format datetime.date objs appropriately for TSDB

Resolves #291

CHANGELOG.md

@@ -19,6 +19,8 @@
 
 * `delphin.tfs.FeatureStructure` raises a `TFSError` when attempting
   to assign a value on a non-subscriptable feature value ([#293])
+* `delphin.tsdb.format()` formats `datetime.date` objects in the TSDB
+  date format ([#291])
 
 
 ## [v1.2.4]
@@ -1384,5 +1386,6 @@ information about changes, except for
 [#285]: https://github.com/delph-in/pydelphin/issues/285
 [#288]: https://github.com/delph-in/pydelphin/issues/288
 [#289]: https://github.com/delph-in/pydelphin/issues/289
+[#291]: https://github.com/delph-in/pydelphin/issues/291
 [#293]: https://github.com/delph-in/pydelphin/issues/293
 [#296]: https://github.com/delph-in/pydelphin/issues/296

delphin/tsdb.py

@@ -14,7 +14,7 @@
 from gzip import open as gzopen
 import tempfile
 import shutil
-from datetime import datetime
+from datetime import datetime, date
 import warnings
 
 from delphin.exceptions import PyDelphinException, PyDelphinWarning
@@ -64,7 +64,7 @@
 
 RawValue = Union[str, None]
 RawRecord = Sequence[RawValue]
-Value = Union[str, int, float, datetime, None]
+Value = Union[str, int, float, datetime, date, None]
 Record = Sequence[Value]
 Records = Iterable[Record]
 ColumnMap = Dict[str, Value]  # e.g., a partial Record
@@ -680,10 +680,11 @@ def format(datatype: str,
         else:
             default = str(default)  # ensure it is a string
         raw_value = default
-    elif datatype == ':date' and isinstance(value, datetime):
+    elif datatype == ':date' and isinstance(value, (date, datetime)):
         month = _MONTHS[value.month]
         pattern = f'{value.day!s}-{month}-%Y'
-        if (value.hour, value.minute, value.second) != (0, 0, 0):
+        if (isinstance(value, datetime)
+                and (value.hour, value.minute, value.second) != (0, 0, 0)):
             pattern += ' %H:%M:%S'
         raw_value = value.strftime(pattern)
     else:

tests/tsdb_test.py

@@ -1,7 +1,7 @@
 
 import pathlib
 from collections import OrderedDict
-from datetime import datetime
+from datetime import datetime, date
 
 import pytest
 
@@ -217,6 +217,7 @@ def test_format():
     assert tsdb.format(':integer', None) == '-1'
     assert tsdb.format(':integer', None, default='1') == '1'
     assert tsdb.format(':date', datetime(1999, 9, 8)) == '8-sep-1999'
+    assert tsdb.format(':date', date(1999, 9, 8)) == '8-sep-1999'  # Issue #291
 
 
 def test_open(single_item_skeleton, gzipped_single_item_skeleton):