fix(lsp): check method is supported when range formatting (#21970)

`vim.lsp.buf.format()` silently did nothing if no servers supported
`textDocument/rangeFormatting` when formatting with a range.

Issue found by `@hwrd:matrix.org` in the Matrix chat.

1 files changed, 8 insertions, 8 deletions

diff --git a/runtime/lua/vim/lsp/buf.lua b/runtime/lua/vim/lsp/buf.lua
index be237eb494..6ac885c78f 100644
--- a/runtime/lua/vim/lsp/buf.lua
+++ b/runtime/lua/vim/lsp/buf.lua
@@ -197,20 +197,21 @@ function M.format(options)
     clients = vim.tbl_filter(options.filter, clients)
   end
 
+  local mode = api.nvim_get_mode().mode
+  local range = options.range
+  if not range and mode == 'v' or mode == 'V' then
+    range = range_from_selection()
+  end
+  local method = range and 'textDocument/rangeFormatting' or 'textDocument/formatting'
+
   clients = vim.tbl_filter(function(client)
-    return client.supports_method('textDocument/formatting')
+    return client.supports_method(method)
   end, clients)
 
   if #clients == 0 then
     vim.notify('[LSP] Format request failed, no matching language servers.')
   end
 
-  local mode = api.nvim_get_mode().mode
-  local range = options.range
-  if not range and mode == 'v' or mode == 'V' then
-    range = range_from_selection()
-  end
-
   ---@private
   local function set_range(client, params)
     if range then
@@ -221,7 +222,6 @@ function M.format(options)
     return params
   end
 
-  local method = range and 'textDocument/rangeFormatting' or 'textDocument/formatting'
   if options.async then
     local do_format
     do_format = function(idx, client)