tests/test_pyderasn.py | 37 +++++++++++++++++++++++++++++++++----

diff --git a/tests/test_pyderasn.py b/tests/test_pyderasn.py
index 29099b8584887b92b89c35472d27707be4b67b079609e4cc09b676d8fb1dd803..a6d61a6aa4ace7f582f5606afff631f6bc8faeb58f7a6682fa50ceb71645d4f8 100644
--- a/tests/test_pyderasn.py
+++ b/tests/test_pyderasn.py
@@ -3737,15 +3737,31 @@         repr(obj)
         list(obj.pps())
 
 
-class TestUTF8String(StringMixin, CommonMixin, TestCase):
-    base_klass = UTF8String
-
-
 cyrillic_letters = text(
     alphabet="".join(six_unichr(i) for i in list(range(0x0410, 0x044f + 1))),
     min_size=1,
     max_size=5,
 )
+
+
+class TestUTF8String(StringMixin, CommonMixin, TestCase):
+    base_klass = UTF8String
+
+    @given(cyrillic_letters)
+    def test_byte_per_primitive(self, chars):
+        char = chars[0]
+        char_raw = char.encode("utf-8")
+        encoded = b"".join((
+            self.base_klass().tag_constructed,
+            LENINDEF,
+            OctetString(char_raw[:1]).encode(),
+            OctetString(char_raw[1:2]).encode(),
+            EOC,
+        ))
+        self.assertEqual(
+            self.base_klass().decod(encoded, ctx={"bered": True}),
+            char,
+        )
 
 
 class UnicodeDecodeErrorMixin(object):
@@ -3785,6 +3801,19 @@             )
         repr(err.exception)
         self.assertEqual(err.exception.offset, offset)
         self.assertEqual(err.exception.decode_path, decode_path)
+
+    def test_byte_per_primitive(self):
+        encoded = b"".join((
+            self.base_klass().tag_constructed,
+            LENINDEF,
+            OctetString(b"1").encode(),
+            OctetString(b"2").encode(),
+            EOC,
+        ))
+        self.assertEqual(
+            self.base_klass().decod(encoded, ctx={"bered": True}),
+            "12",
+        )
 
 
 class TestPrintableString(