i18n: Hebrew on one line, its sign held left, CLDR's short years

gpui 0.2.2 wraps shaped glyphs in the order they are drawn, so a
right-to-left line that wraps comes out garbled. The demo's Hebrew
lines are Ellipses, which cut by characters, and an Ellipsis now sits
by its text's alignment, so a short line under text_right lies at the
right; the editor's completion details take the side they ask for. A
right-to-left locale leads a minus with a left-to-right mark, as CLDR
does, so the sign stays at the digits' left inside Hebrew. en-US and
de-DE write CLDR's two-digit year. The repeated-key and second-catalog
guards have tests.

src/i18n/locale.rs

@@ -61,7 +61,7 @@ pub const LOCALES: [Locale; 7] = [
         "en-US",
         "English (US)",
         (',', '.'),
-        "%-m/%-d/%Y",
+        "%-m/%-d/%y",
         Direction::Ltr,
     ),
     locale(
@@ -71,7 +71,7 @@ pub const LOCALES: [Locale; 7] = [
         "%d/%m/%Y",
         Direction::Ltr,
     ),
-    locale("de-DE", "Deutsch", ('.', ','), "%d.%m.%Y", Direction::Ltr),
+    locale("de-DE", "Deutsch", ('.', ','), "%d.%m.%y", Direction::Ltr),
     locale(
         "fr-FR",
         "Français",
@@ -93,9 +93,13 @@ impl Locale {
             .unwrap_or_else(|| panic!("no locale {tag:?}"))
     }
 
-    /// `value` with this locale's separators.
+    /// `value` with this locale's separators; a right-to-left locale leads its sign with a left-to-right mark, as CLDR does.
     pub fn number(self, value: f64, decimals: usize) -> String {
-        format::number(value, decimals, self.separators)
+        let number = format::number(value, decimals, self.separators);
+        match (self.direction, number.starts_with(format::MINUS)) {
+            (Direction::Rtl, true) => format!("\u{200e}{number}"),
+            _ => number,
+        }
     }
 
     /// The day `at` falls on in `zone`, written as this locale writes dates.

src/i18n/tests.rs

@@ -53,6 +53,20 @@ fn a_catalog_with_a_stray_key_fails() {
         .catalog("de-DE", &[("hi", "Hallo"), ("bye", "Tschüss")]);
 }
 
+#[test]
+#[should_panic(expected = "en-US repeats a key")]
+fn a_repeated_key_fails() {
+    I18n::new("en-US").catalog("en-US", &[("hi", "Hello"), ("hi", "Hey")]);
+}
+
+#[test]
+#[should_panic(expected = "en-US has a catalog")]
+fn a_second_catalog_for_a_locale_fails() {
+    I18n::new("en-US")
+        .catalog("en-US", &[("hi", "Hello")])
+        .catalog("en-US", &[("hi", "Hey")]);
+}
+
 #[test]
 #[should_panic(expected = "no locale \"xx-XX\"")]
 fn an_unlisted_locale_fails() {
@@ -76,9 +90,9 @@ fn locales_write_their_own_numbers_and_dates() {
     assert_eq!(
         cases,
         [
-            ("en-US", "−1,234,567.89".into(), "9/1/2026".into()),
+            ("en-US", "−1,234,567.89".into(), "9/1/26".into()),
             ("en-GB", "−1,234,567.89".into(), "01/09/2026".into()),
-            ("de-DE", "−1.234.567,89".into(), "01.09.2026".into()),
+            ("de-DE", "−1.234.567,89".into(), "01.09.26".into()),
             (
                 "fr-FR",
                 "−1\u{202f}234\u{202f}567,89".into(),
@@ -86,7 +100,7 @@ fn locales_write_their_own_numbers_and_dates() {
             ),
             ("ja-JP", "−1,234,567.89".into(), "2026/09/01".into()),
             ("zh-CN", "−1,234,567.89".into(), "2026/9/1".into()),
-            ("he-IL", "−1,234,567.89".into(), "1.9.2026".into()),
+            ("he-IL", "\u{200e}−1,234,567.89".into(), "1.9.2026".into()),
         ]
     );
     let rtl: Vec<_> = LOCALES
@@ -94,6 +108,11 @@ fn locales_write_their_own_numbers_and_dates() {
         .filter(|locale| locale.direction == Direction::Rtl)
         .collect();
     assert_eq!(rtl, [&Locale::of("he-IL")]);
+    assert_eq!(
+        Locale::of("he-IL").number(3.5, 1),
+        "3.5",
+        "a gain takes no mark"
+    );
 }
 
 #[cfg(feature = "test-support")]