fix(messages): no message kind for search pattern #31272

runtime/doc/ui.txt

@@ -800,6 +800,7 @@ must handle.
 		"rpc_error"	Error response from |rpcrequest()|
 		"return_prompt"	|press-enter| prompt after a multiple messages
 		"quickfix"	Quickfix navigation message
+		"search_cmd"	Entered search command
 		"search_count"	Search count message ("S" flag of 'shortmess')
 		"wmsg"		Warning ("search hit BOTTOM", |W10|, …)
 	    New kinds may be added in the future; clients should treat unknown

src/nvim/search.c

@@ -1203,6 +1203,7 @@ int do_search(oparg_T *oap, int dirc, int search_delim, char *pat, size_t patlen
 
       // Compute msg_row early.
       msg_start();
+      msg_ext_set_kind("search_cmd");
 
       // Get the offset, so we know how long it is.
       if (!cmd_silent

test/functional/ui/messages_spec.lua

@@ -1140,6 +1140,18 @@ stack traceback:
     exec_lua([[vim.print({ foo = "bar" })]])
     screen:expect_unchanged()
   end)
+
+  it('emits single message for normal search)', function()
+    feed('ax<cr>x<esc>?x<cr>')
+    screen:expect({
+      messages = {
+        {
+          content = { { '?x ' } },
+          kind = 'search_cmd',
+        },
+      },
+    })
+  end)
 end)
 
 describe('ui/builtin messages', function()