Add initial conversions between Formatter and Names

components/datetime/src/neo.rs

@@ -140,7 +140,7 @@ size_test!(FixedCalendarDateTimeFormatter<icu_calendar::Gregorian, crate::fields
 #[derive(Debug)]
 pub struct FixedCalendarDateTimeFormatter<C: CldrCalendar, FSet: DateTimeNamesMarker> {
     selection: DateTimeZonePatternSelectionData,
-    names: RawDateTimeNames<FSet>,
+    pub(crate) names: RawDateTimeNames<FSet>,
     _calendar: PhantomData<C>,
 }
 
@@ -356,8 +356,8 @@ size_test!(
 #[derive(Debug)]
 pub struct DateTimeFormatter<FSet: DateTimeNamesMarker> {
     selection: DateTimeZonePatternSelectionData,
-    names: RawDateTimeNames<FSet>,
-    calendar: AnyCalendar,
+    pub(crate) names: RawDateTimeNames<FSet>,
+    pub(crate) calendar: AnyCalendar,
 }
 
 impl<FSet: DateTimeMarkers> DateTimeFormatter<FSet>
@@ -469,37 +469,68 @@ where
     {
         let calendar = AnyCalendarLoader::load(loader, (&prefs).into())
             .map_err(DateTimeFormatterLoadError::Data)?;
+        let names = RawDateTimeNames::new_without_number_formatting();
+        Self::try_new_internal_with_calendar_and_names(
+            provider, provider, loader, prefs, field_set, calendar, names,
+        )
+        .map_err(|e| e.0)
+    }
+
+    pub(crate) fn try_new_internal_with_calendar_and_names<P0, P1, L>(
+        provider_p: &P0,
+        provider: &P1,
+        loader: &L,
+        prefs: DateTimeFormatterPreferences,
+        field_set: CompositeFieldSet,
+        calendar: AnyCalendar,
+        mut names: RawDateTimeNames<FSet>,
+    ) -> Result<
+        Self,
+        (
+            DateTimeFormatterLoadError,
+            (AnyCalendar, RawDateTimeNames<FSet>),
+        ),
+    >
+    where
+        P0: ?Sized + AllAnyCalendarPatternDataMarkers<FSet>,
+        P1: ?Sized + AllAnyCalendarFormattingDataMarkers<FSet>,
+        L: DecimalFormatterLoader,
+    {
         let kind = calendar.kind();
         let selection = DateTimeZonePatternSelectionData::try_new_with_skeleton(
-            &AnyCalendarProvider::<<FSet::D as DateDataMarkers>::Skel, _>::new(provider, kind),
-            &<FSet::T as TimeMarkers>::TimeSkeletonPatternsV1::bind(provider),
-            &FSet::GluePatternV1::bind(provider),
+            &AnyCalendarProvider::<<FSet::D as DateDataMarkers>::Skel, _>::new(provider_p, kind),
+            &<FSet::T as TimeMarkers>::TimeSkeletonPatternsV1::bind(provider_p),
+            &FSet::GluePatternV1::bind(provider_p),
             prefs,
             field_set,
-        )
-        .map_err(DateTimeFormatterLoadError::Data)?;
-        let mut names = RawDateTimeNames::new_without_number_formatting();
-        names
-            .load_for_pattern(
-                &AnyCalendarProvider::<<FSet::D as DateDataMarkers>::Year, _>::new(provider, kind),
-                &AnyCalendarProvider::<<FSet::D as DateDataMarkers>::Month, _>::new(provider, kind),
-                &<FSet::D as DateDataMarkers>::WeekdayNamesV1::bind(provider),
-                &<FSet::T as TimeMarkers>::DayPeriodNamesV1::bind(provider),
-                &<FSet::Z as ZoneMarkers>::EssentialsV1::bind(provider),
-                &<FSet::Z as ZoneMarkers>::LocationsV1::bind(provider),
-                &<FSet::Z as ZoneMarkers>::LocationsRootV1::bind(provider),
-                &<FSet::Z as ZoneMarkers>::ExemplarCitiesRootV1::bind(provider),
-                &<FSet::Z as ZoneMarkers>::ExemplarCitiesV1::bind(provider),
-                &<FSet::Z as ZoneMarkers>::GenericLongV1::bind(provider),
-                &<FSet::Z as ZoneMarkers>::GenericShortV1::bind(provider),
-                &<FSet::Z as ZoneMarkers>::SpecificLongV1::bind(provider),
-                &<FSet::Z as ZoneMarkers>::SpecificShortV1::bind(provider),
-                &<FSet::Z as ZoneMarkers>::MetazonePeriodV1::bind(provider),
-                loader, // fixed decimal formatter
-                prefs,
-                selection.pattern_items_for_data_loading(),
-            )
-            .map_err(DateTimeFormatterLoadError::Names)?;
+        );
+        let selection = match selection {
+            Ok(selection) => selection,
+            Err(e) => return Err((DateTimeFormatterLoadError::Data(e), (calendar, names))),
+        };
+        let result = names.load_for_pattern(
+            &AnyCalendarProvider::<<FSet::D as DateDataMarkers>::Year, _>::new(provider, kind),
+            &AnyCalendarProvider::<<FSet::D as DateDataMarkers>::Month, _>::new(provider, kind),
+            &<FSet::D as DateDataMarkers>::WeekdayNamesV1::bind(provider),
+            &<FSet::T as TimeMarkers>::DayPeriodNamesV1::bind(provider),
+            &<FSet::Z as ZoneMarkers>::EssentialsV1::bind(provider),
+            &<FSet::Z as ZoneMarkers>::LocationsV1::bind(provider),
+            &<FSet::Z as ZoneMarkers>::LocationsRootV1::bind(provider),
+            &<FSet::Z as ZoneMarkers>::ExemplarCitiesRootV1::bind(provider),
+            &<FSet::Z as ZoneMarkers>::ExemplarCitiesV1::bind(provider),
+            &<FSet::Z as ZoneMarkers>::GenericLongV1::bind(provider),
+            &<FSet::Z as ZoneMarkers>::GenericShortV1::bind(provider),
+            &<FSet::Z as ZoneMarkers>::SpecificLongV1::bind(provider),
+            &<FSet::Z as ZoneMarkers>::SpecificShortV1::bind(provider),
+            &<FSet::Z as ZoneMarkers>::MetazonePeriodV1::bind(provider),
+            loader, // fixed decimal formatter
+            prefs,
+            selection.pattern_items_for_data_loading(),
+        );
+        match result {
+            Ok(()) => (),
+            Err(e) => return Err((DateTimeFormatterLoadError::Names(e), (calendar, names))),
+        };
         Ok(Self {
             selection,
             names,

components/datetime/src/pattern/mod.rs

@@ -19,6 +19,7 @@ use crate::error::ErrorField;
 pub use formatter::DateTimePatternFormatter;
 pub use formatter::FormattedDateTimePattern;
 use icu_pattern::SinglePlaceholderPattern;
+pub use names::DateTimeNames;
 pub use names::DayPeriodNameLength;
 pub use names::MonthNameLength;
 pub(crate) use names::RawDateTimeNames;