fix(lsp): use LspNotify for document_color (#40575)

fix(lsp): use LspNotify for document_color #40571

Problem: The document_color lsp module was already using the capability
framework but was still using raw buffer events to handle requests and
reloading. This means that every keystroke was sending a document_color
request to the server since there was no debounce in the raw handlers.

Solution: Switch to using LspNotify autocmd events. LspNotify fires just
after new document versions are synced with the server and provides a
built in debounce mechanism for changes. It also provides the signal for
when the current state should be cleared (didClose). The detach part is
already handled by the capability framework.

Fixes #39785

(cherry picked from commit 29db6ce84c)

runtime/lua/vim/lsp/document_color.lua

@@ -110,25 +110,22 @@ function Provider:new(bufnr)
   --- @type vim.lsp.document_color.Provider
   self = Capability.new(self, bufnr)
 
-  api.nvim_buf_attach(bufnr, false, {
-    on_lines = function(_, buf)
-      local provider = Provider.active[buf]
-      if not provider then
-        return true
+  api.nvim_create_autocmd('LspNotify', {
+    group = self.augroup,
+    buf = self.bufnr,
+    callback = function(ev)
+      local client_id = ev.data.client_id ---@type integer
+
+      if not self.client_state[client_id] then
+        return
       end
-      provider:request()
-    end,
-    on_reload = function(_, buf)
-      local provider = Provider.active[buf]
-      if provider then
-        provider:clear()
-        provider:request()
+
+      if ev.data.method == 'textDocument/didClose' then
+        self:clear(client_id)
       end
-    end,
-    on_detach = function(_, buf)
-      local provider = Provider.active[buf]
-      if provider then
-        provider:destroy()
+
+      if ev.data.method == 'textDocument/didChange' or ev.data.method == 'textDocument/didOpen' then
+        self:request(client_id)
       end
     end,
   })
@@ -138,10 +135,9 @@ function Provider:new(bufnr)
     desc = 'Refresh document_color',
     callback = function()
       color_cache = {}
-      local provider = Provider.active[bufnr]
-      if provider then
-        provider:clear()
-        provider:request()
+      for client_id, _ in pairs(self.client_state) do
+        self:clear(client_id)
+        self:request(client_id)
       end
     end,
   })
@@ -167,7 +163,6 @@ function Provider:on_detach(client_id)
     api.nvim_buf_clear_namespace(self.bufnr, state.namespace, 0, -1)
     self.client_state[client_id] = nil
   end
-  api.nvim__redraw({ buf = self.bufnr, valid = true, flush = false })
 end
 
 --- |lsp-handler| for the `textDocument/documentColor` method.
@@ -218,29 +213,29 @@ function Provider:handler(err, result, ctx)
 end
 
 --- @package
---- @param client_id? integer
+--- @param client_id integer
 function Provider:request(client_id)
-  for id in pairs(self.client_state) do
-    if not client_id or client_id == id then
-      local client = assert(lsp.get_client_by_id(id))
-      ---@type lsp.DocumentColorParams
-      local params = { textDocument = util.make_text_document_params(self.bufnr) }
-      client:request('textDocument/documentColor', params, function(...)
-        self:handler(...)
-      end, self.bufnr)
-    end
+  local state = self.client_state[client_id]
+  local client = assert(lsp.get_client_by_id(client_id))
+  if state and client then
+    ---@type lsp.DocumentColorParams
+    local params = { textDocument = util.make_text_document_params(self.bufnr) }
+    client:request('textDocument/documentColor', params, function(...)
+      self:handler(...)
+    end, self.bufnr)
   end
 end
 
 --- @package
-function Provider:clear()
-  for _, state in pairs(self.client_state) do
+--- @param client_id integer
+function Provider:clear(client_id)
+  local state = self.client_state[client_id]
+  if state then
     state.hl_info = {}
     state.processed_version = nil
     state.applied_version = nil
     api.nvim_buf_clear_namespace(self.bufnr, state.namespace, 0, -1)
   end
-  api.nvim__redraw({ buf = self.bufnr, valid = true, flush = false })
 end
 
 local document_color_ns = api.nvim_create_namespace('nvim.lsp.document_color')
@@ -406,8 +401,10 @@ function M.enable(enable, filter, opts)
     document_color_opts = vim.tbl_extend('keep', opts, document_color_opts)
     -- Re-process highlights with new style and refresh active providers.
     for _, provider in pairs(Provider.active) do
-      provider:clear()
-      provider:request()
+      for client_id, _ in pairs(provider.client_state) do
+        provider:clear(client_id)
+        provider:request(client_id)
+      end
     end
   end