diff --git a/tests/test-mdict.c b/tests/test-mdict.c
index 8eb9e9d3..f90bf0d8 100644
--- a/tests/test-mdict.c
+++ b/tests/test-mdict.c
@@ -419,6 +419,8 @@ static void test_init(void)
         string_printf(str1, "%d", 2*i);
         bool b = dict_str_erase (d1, str1);
         assert (b);
+        b = dict_str_erase (d1, str1);
+        assert (!b);
       }
       for(int i = 0; i < s; i++) {
         string_printf(str1, "%d", 2*i);
@@ -436,6 +438,16 @@ static void test_init(void)
         string_printf(str2, "%d", 2*i+1);
         dict_str_set_at (d1, str1, str2);
       }
+      for(int i = 1; i < s; i+=5) {
+        string_printf(str1, "%d", 2*i);
+        bool b = dict_str_erase (d1, str1);
+        assert (b);
+      }
+      for(int i = 1; i < s; i+=5) {
+        string_printf(str1, "%d", 2*i);
+        string_printf(str2, "%d", 2*i+1);
+        string_set( *dict_str_safe_get(d1, str1), str2);
+      }
       for(int i = 0; i < s; i++) {
         string_printf(str1, "%d", 2*i);
         bool b = dict_str_erase (d1, str1);