Fix: Use midnight UTC for date-only CLI timestamps instead of current time (#220)

Author: Marenz

RELEASE_NOTES.md

@@ -15,6 +15,7 @@
   - `filter_queries` parameter supports text-based filtering on dispatch `id` and `type` fields
       - Query format: IDs are prefixed with `#` (e.g., `#4`), types are matched as substrings (e.g., `bar` matches `foobar`)
       - Multiple queries are combined with logical OR
+* Date-only inputs in CLI timestamps now default to midnight UTC instead of using the current time.
 
 ## Bug Fixes
 

src/frequenz/client/dispatch/_cli_types.py

@@ -57,6 +57,15 @@ def convert(
             if parse_status == 0:
                 self.fail(f"Invalid time expression: {value}", param, ctx)
 
+            # Check if only a date was provided (no time component)
+            # parsedatetime returns status 1 for date-only parsing
+            if parse_status == 1:
+                # Set time to midnight in UTC for date-only inputs
+                # First convert to UTC, then set time to midnight
+                parsed_dt = parsed_dt.astimezone(timezone.utc).replace(
+                    hour=0, minute=0, second=0, microsecond=0
+                )
+
             return cast(datetime, parsed_dt.astimezone(timezone.utc))
         except Exception as e:  # pylint: disable=broad-except
             self.fail(

tests/test_cli.py

@@ -17,6 +17,7 @@
     ElectricalComponentCategory,
 )
 from frequenz.client.dispatch.__main__ import cli
+from frequenz.client.dispatch._cli_types import FuzzyDateTime
 from frequenz.client.dispatch.recurrence import (
     EndCriteria,
     Frequency,
@@ -739,3 +740,30 @@ async def test_delete_command(
     assert expected_output in result.output
     if dispatches:
         assert len(fake_client.dispatches(MicrogridId(1))) == 0
+
+
+def test_fuzzy_datetime_date_only() -> None:
+    """Test that date-only inputs are parsed as midnight."""
+    fuzzy_dt = FuzzyDateTime()
+
+    # Test date-only input
+    result = fuzzy_dt.convert("2025-08-06", None, None)
+    assert isinstance(result, datetime)
+    # Check that time is set to midnight in UTC (accounting for timezone conversion)
+    # For Europe/Berlin (UTC+2), midnight local time becomes 22:00 UTC previous day
+    assert result.hour in [
+        0,
+        22,
+    ]  # Could be 0 (UTC) or 22 (UTC for Europe/Berlin midnight)
+    assert result.minute == 0
+    assert result.second == 0
+    assert result.microsecond == 0
+
+    # Test date-time input (should preserve time)
+    result_with_time = fuzzy_dt.convert("2025-08-06 14:30:15", None, None)
+    assert isinstance(result_with_time, datetime)
+    # Time should be preserved (accounting for timezone conversion)
+    # For Europe/Berlin (UTC+2), 14:30 local becomes 12:30 UTC
+    assert result_with_time.hour in [12, 14]  # Could be 12 (UTC) or 14 (local)
+    assert result_with_time.minute == 30
+    assert result_with_time.second == 15