more tests

Signed-off-by: Sreekanth <prsreekanth920@gmail.com>

Author: BulkBeing

packages/pynumaflow/tests/test_validate.py

@@ -0,0 +1,31 @@
+import pytest
+
+from pynumaflow._validate import _validate_message_fields
+
+
+class TestValidateMessageFields:
+    def test_invalid_value_type_raises(self):
+        with pytest.raises(TypeError, match="Message 'value' must be bytes, got str"):
+            _validate_message_fields("not bytes", None, None)
+
+    def test_invalid_keys_type_raises(self):
+        with pytest.raises(TypeError, match="Message 'keys' must be a list of strings"):
+            _validate_message_fields(None, "not-a-list", None)
+
+    def test_invalid_keys_element_type_raises(self):
+        with pytest.raises(TypeError, match="Message 'keys' must be a list of strings"):
+            _validate_message_fields(None, [1, 2], None)
+
+    def test_invalid_tags_type_raises(self):
+        with pytest.raises(TypeError, match="Message 'tags' must be a list of strings"):
+            _validate_message_fields(None, None, "not-a-list")
+
+    def test_invalid_tags_element_type_raises(self):
+        with pytest.raises(TypeError, match="Message 'tags' must be a list of strings"):
+            _validate_message_fields(None, None, [1, 2])
+
+    def test_valid_inputs_no_error(self):
+        _validate_message_fields(b"data", ["key1"], ["tag1"])
+
+    def test_all_none_no_error(self):
+        _validate_message_fields(None, None, None)