feat(lsp): add per-client commands (#16101)

3 files changed, 12 insertions, 5 deletions

diff --git a/runtime/lua/vim/lsp.lua b/runtime/lua/vim/lsp.lua
index a77dc8a13f..01e801415a 100644
--- a/runtime/lua/vim/lsp.lua
+++ b/runtime/lua/vim/lsp.lua
@@ -239,6 +239,7 @@ local function validate_client_config(config)
     on_exit         = { config.on_exit, "f", true };
     on_init         = { config.on_init, "f", true };
     settings        = { config.settings, "t", true };
+    commands        = { config.commands, 't', true };
     before_init     = { config.before_init, "f", true };
     offset_encoding = { config.offset_encoding, "s", true };
     flags           = { config.flags, "t", true };
@@ -590,6 +591,11 @@ end
 --- returned to the language server if requested via `workspace/configuration`.
 --- Keys are case-sensitive.
 ---
+---@param commands table Table that maps string of clientside commands to user-defined functions.
+--- Commands passed to start_client take precedence over the global command registry. Each key
+--- must be a unique comand name, and the value is a function which is called if any LSP action
+--- (code action, code lenses, ...) triggers the command.
+---
 ---@param init_options Values to pass in the initialization request
 --- as `initializationOptions`. See `initialize` in the LSP spec.
 ---
@@ -772,8 +778,9 @@ function lsp.start_client(config)
     attached_buffers = {};
 
     handlers = handlers;
-    requests = {};
+    commands = config.commands or {};
 
+    requests = {};
     -- for $/progress report
     messages = { name = name, messages = {}, progress = {}, status = {} };
   }
diff --git a/runtime/lua/vim/lsp/buf.lua b/runtime/lua/vim/lsp/buf.lua
index fdad9a91fc..6d85039958 100644
--- a/runtime/lua/vim/lsp/buf.lua
+++ b/runtime/lua/vim/lsp/buf.lua
@@ -480,7 +480,7 @@ local function on_code_action_results(results, ctx)
     end
     if action.command then
       local command = type(action.command) == 'table' and action.command or action
-      local fn = vim.lsp.commands[command.command]
+      local fn = client.commands[command.command] or vim.lsp.commands[command.command]
       if fn then
         local enriched_ctx = vim.deepcopy(ctx)
         enriched_ctx.client_id = client.id
diff --git a/runtime/lua/vim/lsp/codelens.lua b/runtime/lua/vim/lsp/codelens.lua
index 63fcbe430b..9eb64c9a2e 100644
--- a/runtime/lua/vim/lsp/codelens.lua
+++ b/runtime/lua/vim/lsp/codelens.lua
@@ -31,15 +31,15 @@ local function execute_lens(lens, bufnr, client_id)
   local line = lens.range.start.line
   api.nvim_buf_clear_namespace(bufnr, namespaces[client_id], line, line + 1)
 
+  local client = vim.lsp.get_client_by_id(client_id)
+  assert(client, 'Client is required to execute lens, client_id=' .. client_id)
   local command = lens.command
-  local fn = vim.lsp.commands[command.command]
+  local fn = client.commands[command.command] or vim.lsp.commands[command.command]
   if fn then
     fn(command, { bufnr = bufnr, client_id = client_id })
     return
   end
   -- Need to use the client that returned the lens → must not use buf_request
-  local client = vim.lsp.get_client_by_id(client_id)
-  assert(client, 'Client is required to execute lens, client_id=' .. client_id)
   local command_provider = client.server_capabilities.executeCommandProvider
   local commands = type(command_provider) == 'table' and command_provider.commands or {}
   if not vim.tbl_contains(commands, command.command) then