1 files changed, 18 insertions, 0 deletions
diff --git a/tests/test_exception_custom_html.py b/tests/test_exception_custom_html.py
new file mode 100644
index 0000000..ec2f10b
--- /dev/null
+++ b/tests/test_exception_custom_html.py
@@ -0,0 +1,18 @@
+import pytest
+
+
+class CustomHtmlThatRaises:
+    def __html__(self):
+        raise ValueError(123)
+
+
+def test_exception_custom_html(escape):
+    """Checks whether exceptions in custom __html__ implementations are
+    propagated correctly.
+
+    There was a bug in the native implementation at some point:
+    https://github.com/pallets/markupsafe/issues/108
+    """
+    obj = CustomHtmlThatRaises()
+    with pytest.raises(ValueError):
+        escape(obj)