diff --git a/tests/extmod/ure1.py b/tests/extmod/ure1.py
index aeadf4e5c..48537c2ea 100644
--- a/tests/extmod/ure1.py
+++ b/tests/extmod/ure1.py
@@ -11,6 +11,10 @@ try:
 except IndexError:
     print("IndexError")
 
+# conversion of re and match to string
+str(r)
+str(m)
+
 r = re.compile("(.+)1")
 m = r.match("xyz781")
 print(m.group(0))
diff --git a/tests/extmod/ure_split_notimpl.py b/tests/extmod/ure_split_notimpl.py
new file mode 100644
index 000000000..724e9d43b
--- /dev/null
+++ b/tests/extmod/ure_split_notimpl.py
@@ -0,0 +1,7 @@
+import ure as re
+
+r = re.compile('( )')
+try:
+    s = r.split("a b c foobar")
+except NotImplementedError:
+    print('NotImplementedError')
diff --git a/tests/extmod/ure_split_notimpl.py.exp b/tests/extmod/ure_split_notimpl.py.exp
new file mode 100644
index 000000000..437f61670
--- /dev/null
+++ b/tests/extmod/ure_split_notimpl.py.exp
@@ -0,0 +1 @@
+NotImplementedError