VSCode autocompletion doesn't "complete", duplicates existing text

Apologies if this is easily fixed, but I wasn’t able to find it in the docs.

On my Mac, when I type any VSCode autocompletion, the autocompletion appends to what I have already written, producing invalid code. Say I’m writing is.infinite, and I have written is., I navigate over to infinite and press tab or Enter and the editor produces is.is.infinite().

Is there a setting to change this behavior? Is this intended to be the default behavior? Or am I missing something?

Thank you.

[renkun-ken]

Ah! I just noticed that this issue only occurs inside .Rmd code chunks and not in .R files. Can you reproduce there?

Yes, I could reproduce it in rmd. Thanks for reporting!

[renkun-ken]

From the logging of the languageserver, the beginning tokens seem correct:

[2021-10-17 13:27:02.649] token: {
  "full_token": "is.",
  "right_token": "",
  "package": null,
  "accessor": "",
  "token": "is."
}

[2021-10-17 13:27:02.656] bracket is  

[2021-10-17 13:27:02.657] completions:  {
  "init_count": 57,
  "final_count": 57,
  "time": 0.0078,
  "isIncomplete": false
}

[2021-10-17 13:27:19.168] token: {
  "full_token": "data.",
  "right_token": "",
  "package": null,
  "accessor": "",
  "token": "data."
}

[2021-10-17 13:27:19.176] bracket is  

[2021-10-17 13:27:19.177] completions:  {
  "init_count": 62,
  "final_count": 62,
  "time": 0.0089,
  "isIncomplete": false
}