Improper handling of Unicode modifying diacritics

[stefanocoretta]

System details

RStudio Edition : Desktop
RStudio Version : 2022.12.0+353 (2022.12.0+353)
OS Version      : 13.1 (22C65)
R Version       : R version 4.2.2 (2022-10-31) -- "Innocent and Trusting"

Steps to reproduce the problem

1. Oper RStudio.
2. Create a new file (text or any other).
3. Write text with IPA diacritics. (Unicode IPA extensions and Combining diacritical marks).

Describe the problem in detail

The RStudio editor still does not correctly render combining diacritical marks like IPA diacritics, in that the text cursors is displaced one slot for each diacritic inserted and sometimes diacritics are not rendered correctly under the base character.

I had posted a question on the RStudio community forum a few years ago (I can't find it anymore) reporting the issue. It was said that this would be fixed when RStudio would switch to be built in Electron. I have not seen signs of this happening any time soon, or if it did, it did not fix the issue.

Describe the behavior you expected

• I have read the guide for submitting good bug reports.
• I have installed the latest version of RStudio, and confirmed that the issue still persists.
• If I am reporting an RStudio crash, I have included a diagnostics report.
• I have done my best to include a minimal, self-contained set of instructions for consistently reproducing the issue.

[ronblum]

@stefanocoretta Thank you for raising this! I'd like to reproduce the issue in my environment. What do you recommend as the best way to use IPA diacritics? I found a few methods for doing so, but I'd like to try and reproduce exactly the same steps.

[stefanocoretta]

Hi @ronblum :)

Can you perhaps just copy paste the following into a text file?

Phonetic transcription [ã̤n̺ ɾ̺ub̰ĩ̈] bla bla bla.

(Note that GH does not render the diacritics in the first character correctly, but copy pasting works correctly)

[ronblum]

From internal discussion: This might require updating the Ace editor.

[ronblum]

@stefanocoretta I tried a few other applications, spec. Notes and the Google Chrome address bar, and the diacritics seem to come out incorrectly, too, although in different ways. Can you check how they work?

[stefanocoretta]

I don't really expect them to work in anything that is not supposed to be an advanced text editor. :) It also depends on whether the typeface used supports those diacritics or not (of course I have been trying typefaces with the correct support when testing the RStudio editor).

[ronblum]

@stefanocoretta What font are you using? When I use Monaco and Menlo-regular, I get the expected result, but not with FiraCode-regular, which I'm guessing doesn't support combined diacritical marks.

[stefanocoretta]

It's Hasklug Nerd Font Mono, which renders all chars fine in other text editors. :)

[stefanocoretta]

Any success with this? I wonder if I should open an issue in the Ace editor repo, since it seems to be an issue with the editor rather than RStudio.