ported the full output optimization code from VSCode

[jonah-iden]

What it does

Fixes #13069
Fixes #13152
this ports all the ouput optimization vscode is doing over to theia.

How to test

See linked Task for specific test case.
Open or create a notebook and execute a cell with stdout output

Follow-ups

Review checklist

• As an author, I have thoroughly tested my changes and carefully followed the review guidelines
• IP Check Ticket

Reminder for reviewers

• As a reviewer, I agree to behave in accordance with the review guidelines

[msujew]

@JonasHelming Is there a specific commit we are allowed to use from vscode, so we don't have to create an IP check ticket? I remember I heard something about that in one of the dev calls.

[jonah-iden]

Btw could any of you test this. It seems like there is still an issue because i somtimes get no stdout ouput at all.
im not able to start theia with python and jupyther installed right now. No idea why it seems its crashing when [ms-python.vscode-pylance]: trying to resolve latest version but im not getting any errors even when i put that code in a try catch

[bvenreply]

Hello @jonah-iden, I tested the PR on the minimal example I gave in the issue and now the output matches what is expected.

I also checked the original usecase that prompted the creation of the issue in the first place; Unfortunately, there's still a problem there:

I noticed that somehow, if both stdout and stderr streams are used in the output, the characters are no longer correctly erased. This does not occur in vscode.

You should be able to reproduce this with a small change to the Python code I provided in the issue:

import time
import sys

msg = "abcdef"
print("spoiler!", flush=True, file=sys.stderr)

for i in range(5):
    print(msg, end="", flush=True)
    time.sleep(1)
    for j in msg:
        print("\b", end="", flush=True)
    time.sleep(0.5)

This does not look strictly related to #13069 so if you feel I should open another issue let me know.

[jonah-iden]

@bvenreply I'll take a look today and if i can't find problem quickly lets create a new Issue for that

[jonah-iden]

Ok after a first look this new problem seems to be a larger issue inside the ouput update logic. I think we should create a separate issue for it. Maybe i can find some time on friday to take a deeper look

[bvenreply]

Ok after a first look this new problem seems to be a larger issue inside the ouput update logic. I think we should create a separate issue for it. Maybe i can find some time on friday to take a deeper look

Got it. I will open it myself later today.

[msujew]

Thanks, looks good to me 👍

I can confirm that both issues are fixed with this change.

[JonasHelming]

@bvenreply Could you confirm it works for you, please?

[jonah-iden]

@JonasHelming was allready confirmed on the issue #13152 (comment)

[JonasHelming]

@JonasHelming was allready confirmed on the issue #13152 (comment)

perfect thank you, I missed that. Thanks for solving this so quickly and thanks for the original report and restesting!