extract out locales for a later change

src/format/mod.rs

@@ -441,6 +441,63 @@ const TOO_SHORT: ParseError = ParseError(ParseErrorKind::TooShort);
 const TOO_LONG: ParseError = ParseError(ParseErrorKind::TooLong);
 const BAD_FORMAT: ParseError = ParseError(ParseErrorKind::BadFormat);
 
+#[cfg(any(feature = "alloc", feature = "std", test))]
+struct Locales {
+    short_months: &'static [&'static str],
+    long_months: &'static [&'static str],
+    short_weekdays: &'static [&'static str],
+    long_weekdays: &'static [&'static str],
+    am_pm: &'static [&'static str],
+}
+
+#[cfg(any(feature = "alloc", feature = "std", test))]
+impl Locales {
+    fn new(_locale: Option<Locale>) -> Self {
+        #[cfg(feature = "unstable-locales")]
+        {
+            let locale = _locale.unwrap_or(Locale::POSIX);
+            Self {
+                short_months: locales::short_months(locale),
+                long_months: locales::long_months(locale),
+                short_weekdays: locales::short_weekdays(locale),
+                long_weekdays: locales::long_weekdays(locale),
+                am_pm: locales::am_pm(locale),
+            }
+        }
+        #[cfg(not(feature = "unstable-locales"))]
+        Self {
+            short_months: &[
+                "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec",
+            ],
+            long_months: &[
+                "January",
+                "February",
+                "March",
+                "April",
+                "May",
+                "June",
+                "July",
+                "August",
+                "September",
+                "October",
+                "November",
+                "December",
+            ],
+            short_weekdays: &["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"],
+            long_weekdays: &[
+                "Sunday",
+                "Monday",
+                "Tuesday",
+                "Wednesday",
+                "Thursday",
+                "Friday",
+                "Saturday",
+            ],
+            am_pm: &["AM", "PM"],
+        }
+    }
+}
+
 /// Formats single formatting item
 #[cfg(any(feature = "alloc", feature = "std", test))]
 #[cfg_attr(docsrs, doc(cfg(any(feature = "alloc", feature = "std"))))]
@@ -463,45 +520,9 @@ fn format_inner<'a>(
     time: Option<&NaiveTime>,
     off: Option<&(String, FixedOffset)>,
     item: &Item<'a>,
-    _locale: Option<Locale>,
+    locale: Option<Locale>,
 ) -> fmt::Result {
-    #[cfg(feature = "unstable-locales")]
-    let (short_months, long_months, short_weekdays, long_weekdays, am_pm, am_pm_lowercase) = {
-        let locale = _locale.unwrap_or(Locale::POSIX);
-        let am_pm = locales::am_pm(locale);
-        (
-            locales::short_months(locale),
-            locales::long_months(locale),
-            locales::short_weekdays(locale),
-            locales::long_weekdays(locale),
-            am_pm,
-            &[am_pm[0].to_lowercase(), am_pm[1].to_lowercase()],
-        )
-    };
-    #[cfg(not(feature = "unstable-locales"))]
-    let (short_months, long_months, short_weekdays, long_weekdays, am_pm, am_pm_lowercase) = {
-        (
-            &["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"],
-            &[
-                "January",
-                "February",
-                "March",
-                "April",
-                "May",
-                "June",
-                "July",
-                "August",
-                "September",
-                "October",
-                "November",
-                "December",
-            ],
-            &["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"],
-            &["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"],
-            &["AM", "PM"],
-            &["am", "pm"],
-        )
-    };
+    let locale = Locales::new(locale);
 
     use num_integer::{div_floor, mod_floor};
 
@@ -581,35 +602,38 @@ fn format_inner<'a>(
             let ret =
                 match *spec {
                     ShortMonthName => date.map(|d| {
-                        result.push_str(short_months[d.month0() as usize]);
+                        result.push_str(locale.short_months[d.month0() as usize]);
                         Ok(())
                     }),
                     LongMonthName => date.map(|d| {
-                        result.push_str(long_months[d.month0() as usize]);
+                        result.push_str(locale.long_months[d.month0() as usize]);
                         Ok(())
                     }),
                     ShortWeekdayName => date.map(|d| {
-                        result
-                            .push_str(short_weekdays[d.weekday().num_days_from_sunday() as usize]);
+                        result.push_str(
+                            locale.short_weekdays[d.weekday().num_days_from_sunday() as usize],
+                        );
                         Ok(())
                     }),
                     LongWeekdayName => date.map(|d| {
-                        result.push_str(long_weekdays[d.weekday().num_days_from_sunday() as usize]);
+                        result.push_str(
+                            locale.long_weekdays[d.weekday().num_days_from_sunday() as usize],
+                        );
                         Ok(())
                     }),
                     LowerAmPm => time.map(|t| {
-                        #[cfg_attr(feature = "cargo-clippy", allow(clippy::useless_asref))]
-                        {
-                            result.push_str(if t.hour12().0 {
-                                am_pm_lowercase[1].as_ref()
-                            } else {
-                                am_pm_lowercase[0].as_ref()
-                            });
+                        let ampm = if t.hour12().0 { locale.am_pm[1] } else { locale.am_pm[0] };
+                        for char in ampm.chars() {
+                            result.extend(char.to_lowercase())
                         }
                         Ok(())
                     }),
                     UpperAmPm => time.map(|t| {
-                        result.push_str(if t.hour12().0 { am_pm[1] } else { am_pm[0] });
+                        result.push_str(if t.hour12().0 {
+                            locale.am_pm[1]
+                        } else {
+                            locale.am_pm[0]
+                        });
                         Ok(())
                     }),
                     Nanosecond => time.map(|t| {
@@ -680,9 +704,9 @@ fn format_inner<'a>(
                             write!(
                                 result,
                                 "{}, {:02} {} {:04} {:02}:{:02}:{:02} ",
-                                short_weekdays[d.weekday().num_days_from_sunday() as usize],
+                                locale.short_weekdays[d.weekday().num_days_from_sunday() as usize],
                                 d.day(),
-                                short_months[d.month0() as usize],
+                                locale.short_months[d.month0() as usize],
                                 d.year(),
                                 t.hour(),
                                 t.minute(),