From 729e0acd269fad50bceb0381afffacc1468c2a61 Mon Sep 17 00:00:00 2001
From: Maria Solano <majosolano99@gmail.com>
Date: Sun, 5 Oct 2025 15:02:00 -0700
Subject: [PATCH] feat(lsp): pass client ID in code action filter (#36046)

---
 runtime/doc/lsp.txt         |  6 ++++--
 runtime/doc/news.txt        |  1 +
 runtime/lua/vim/lsp/buf.lua | 12 +++++++-----
 3 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/runtime/doc/lsp.txt b/runtime/doc/lsp.txt
index be6712ea62..eedc5ef567 100644
--- a/runtime/doc/lsp.txt
+++ b/runtime/doc/lsp.txt
@@ -1365,8 +1365,10 @@ code_action({opts})                                *vim.lsp.buf.code_action()*
                     values like `refactor` or `quickfix`.
                   • {triggerKind}? (`integer`) The reason why code actions
                     were requested.
-                • {filter}? (`fun(x: lsp.CodeAction|lsp.Command):boolean`)
-                  Predicate taking an `CodeAction` and returning a boolean.
+                • {filter}?
+                  (`fun(x: lsp.CodeAction|lsp.Command, client_id: integer):boolean`)
+                  Predicate taking a code action or command and the provider's
+                  ID. If it returns false, the action is filtered out.
                 • {apply}? (`boolean`) When set to `true`, and there is just
                   one remaining action (after filtering), the action is
                   applied without user query.
diff --git a/runtime/doc/news.txt b/runtime/doc/news.txt
index 234884b95c..e21ceaa949 100644
--- a/runtime/doc/news.txt
+++ b/runtime/doc/news.txt
@@ -252,6 +252,7 @@ LSP
   See |lsp-inline_completion| for quickstart instructions.
 • Support for `textDocument/onTypeFormatting`: |lsp-on_type_formatting|
   https://microsoft.github.io/language-server-protocol/specification/#textDocument_onTypeFormatting
+• The filter option of |vim.lsp.buf.code_action()| now receives the client ID as an argument.
 
 LUA
 
diff --git a/runtime/lua/vim/lsp/buf.lua b/runtime/lua/vim/lsp/buf.lua
index e520b7d7c1..61bbc99ccc 100644
--- a/runtime/lua/vim/lsp/buf.lua
+++ b/runtime/lua/vim/lsp/buf.lua
@@ -1117,8 +1117,9 @@ end
 ---   - {triggerKind}? (`integer`) The reason why code actions were requested.
 --- @field context? lsp.CodeActionContext
 ---
---- Predicate taking an `CodeAction` and returning a boolean.
---- @field filter? fun(x: lsp.CodeAction|lsp.Command):boolean
+--- Predicate taking a code action or command and the provider's ID.
+--- If it returns false, the action is filtered out.
+--- @field filter? fun(x: lsp.CodeAction|lsp.Command, client_id: integer):boolean
 ---
 --- When set to `true`, and there is just one remaining action
 --- (after filtering), the action is applied without user query.
@@ -1142,7 +1143,8 @@ end
 ---@param opts? vim.lsp.buf.code_action.Opts
 local function on_code_action_results(results, opts)
   ---@param a lsp.Command|lsp.CodeAction
-  local function action_filter(a)
+  ---@param client_id integer
+  local function action_filter(a, client_id)
     -- filter by specified action kind
     if opts and opts.context then
       if opts.context.only then
@@ -1168,7 +1170,7 @@ local function on_code_action_results(results, opts)
       end
     end
     -- filter by user function
-    if opts and opts.filter and not opts.filter(a) then
+    if opts and opts.filter and not opts.filter(a, client_id) then
       return false
     end
     -- no filter removed this action
@@ -1179,7 +1181,7 @@ local function on_code_action_results(results, opts)
   local actions = {}
   for _, result in pairs(results) do
     for _, action in pairs(result.result or {}) do
-      if action_filter(action) then
+      if action_filter(action, result.context.client_id) then
         table.insert(actions, { action = action, ctx = result.context })
       end
     end