coverage increase: test for graceful failing on read callback wrong return type

hoefling · hoefling · commit fc565ba2b824 · 2021-09-05T18:20:13.000+02:00
Signed-off-by: Oleg Hoefling &lt;oleg.hoefling@gmail.com&gt;
diff --git a/tests/test_main.py b/tests/test_main.py
@@ -156,3 +156,12 @@ def test_register_non_callables(self):
             cbs = self._mismatch_callbacks()
             cbs[idx] = None
             self.assertRaises(TypeError, xmlsec.register_callbacks, *cbs)
+
+    def test_sign_external_data_fails_on_read_callback_wrong_returns(self):
+        xmlsec.register_callbacks(
+            lambda filename: filename == b'cid:123456',
+            lambda filename: BytesIO(b'<html><head/><body/></html>'),
+            lambda bio, buf: None,
+            lambda bio: bio.close(),
+        )
+        self._expect_sign_failure()
