Handle negative nano seconds

Author: snaggen

crates/jiff-aws/src/lib.rs

@@ -73,18 +73,18 @@ impl ConvertJiffTypes for DateTime {
     type Error = jiff::Error;
 
     fn from_timestamp(timestamp: Timestamp) -> Self {
-        DateTime::from_secs_and_nanos(
-            timestamp.as_second(),
-            timestamp.subsec_nanosecond() as u32,
-        )
+        let nanos = if timestamp.subsec_nanosecond() < 0 {
+            (1_000_000_000 + timestamp.subsec_nanosecond()) as u32
+        } else {
+            timestamp.subsec_nanosecond() as u32
+        };
+
+        DateTime::from_secs_and_nanos(timestamp.as_second(), nanos)
     }
 
     fn from_zoned(zoned: Zoned) -> Self {
         let timestamp = zoned.timestamp();
-        DateTime::from_secs_and_nanos(
-            timestamp.as_second(),
-            timestamp.subsec_nanosecond() as u32,
-        )
+        Self::from_timestamp(timestamp)
     }
 
     fn try_into_zoned(self) -> Result<Zoned, Self::Error> {