patch 9.0.1989: Vim9: double error message given

Problem:  Vim9: double error message given
Solution: Only give second error message, if ther
          wasn't one given before

closes: #13278

Signed-off-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: Ernie Rael <errael@raelity.com>
diff --git a/src/version.c b/src/version.c
index 02dd9bf..64c68d9 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1989,
+/**/
     1988,
 /**/
     1987,
diff --git a/src/vim9class.c b/src/vim9class.c
index 925149e..295716e 100644
--- a/src/vim9class.c
+++ b/src/vim9class.c
@@ -2221,6 +2221,7 @@
 	return FAIL;
     size_t len = name_end - name;
 
+    int did_emsg_save = did_emsg;
     class_T *cl;
     if (rettv->v_type == VAR_CLASS)
 	cl = rettv->vval.v_class;
@@ -2310,7 +2311,8 @@
 	    return OK;
 	}
 
-	member_not_found_msg(cl, VAR_OBJECT, name, len);
+	if (did_emsg == did_emsg_save)
+	    member_not_found_msg(cl, VAR_OBJECT, name, len);
     }
 
     else if (rettv->v_type == VAR_CLASS)