Treesitter detach callback: Vim:Error executing lua callback: Vim:E315: ml_get: Invalid lnum: 1 about nvim-ts-rainbow2

[HiPhish]

@akinsho That branch does not really fix the problem, it just shoves it under the rug. There seems to be a resource leak which :Bdelete is tripping up on and I want to plug the leak. My last commit did plug a leak, but apparently it was not enough. I will have to install famiu/bufdelete.nvim myself and see what the command does.

[HiPhish]

I have pinned down the problem: In Neovim 0.10 deleting a buffer emits an on_changedtree event (see :h LanguageTree:register_cbs()), but since the buffer is deleted this raises all sort of problems. So the issue is not a resource leak after all. There are two possibilities:

1. This is a bug in Neovim
2. This is a deliberate choice in Neovim

If it is the former I can sit back and wait. If it is the latter I will have to handle this particular edge case like in the PR posted by the OP. I will file an issue in Neovim's repo, then we will see.

[HiPhish]

The on_detach callback is not documented (:h LanguageTree:register_cbs()). You do raise a good point though: if a buffer is deleted the current callbacks are never called, which is a resource leak. From reading the source it seems that on_detach is too radical, it will fire even if the user executes :edit. Perhaps a buffer_is_loaded() check at the beginning will do the trick.

[HiPhish]

@luozhiya Can you please try the on-detach branch and report back if the problem still happens?

[akinsho]

@HiPhish I've been experiencing this issue as well and tried your branch but it still happens on that branch. It does seem to be fixed on @luozhiya's branch though i.e. #42

[HiPhish]

I have been able to narrow down the issue. It only happens in the current dev builds, not in 0.9. If I have two windows with a different buffer for each and I execute :bdelete on one of them I get the error.

[HiPhish]

The PR has been merged. Please test if the problem has been solved on master and close this issue if everything is correct now.