diff --git a/tests/test_number.py b/tests/test_number.py
index 5fb12fa6..4db0134d 100644
--- a/tests/test_number.py
+++ b/tests/test_number.py
@@ -83,6 +83,25 @@ def test_intcomma(
     assert humanize.intcomma(*test_args) == expected
 
 
+@pytest.mark.parametrize(
+    "thousands_sep, decimal_sep, expected",
+    [
+        (".", ",", "1.234.567,89"),
+        (" ", ",", "1 234 567,89"),
+    ],
+)
+def test_intcomma_localized_separators(
+    monkeypatch: pytest.MonkeyPatch,
+    thousands_sep: str,
+    decimal_sep: str,
+    expected: str,
+) -> None:
+    monkeypatch.setattr(number, "thousands_separator", lambda: thousands_sep)
+    monkeypatch.setattr(number, "decimal_separator", lambda: decimal_sep)
+
+    assert humanize.intcomma(1234567.89) == expected
+
+
 @pytest.mark.parametrize("sign", [1, -1])
 def test_intcomma_large_integer(sign: int) -> None:
     value = sign * (10**400 + 123)
@@ -297,6 +316,11 @@ def test_clamp(test_args: list[typing.Any], expected: str) -> None:
     assert humanize.clamp(*test_args) == expected
 
 
+def test_clamp_invalid_format() -> None:
+    with pytest.raises(ValueError, match="Invalid format"):
+        humanize.clamp(10, format=123)
+
+
 @pytest.mark.parametrize(
     "test_args, expected",
     [