diff --git a/pyproject.toml b/pyproject.toml
index 5dc6740..9e24e81 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -15,6 +15,7 @@ exclude_lines = [
     'pragma: no cover',
     'raise NotImplementedError',
     'if __name__ == .__main__.:',
+    '\.\.\.',
 ]
 ignore_errors = true
 omit = ['docs/*', 'tests/*']
diff --git a/tests/signing/tests.py b/tests/signing/tests.py
index 72cd787..e2aa3b1 100644
--- a/tests/signing/tests.py
+++ b/tests/signing/tests.py
@@ -113,6 +113,7 @@ def test_sign_unsign_object(self):
             ["a", "list"],
             "a string \u2019",
             {"a": "dictionary"},
+            "a" * 100,
         ]
         for obj in tests:
             with self.subTest(obj=obj):
@@ -310,6 +311,10 @@ def test_works_with_non_ascii_keys(self):
             s.sign("foo"),
         )
 
+    def test_unsupported_algorithm(self):
+        with self.assertRaises(InvalidAlgorithm):
+            signing.BytesSigner("predictable-key", algorithm="whatever")
+
 
 class TestFernetSigner(SimpleTestCase):
     def test_fernet_signer(self):
@@ -344,9 +349,10 @@ def test_bad_payload(self):
             # Break the signature
             signer.unsign(value[:-1] + b" ")
 
-    def test_unsupported(self):
-        value = b"hello"
-        signer = signing.FernetSigner("predictable-key")
-
         with self.assertRaises(signing.BadSignature):
-            signer.unsign(value)
+            # Break everything
+            signer.unsign(b"hello")
+
+    def test_unsupported_algorithm(self):
+        with self.assertRaises(InvalidAlgorithm):
+            signing.FernetSigner("predictable-key", algorithm="whatever")