Slow time to display completions

[alandema]

Problem Description

The completion and snippets are much slower than in other IDEs. Something similar was described in #15042 which is now closed, but I don't feel comfortable with the actual completion in Spyder. This is not a new issue, but only now trying other IDEs I have noticed how slow is the completion in Spyder.

I know this GIFs are not a proof because I can type different anytime, but they meant to demonstrate the almost instantly completion and snippets options showing along with your typing in VSCode and how reliable they are. In Spyder they have a 0.5s to 1s delay to display. The fact is: you have to stop your writing to wait for completion suggestions.

In both cases I was using Kite.

VSCode

Spyder. Sometimes I also need to navigate to second or third option, even if what I typed has no relation to the first option.

What steps reproduce the problem?

1. Write some code

What is the expected output? What do you see instead?

I would expect to get a fast completion as in other IDEs like VSCode or PyCharm.

Versions

• Spyder version: 5.1.2 None
• Python version: 3.9.5 64-bit
• Qt version: 5.12.10
• PyQt5 version: 5.12.3
• Operating System: Windows 10

Dependencies

Mandatory:

atomicwrites >=1.2.0 : 1.4.0 (OK)
chardet >=2.0.0 : 4.0.0 (OK)
cloudpickle >=0.5.0 : 1.6.0 (OK)
cookiecutter >=1.6.0 : 1.7.3 (OK)
diff_match_patch >=20181111 : 20200713 (OK)
intervaltree >=3.0.2 : 3.1.0 (OK)
IPython >=7.6.0 : 7.27.0 (OK)
jedi >=0.17.2;<0.19.0 : 0.18.0 (OK)
jsonschema >=3.2.0 : 3.2.0 (OK)
keyring >=17.0.0 : 23.1.0 (OK)
nbconvert >=4.0 : 6.1.0 (OK)
numpydoc >=0.6.0 : 1.1.0 (OK)
paramiko >=2.4.0 : 2.7.2 (OK)
parso >=0.7.0;<0.9.0 : 0.8.2 (OK)
pexpect >=4.4.0 : 4.8.0 (OK)
pickleshare >=0.4 : 0.7.5 (OK)
psutil >=5.3 : 5.8.0 (OK)
pygments >=2.0 : 2.10.0 (OK)
pylint >=2.5.0;<2.10.0 : 2.9.6 (OK)
pyls_spyder >=0.4.0 : 0.4.0 (OK)
pylsp >=1.2.2;<1.3.0 : 1.2.2 (OK)
pylsp_black >=1.0.0 : None (OK)
qdarkstyle =3.0.2 : 3.0.2 (OK)
qstylizer >=0.1.10 : 0.2.1 (OK)
qtawesome >=1.0.2 : 1.0.3 (OK)
qtconsole >=5.1.0 : 5.1.1 (OK)
qtpy >=1.5.0 : 1.10.0 (OK)
rtree >=0.9.7 : 0.9.7 (OK)
setuptools >=49.6.0 : 52.0.0.post20210125 (OK)
sphinx >=0.6.6 : 4.1.2 (OK)
spyder_kernels >=2.1.1;<2.2.0 : 2.1.1 (OK)
textdistance >=4.2.0 : 4.2.1 (OK)
three_merge >=0.1.1 : 0.1.1 (OK)
watchdog >=0.10.3 : 2.1.5 (OK)
zmq >=17 : 22.2.1 (OK)

Optional:

cython >=0.21 : None (OK)
matplotlib >=2.0.0 : 3.4.3 (OK)
numpy >=1.7 : 1.21.2 (OK)
pandas >=1.1.1 : 1.3.2 (OK)
scipy >=0.17.0 : 1.7.1 (OK)
sympy >=0.7.3 : None (OK)

[ccordoba12]

Hey @alandema, thanks for reporting. After thinking about this problem for some days, I noticed that during the migration to the new API we have in Spyder 5, we lost an important configurable option that we exposed in Spyder 4: Show automatic completions after keyboard idle.

That option tells Spyder to wait for a bit (300 milliseconds by default) before requesting and showing completions. We do this for two reasons:

• We prefer not to clutter the code editing experience by showing a changing list a lot of completion results while typing.
• We also don't want to send too many requests to the server in charge of completions to not cause possible deadlocks on it.

However, by exposing that option again (which I plan to do in our 5.2.0 version), setting its value to 0, and setting the other options shown below

(for now it's necessary to disable completion snippets, we'll see if we can avoid that in 5.2.0), you'll get a much closer experience to what you see in VSCode/Pycharm:

[alandema]

Indeed, I missed the latency option in 5.1.2 when I searched for it. Glad to know that we will get a similar experience to VSCode/PyCharm about this feature. At least for me, this helps me a lot to code faster without typos.

[isabela-pf]

We talked about this in a meeting today, and since it seems like there's not a technical blocker I agree it's better to meet user expectations where we can.

This includes removing the delay as default and providing configuration in preferences.