Catch for non-digit values and add unit test

synapseclient/core/utils.py

@@ -274,7 +274,12 @@ def validate_submission_id(
         if syn_id is not None:
             return validate_submission_id(syn_id)
     else:
-        int_submission_id = int(float(submission_id))
+        try:
+            int_submission_id = int(float(submission_id))
+        except ValueError:
+            raise ValueError(
+                f"Submission ID '{submission_id}' is not a valid submission ID. Please use digits only."
+            )
         LOGGER.warning(
             f"Submission ID '{submission_id}' contains decimals which are not supported. "
             f"Submission ID will be converted to '{int_submission_id}'."

tests/unit/synapseclient/core/unit_test_utils.py

@@ -135,6 +135,15 @@ def test_validate_submission_id(input_value, expected_output, expected_warning,
             assert not caplog.text
 
 
+def test_validate_submission_id_letters_input() -> None:
+    letters_input = "syn123"
+    expected_error = f"Submission ID '{letters_input}' is not a valid submission ID. Please use digits only."
+    with pytest.raises(ValueError) as err:
+        utils.validate_submission_id(letters_input)
+
+    assert str(err.value) == expected_error
+
+
 # TODO: Add a test for is_synapse_id_str(...)
 # https://sagebionetworks.jira.com/browse/SYNPY-1425