Make TimeZone::identifier() infallible

src/builtins/core/instant.rs

@@ -121,7 +121,7 @@ const NANOSECONDS_PER_HOUR: i64 = 60 * NANOSECONDS_PER_MINUTE;
 ///
 /// // Convert to a zoned date-time for display in local time
 /// let zdt = instant.to_zoned_date_time_iso(timezone);
-/// assert_eq!(zdt.timezone().identifier().unwrap(), "America/New_York");
+/// assert_eq!(zdt.timezone().identifier(), "America/New_York");
 /// assert_eq!(zdt.calendar().identifier(), "iso8601");
 /// ```
 ///

src/builtins/core/timezone.rs

@@ -50,7 +50,8 @@ impl UtcOffset {
         }
     }
 
-    pub fn to_string(&self) -> TemporalResult<String> {
+    #[allow(clippy::inherent_to_string)]
+    pub fn to_string(&self) -> String {
         let sign = if self.0 < 0 {
             Sign::Negative
         } else {
@@ -69,7 +70,7 @@ impl UtcOffset {
                 include_sep: true,
             },
         };
-        Ok(formattable_offset.to_string())
+        formattable_offset.to_string()
     }
 }
 
@@ -138,9 +139,9 @@ impl TimeZone {
     }
 
     /// Returns the current `TimeZoneSlot`'s identifier.
-    pub fn identifier(&self) -> TemporalResult<String> {
+    pub fn identifier(&self) -> String {
         match self {
-            TimeZone::IanaIdentifier(s) => Ok(s.clone()),
+            TimeZone::IanaIdentifier(s) => s.clone(),
             TimeZone::UtcOffset(offset) => offset.to_string(),
         }
     }
@@ -468,18 +469,18 @@ mod tests {
     fn from_and_to_string() {
         let src = "+09:30";
         let tz = TimeZone::try_from_identifier_str(src).unwrap();
-        assert_eq!(tz.identifier().unwrap(), src);
+        assert_eq!(tz.identifier(), src);
 
         let src = "-09:30";
         let tz = TimeZone::try_from_identifier_str(src).unwrap();
-        assert_eq!(tz.identifier().unwrap(), src);
+        assert_eq!(tz.identifier(), src);
 
         let src = "-12:30";
         let tz = TimeZone::try_from_identifier_str(src).unwrap();
-        assert_eq!(tz.identifier().unwrap(), src);
+        assert_eq!(tz.identifier(), src);
 
         let src = "America/New_York";
         let tz = TimeZone::try_from_identifier_str(src).unwrap();
-        assert_eq!(tz.identifier().unwrap(), src);
+        assert_eq!(tz.identifier(), src);
     }
 }

src/builtins/core/zoneddatetime.rs

@@ -123,7 +123,7 @@ impl PartialZonedDateTime {
 ///
 /// assert_eq!(zdt.epoch_milliseconds(), 0);
 /// assert_eq!(zdt.epoch_nanoseconds().as_i128(), 0);
-/// assert_eq!(zdt.timezone().identifier().unwrap(), "UTC");
+/// assert_eq!(zdt.timezone().identifier(), "UTC");
 /// assert_eq!(zdt.calendar().identifier(), "iso8601");
 /// ```
 ///
@@ -193,7 +193,7 @@ impl PartialZonedDateTime {
 /// ).unwrap();
 ///
 /// // Now we have an exact moment in time in the LA timezone
-/// assert_eq!(zdt.timezone().identifier().unwrap(), "America/Los_Angeles");
+/// assert_eq!(zdt.timezone().identifier(), "America/Los_Angeles");
 /// ```
 ///
 /// ### String formatting (requires provider)
@@ -1261,7 +1261,7 @@ impl ZonedDateTime {
         let offset = self.tz.get_offset_nanos_for(result, provider)?;
         let datetime = self.tz.get_iso_datetime_for(&rounded_instant, provider)?;
         let (sign, hour, minute) = nanoseconds_to_formattable_offset_minutes(offset)?;
-        let timezone_id = self.timezone().identifier()?;
+        let timezone_id = self.timezone().identifier();
 
         let ixdtf_string = IxdtfStringBuilder::default()
             .with_date(datetime.date)

temporal_capi/src/time_zone.rs

@@ -35,15 +35,13 @@ pub mod ffi {
                 .map_err(Into::into)
         }
 
-        pub fn identifier(&self, write: &mut DiplomatWrite) -> Result<(), TemporalError> {
+        pub fn identifier(&self, write: &mut DiplomatWrite) {
             // TODO ideally this would use Writeable instead of allocating
-            let s = self.0.identifier()?;
+            let s = self.0.identifier();
 
             // This can only fail in cases where the DiplomatWriteable is capped, we
             // don't care about that.
             let _ = write.write_str(&s);
-
-            Ok(())
         }
 
         #[allow(clippy::should_implement_trait)]