[WIP] Keep content assist popup open even if user input has no matches

[trancexpress]

WIP, DONT MERGE

Fixes: #2260

[trancexpress]

There are artifacts with the current change, will have to look into those when I find time:

gh2260_content_assist_artifacts.webm

Opened https://github.com/eclipse-jdt/eclipse.jdt.ui/issues/1643 for this.

[github-actions[bot]]

Test Results

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Results for commit 6600fb81. ± Comparison against base commit adbbaa63.

[mickaelistria]

The proposal seems like a clear enhancement to me. I would enjoy the IDE providing this. One thing I believe is important is that if user closes the popup (hits Escape), the popup doesn't show again except if it has actual proposals.

[trancexpress]

One thing I believe is important is that if user closes the popup (hits Escape), the popup doesn't show again except if it has actual proposals.

To be clear, https://github.com/eclipse-platform/eclipse.platform.ui/issues/2260 is for keeping the content assist popup once opened with the usual invocation. We don't aim for https://github.com/eclipse-platform/eclipse.platform.ui/issues/888, i.e. open the content assist popup automatically as soon as there is a proposal.

So we don't change how the popup is shown, we only keep it open once shown.

Though maybe I misunderstand your concern? Is there some preference that lets content assist show up automatically on typing, that I must test with?