postwin: pcall nvim_win_close to ignore errors

[elgiano]

I've been in situation when the postwin is already closed and I get an error when trying to close it again, saying that it can't be closed. In this PR I wrap nvim_win_close in pcall, so that errors are ignored.

If anyone is curious about my actual use case, I have a function to move postwin from side to bottom:

local postwin = require 'scnvim.postwin'
local cfg = require 'scnvim.config'
cfg.postwin.horizontal = not cfg.postwin.horizontal
if postwin.is_open() then
    postwin.close()
end
postwin.open()

And this errors if the postwin is already closed.

[davidgranstrom]

Thanks for finding this. I'm wondering though if the actual bug is that postwin.is_open() answers true in this case when it shouldn't. Would be nice to see if that could be improved first - but otherwise this should do it.

[elgiano]

I agree, I'll stay a little longer without the fix and see if I find a way to reproduce. We are already checking for is_valid.. so I guess we are in a situation where window is valid but can't be closed... The only hint that comes to my mind is "textlock". Let's see if something comes up! Thanks

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-------- Original Message --------

On 10/3/25 10:20, David Granström wrote: davidgranstrom left a comment [(davidgranstrom/scnvim#260)](#260 (comment)) Thanks for finding this. I'm wondering though if the actual bug is that postwin.is_open() answers true in this case when it shouldn't. Would be nice to see if that could be improved first - but otherwise this should do it. — Reply to this email directly, [view it on GitHub](#260 (comment)), or [unsubscribe](https://github.com/notifications/unsubscribe-auth/AACNMWW4NPCQ7VMCY4UC3LL3VYWU7AVCNFSM6AAAAACIFBIR4KVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTGNRUG4ZTMOBYGU). You are receiving this because you authored the thread.Message ID: ***@***.***>

[davidgranstrom]

Using your code snippet an easy way to reproduce would be to:

1. Open a .scd file and start scnvim
2. :close the .scd buffer leaving only the post window visible
3. <C-o> to return to the .scd buffer
4. Run the code snippet (i.e. from a mapping) to trigger the error

[elgiano]

this worked perfectly, thanks!
So it's actually "E444: cannot close last window". How would you like to approach this? For my use case the pcall works, causing a second window to be open and to become the new postwin. Is it messy? Should we just let this error happen since it has a good reason?

[davidgranstrom]

Ideally postwin.is_open() should return false in this case. I haven't had a chance to look into the code yet, but I imagine this would be the proper fix instead of ignoring the error. If it proves too complicated I would consider merging this as a work around though.