.0

I can probably figure out what is needed, but one way or another, the code probably shouldn't ever reach that NameError

[tlambert03]

(using pyqt6 instead of pyside6 solved it... but the error is still confusing)

[kushalkolar]

Sorry for the late reply, busy time of year! I think the issue is that you tried to force the Qt canvas but pyqt6 was not installed. Right now the %gui qt hook specifically looks for pyqt6, we have plans for pyside etc. support on the roadmap #384

[tlambert03]

What makes you say that? I use the %gui qt magic with pyside all the time.

I also could get this error simply by running the script outside of ipython.

But in any case, the issue here is not “add support for pyside”, it’s “ensure that a name error is never encountered, regardless of the user’s environment”

[kushalkolar]

Yup that hook works with pyside, but fastplotlib doesn't. This is one place where we need to add more than pyqt6: https://github.com/fastplotlib/fastplotlib/blob/main/fastplotlib%2Flayouts%2F_frame%2F_qt_output.py

[kushalkolar]

this was fixed in #431 , GUI selection mostly done by WGPU now