fix round() behaving incorrectly when increment is not passed (#209)

CHANGELOG.rst

@@ -1,6 +1,12 @@
 🚀 Changelog
 ============
 
+0.7.2 (2025-02-25)
+------------------
+
+- Fixed ``round()`` method behaving incorrectly when ``increment`` argument
+  is not passed explicitly (#209)
+
 0.7.1 (2025-02-24)
 ------------------
 

pyproject.toml

@@ -7,7 +7,7 @@ maintainers = [
     {name = "Arie Bovenberg", email = "[email protected]"},
 ]
 readme = "README.md"
-version = "0.7.1"
+version = "0.7.2"
 license = {text = "MIT"}
 description = "Modern datetime library for Python"
 requires-python = ">=3.9"

pysrc/whenever/_pywhenever.py

@@ -32,7 +32,7 @@
 #   - It saves some overhead
 from __future__ import annotations
 
-__version__ = "0.7.1"
+__version__ = "0.7.2"
 
 import enum
 import re

src/instant.rs

@@ -69,9 +69,13 @@ impl Instant {
             nanos,
         }: Time,
     ) -> Self {
-        let secs =
-            date.ord() as i64 * 86400 + hour as i64 * 3600 + minute as i64 * 60 + second as i64;
-        Instant { secs, nanos }
+        Instant {
+            secs: date.ord() as i64 * 86400
+                + hour as i64 * 3600
+                + minute as i64 * 60
+                + second as i64,
+            nanos,
+        }
     }
 
     pub(crate) fn diff(self, other: Self) -> TimeDelta {

src/round.rs

@@ -116,6 +116,18 @@ impl Unit {
                 .ok_or_value_err("Increment must be 1 for 'day' unit"),
         }
     }
+
+    unsafe fn default_increment(self) -> i64 {
+        match self {
+            Unit::Nanosecond => 1,
+            Unit::Microsecond => 1_000,
+            Unit::Millisecond => 1_000_000,
+            Unit::Second => 1_000_000_000,
+            Unit::Minute => 60 * 1_000_000_000,
+            Unit::Hour => 3_600 * 1_000_000_000,
+            Unit::Day => 86_400 * 1_000_000_000,
+        }
+    }
 }
 
 // NOTE: the caller still needs to check whenever 'day' is valid for them
@@ -216,7 +228,7 @@ pub(crate) unsafe fn parse_args(
     let increment = arg_obj[1]
         .map(|v| unit.increment_from_py(v.as_ptr(), hours_largest_unit))
         .transpose()?
-        .unwrap_or(1_000_000_000);
+        .unwrap_or_else(|| unit.default_increment());
     let mode = arg_obj[2]
         .map(|v| {
             Mode::from_py(

tests/test_time_delta.py

@@ -768,6 +768,10 @@ def test_default_half_even_seconds(self):
             seconds=4
         )
 
+    def test_default_increment(self):
+        d = TimeDelta(seconds=2, nanoseconds=800)
+        assert d.round("microsecond") == TimeDelta(seconds=2, microseconds=1)
+
     def test_invalid_unit(self):
         t = TimeDelta.ZERO
         with pytest.raises(ValueError, match="Invalid.*unit.*foo"):

tests/test_zoned_datetime.py

@@ -2526,6 +2526,15 @@ def test_default(self):
             2023, 7, 14, 1, 2, 8, tz="Europe/Paris"
         )
 
+    # TODO: test this robustly on all classes
+    def test_default_increment(self):
+        d = ZonedDateTime(
+            2023, 7, 14, 1, 2, 3, nanosecond=800_000, tz="Europe/Paris"
+        )
+        assert d.round("millisecond") == ZonedDateTime(
+            2023, 7, 14, 1, 2, 3, nanosecond=1_000_000, tz="Europe/Paris"
+        )
+
     def test_invalid_mode(self):
         d = ZonedDateTime(
             2023, 7, 14, 1, 2, 3, nanosecond=4_000, tz="Europe/Paris"