bufadd does not sanitize windows drive letter capitalization

[mjlbach]

Neovim version (nvim -v)

NVIM v0.6.0-dev+463-g68b2a9e56

Vim (not Nvim) behaves the same?

N/A (pretty sure the pathing code diverged a long time ago)

Operating system/version

Widnows 10

Terminal name/version

Windows Termianal

$TERM environment variable

N/A

Installation

source build

How to reproduce the issue

file_location = os.getenv('TEMP')

local file_1 = file_location .. "\\file_1.txt"
local buffer_1 = vim.fn.bufadd(file_1)
print(vim.api.nvim_buf_get_name(buffer_1))

local drive_letter = string.sub(file_location, 1, 1)
local tail = string.sub(file_location, 2)
local perturbed_path = string.lower(drive_letter) .. tail
local file_2 = perturbed_path .. "\\file_2.txt"

local buffer_2 = vim.fn.bufadd(file_2)
print(vim.api.nvim_buf_get_name(buffer_2))

Expected behavior

vim.api.nvim_buf_get_name should show consistent capitalization for drive letters on windows regardless of the input to buf_add (which based on the code seems like it depends more on bufadd behavior than buf_get_name)

Actual behavior

C:\Users\michael\AppData\Local\Temp\file_1.txt
c:\Users\michael\AppData\Local\Temp\file_2.txt

[zeertzjq]

Does this bug also apply to Vim and Nvim's bufname()?

[mjlbach]

yes, the behavior depends on bufadd, not buf_get_name/bufname

[erw7]

I don't think this is a neovim (or vim) bug. If 'fileignorecase' is set properly, path_fnamecmp() will handle those differences properly. I think that is why bufadd does not do capitalization.

[mjlbach]

I guess the question is should it then. Currently when we want to compare on the lua side we have to sanitize the drive letter capitalization (which, to be fair, is trivial to do), because buf_get_name returns different values depending on the call to buff_add. I'm just not sure this behavior is intuitive

see:

• case sensitivity causes multiple servers running in the same directory nvim-lspconfig#1168

[hasansujon786]

I am having the same issue. Different results for different files.
-- c:\Users\hasan\dotfiles\nvim\lua\options.lua -- C:\Users\hasan\dotfiles\nvim\init.lua

[3N4N]

Was there any headway into fixing this? Does it even need fixing? As I see it, this shouldn't cause any problem. Sure, bufadd() doesn't capitalize drive letter, where is the problem in that? It's not like when you call buffadd() again with the same filename, but this time with different case of drive letter, it opens a new buffer. No, bufadd() behaves sensibly. It doesn't add a new buffer, even if the second call to buffadd() had a different case of drive letter.

Funny aside: command prompt doesn't sanitize drive letters either. If you do cd /d c:\, the prompt shows lowercase "c." If you do cd /d C:\, the prompt shows uppercase "C." No one cares.