fix(lsp): fix multi client handling in code action (#18869)

Fixes https://github.com/neovim/neovim/issues/18860

(cherry picked from commit e4df1c9b9e)

runtime/lua/vim/lsp/buf.lua

@@ -516,7 +516,14 @@ local function on_code_action_results(results, ctx)
         enriched_ctx.client_id = client.id
         fn(command, enriched_ctx)
       else
-        M.execute_command(command)
+        -- Not using command directly to exclude extra properties,
+        -- see https://github.com/python-lsp/python-lsp-server/issues/146
+        local params = {
+          command = command.command,
+          arguments = command.arguments,
+          workDoneToken = command.workDoneToken,
+        }
+        client.request('workspace/executeCommand', params, nil, ctx.bufnr)
       end
     end
   end

test/functional/fixtures/fake-lsp-server.lua

@@ -673,6 +673,34 @@ function tests.code_action_with_resolve()
   }
 end
 
+function tests.code_action_server_side_command()
+  skeleton({
+    on_init = function()
+      return {
+        capabilities = {
+          codeActionProvider = {
+            resolveProvider = false,
+          },
+        },
+      }
+    end,
+    body = function()
+      notify('start')
+      local cmd = {
+        title = 'Command 1',
+        command = 'dummy1',
+      }
+      expect_request('textDocument/codeAction', function()
+        return nil, { cmd }
+      end)
+      expect_request('workspace/executeCommand', function()
+        return nil, cmd
+      end)
+      notify('shutdown')
+    end,
+  })
+end
+
 function tests.clientside_commands()
   skeleton {
     on_init = function()

test/functional/plugin/lsp_spec.lua

@@ -2665,6 +2665,45 @@ describe('LSP', function()
         end
       }
     end)
+    it('Calls workspace/executeCommand if no client side command', function()
+      local client
+      local expected_handlers = {
+        { NIL, {}, { method = 'shutdown', client_id = 1 } },
+        {
+          NIL,
+          { command = 'dummy1', title = 'Command 1' },
+          { bufnr = 1, method = 'workspace/executeCommand', client_id = 1 },
+        },
+        { NIL, {}, { method = 'start', client_id = 1 } },
+      }
+      test_rpc_server({
+        test_name = 'code_action_server_side_command',
+        on_init = function(client_)
+          client = client_
+        end,
+        on_setup = function() end,
+        on_exit = function(code, signal)
+          eq(0, code, 'exit code', fake_lsp_logfile)
+          eq(0, signal, 'exit signal', fake_lsp_logfile)
+        end,
+        on_handler = function(err, result, ctx)
+          ctx.params = nil -- don't compare in assert
+          eq(table.remove(expected_handlers), { err, result, ctx })
+          if ctx.method == 'start' then
+            exec_lua([[
+              local bufnr = vim.api.nvim_get_current_buf()
+              vim.lsp.buf_attach_client(bufnr, TEST_RPC_CLIENT_ID)
+              vim.fn.inputlist = function()
+                return 1
+              end
+              vim.lsp.buf.code_action()
+            ]])
+          elseif ctx.method == 'shutdown' then
+            client.stop()
+          end
+        end,
+      })
+    end)
   end)
   describe('vim.lsp.commands', function()
     it('Accepts only string keys', function()