From a673c83198c87eb0a4b9bb3b0335a8fb4c835a93 Mon Sep 17 00:00:00 2001
From: Diomendius <42310725+Diomendius@users.noreply.github.com>
Date: Sat, 5 Oct 2024 22:38:52 +1300
Subject: [PATCH] fix: check buffer validity try_add()/try_add_wrapper()

Currently avoids an issue where a `FileType` autocommand schedules a
call to one of these functions but the buffer gets wiped out before the
next event loop. `nvim_get_option_value()` with the `filetype` argument
can cause this as it creates a transient buffer that only lasts for a
single function call.
---
 lua/lspconfig/manager.lua | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/lua/lspconfig/manager.lua b/lua/lspconfig/manager.lua
index 3457014854..51b145c636 100644
--- a/lua/lspconfig/manager.lua
+++ b/lua/lspconfig/manager.lua
@@ -244,6 +244,10 @@ end
 function M:try_add(bufnr, project_root)
   bufnr = bufnr or api.nvim_get_current_buf()
 
+  if not api.nvim_buf_is_valid(bufnr) then
+    return
+  end
+
   if vim.bo[bufnr].buftype == 'nofile' then
     return
   end
@@ -294,6 +298,10 @@ end
 --- @param bufnr integer
 --- @param project_root? string
 function M:try_add_wrapper(bufnr, project_root)
+  if not api.nvim_buf_is_valid(bufnr) then
+    return
+  end
+
   local config = self.config
   -- `config.filetypes = nil` means all filetypes are valid.
   if not config.filetypes or vim.tbl_contains(config.filetypes, vim.bo[bufnr].filetype) then