fix(lsp): avoid indexing vim.NIL for null workspaceFolders (#16404)

* internally represent no workspaceFolders as nil instead of vim.NIL
* rename workspaceFolders -> workspace_folders for consistency

1 files changed, 7 insertions, 7 deletions

diff --git a/runtime/lua/vim/lsp/buf.lua b/runtime/lua/vim/lsp/buf.lua
index 747d761730..d3ba766d89 100644
--- a/runtime/lua/vim/lsp/buf.lua
+++ b/runtime/lua/vim/lsp/buf.lua
@@ -369,7 +369,7 @@ end
 function M.list_workspace_folders()
   local workspace_folders = {}
   for _, client in pairs(vim.lsp.buf_get_clients()) do
-    for _, folder in pairs(client.workspaceFolders or {}) do
+    for _, folder in pairs(client.workspace_folders or {}) do
       table.insert(workspace_folders, folder.name)
     end
   end
@@ -389,7 +389,7 @@ function M.add_workspace_folder(workspace_folder)
   local params = util.make_workspace_params({{uri = vim.uri_from_fname(workspace_folder); name = workspace_folder}}, {{}})
   for _, client in pairs(vim.lsp.buf_get_clients()) do
     local found = false
-    for _, folder in pairs(client.workspaceFolders or {}) do
+    for _, folder in pairs(client.workspace_folders or {}) do
       if folder.name == workspace_folder then
         found = true
         print(workspace_folder, "is already part of this workspace")
@@ -398,10 +398,10 @@ function M.add_workspace_folder(workspace_folder)
     end
     if not found then
       vim.lsp.buf_notify(0, 'workspace/didChangeWorkspaceFolders', params)
-      if not client.workspaceFolders then
-        client.workspaceFolders = {}
+      if not client.workspace_folders then
+        client.workspace_folders = {}
       end
-      table.insert(client.workspaceFolders, params.event.added[1])
+      table.insert(client.workspace_folders, params.event.added[1])
     end
   end
 end
@@ -415,10 +415,10 @@ function M.remove_workspace_folder(workspace_folder)
   if not (workspace_folder and #workspace_folder > 0) then return end
   local params = util.make_workspace_params({{}}, {{uri = vim.uri_from_fname(workspace_folder); name = workspace_folder}})
   for _, client in pairs(vim.lsp.buf_get_clients()) do
-    for idx, folder in pairs(client.workspaceFolders) do
+    for idx, folder in pairs(client.workspace_folders) do
       if folder.name == workspace_folder then
         vim.lsp.buf_notify(0, 'workspace/didChangeWorkspaceFolders', params)
-        client.workspaceFolders[idx] = nil
+        client.workspace_folders[idx] = nil
         return
       end
     end