sort: fix locale collation strength for hyphen ordering (#12677)

Set Strength::Quaternary on the ICU collator so that punctuation like
hyphens sort before alphanumerics in UTF-8 locales, matching GNU sort
behavior.

Fixes #12542

src/uucore/src/lib/features/i18n/collator.rs

@@ -70,6 +70,7 @@ pub fn init_locale_collation() -> bool {
     // UTF-8 locale - initialize collator with Shifted mode to match GNU behavior
     let mut opts = CollatorOptions::default();
     opts.alternate_handling = Some(AlternateHandling::Shifted);
+    opts.strength = Some(Strength::Quaternary);
 
     try_init_collator(opts)
 }

tests/by-util/test_sort.rs

@@ -3017,4 +3017,23 @@ fn test_consistent_sorting_with_i18n_collate() {
         .stdout_is(expected_output);
 }
 
+#[test]
+fn test_sort_locale_punctuation_weights() {
+    // Test for issue #12542
+    let input = "file10\nfile-10\n";
+    let expected_output = "file-10\nfile10\n";
+
+    new_ucmd!()
+        .env("LC_ALL", "en_US.UTF-8")
+        .pipe_in(input)
+        .succeeds()
+        .stdout_is(expected_output);
+
+    new_ucmd!()
+        .env("LC_ALL", "C")
+        .pipe_in(input)
+        .succeeds()
+        .stdout_is(expected_output);
+}
+
 /* spell-checker: enable */