Reject ISO durations with empty time sections

rust/src/parsing.rs

@@ -597,6 +597,7 @@ impl<'a> Parser<'a> {
 
         let mut duration: ParsedDuration = ParsedDuration::new();
         let mut got_t: bool = false;
+        let mut has_time_component = false;
         let mut last_had_fraction = false;
 
         loop {
@@ -683,6 +684,7 @@ impl<'a> Parser<'a> {
                                 )
                             }
                         }
+                        has_time_component = true;
                     } else {
                         match self.current {
                             'Y' => {
@@ -791,6 +793,10 @@ impl<'a> Parser<'a> {
             }
         }
 
+        if got_t && !has_time_component {
+            return Err(self.parse_error("Missing time component in duration".to_string()));
+        }
+
         parsed.duration = Some(duration);
 
         Ok(())

src/pendulum/parsing/iso8601.py

@@ -268,6 +268,11 @@ def _parse_iso8601_duration(text: str, **options: str) -> Duration | None:
     if not m or (not m.group("w") and not m.group("ymd") and not m.group("hms")):
         return None
 
+    if m.group("timesep") and not any(
+        m.group(unit) for unit in ("hours", "minutes", "seconds")
+    ):
+        return None
+
     years = 0
     months = 0
     weeks = 0

tests/parsing/test_parse_iso8601.py

@@ -191,6 +191,14 @@ def test_parse_iso8601_invalid():
         ("PT1.5H", (0, 0, 0, 0, 1, 30, 0, 0)),
         ("PT1,5H", (0, 0, 0, 0, 1, 30, 0, 0)),
         ("P2Y30M4DT5H6M7S", (2, 30, 0, 4, 5, 6, 7, 0)),
+        ("PT0H", (0, 0, 0, 0, 0, 0, 0, 0)),
+        ("PT0M", (0, 0, 0, 0, 0, 0, 0, 0)),
+        ("PT0S", (0, 0, 0, 0, 0, 0, 0, 0)),
+        ("PT0.0S", (0, 0, 0, 0, 0, 0, 0, 0)),
+        ("P0D", (0, 0, 0, 0, 0, 0, 0, 0)),
+        ("P1DT0S", (0, 0, 0, 1, 0, 0, 0, 0)),
+        ("P1Y2MT0H", (1, 2, 0, 0, 0, 0, 0, 0)),
+        ("P1DT2S", (0, 0, 0, 1, 0, 0, 2, 0)),
     ],
 )
 def test_parse_iso8601_duration(
@@ -210,7 +218,8 @@ def test_parse_iso8601_duration(
     ) == expected
 
 
-def test_parse_iso8601_duration_invalid():
-    # Must include at least one element
+@pytest.mark.parametrize("text", ["P", "PT", "P1DT", "P0DT", "P1Y2MT", "P1.5DT"])
+def test_parse_iso8601_duration_invalid(text: str) -> None:
+    # Durations need a component, and T must be followed by a time component.
     with pytest.raises(ValueError):
-        parse_iso8601("P")
+        parse_iso8601(text)

tests/test_parsing.py

@@ -1,7 +1,10 @@
 from __future__ import annotations
 
+import pytest
+
 import pendulum
 
+from pendulum.parsing import ParserError
 from tests.conftest import assert_date
 from tests.conftest import assert_datetime
 from tests.conftest import assert_duration
@@ -95,6 +98,31 @@ def test_parse_duration() -> None:
     assert_duration(duration, 0, 0, 2, 0, 0, 0, 0)
 
 
+@pytest.mark.parametrize("text", ["PT", "P1DT", "P0DT", "P1Y2MT", "P1.5DT"])
+def test_parse_duration_without_time_components(text: str) -> None:
+    with pytest.raises(ParserError):
+        pendulum.parse(text, strict=True)
+
+
+@pytest.mark.parametrize(
+    ["text", "days", "seconds"],
+    [
+        ("PT0H", 0, 0),
+        ("PT0M", 0, 0),
+        ("PT0S", 0, 0),
+        ("PT0.0S", 0, 0),
+        ("P0D", 0, 0),
+        ("P1DT0S", 1, 0),
+        ("P1DT2S", 1, 2),
+    ],
+)
+def test_parse_duration_time_components(text: str, days: int, seconds: int) -> None:
+    duration = pendulum.parse(text, strict=True)
+
+    assert isinstance(duration, pendulum.Duration)
+    assert_duration(duration, 0, 0, 0, days, 0, 0, seconds)
+
+
 def test_parse_interval() -> None:
     text = "2008-05-11T15:30:00Z/P1Y2M10DT2H30M"