[bug fix] Fix the flickering terminal widget when resizing.

[meng-jpg]

What it does

Call debounce for the method resizeTerminal to fix the issue of widget content flickering when the terminal widget is resizing.
Issue: #12280

How to test

1.start theia electron
2.open a new terminal
3.resize the window

Review checklist

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

Reminder for reviewers

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

[msujew]

Thank you for your first contribution 👍

[tsmaeder]

@msujew @vince-fugnitto this looks like a low-hanging fruit for getting our PR count down :-)

[vince-fugnitto]

@meng-jpg just so you're aware, it has been difficult to merge the pull-request due to a CI option we have where the branch needs to be constantly rebased to master and not out-of-date. Unfortunately we cannot perform the update ourselves unless you grant committers access to perform edits.

[meng-jpg]

@meng-jpg just so you're aware, it has been difficult to merge the pull-request due to a CI option we have where the branch needs to be constantly rebased to master and not out-of-date. Unfortunately we cannot perform the update ourselves unless you grant committers access to perform edits.

Sorry, the PR was created from a fork living under an organization (rather than an individual). I cannot find the Allow edits from maintainers button.
https://github.com/orgs/community/discussions/5634

[vince-fugnitto]

LGTM 👍 I confirmed that the resizing behavior is much better after the updates.

---

The only impediment is the "out-of-date" check which I (or other committers) unfortunately cannot update the pull-request for you.

[msujew]

@meng-jpg Sorry, do you mind rebasing again? Someone else merged their PR before we could merge yours.

[msujew]

During automated tests, this proposeDimensions function call yields undefined for some reason, which makes our tests fail. I'm not sure why, since it really shouldnt. However, we should just guard against it to fix the tests. See also here

[marcdumais-work]

I believe we have a race condition. The previous test creates a terminal widget and it's then disposed it in the afterEach() before the following (failing) test is run. What I think happens is that between the moment the resize is triggered and the debounce delay has expired, the previous test is finished, and the terminal widget has been disposed.

It's not something likely to happen at the human scale, but since we introduce a delay here, it seems reasonable to make sure that the widget is not disposed before trying to access its internals. e.g.:

protected doResizeTerminal(): void {
   if (this.isDisposed) {
      return;
   }
   const geo = this.fitAddon.proposeDimensions();
[...]

[msujew]

@meng-jpg Do you mind addressing the issue that I outlined here? It makes our test suite fail.

[meng-jpg]

@meng-jpg Do you mind addressing the issue that I outlined here? It makes our test suite fail.

I will try, but this issue seems a bit strange, I don't know if I can resolve it.

[marcdumais-work]

I will try, but this issue seems a bit strange, I don't know if I can resolve it.

@meng-jpg Please see my comment above - i think it will be easily fixed. Let us know if you need help with anything.

[vince-fugnitto]

@meng-jpg are you still interested in contributing the pull-request, for the failing test please see #12320 (comment).

The current state breaks our integration test suite.

[msujew]

I have created #12587 to fix this issue, since the original contributor doesn't answer.