fix: prefixed_entries_range() now works correctly with directory prefixes.

Previously, not all directory prefixes would work as expected due to incorrect
search criteria.

Author: Byron

gix-index/src/access/mod.rs

@@ -198,9 +198,11 @@ impl State {
             return Some(0..self.entries.len());
         }
         let prefix_len = prefix.len();
-        let mut low = self
-            .entries
-            .partition_point(|e| e.path(self).get(..prefix_len).map_or(true, |p| p < prefix));
+        let mut low = self.entries.partition_point(|e| {
+            e.path(self)
+                .get(..prefix_len)
+                .map_or_else(|| e.path(self) <= &prefix[..e.path.len()], |p| p < prefix)
+        });
         let mut high = low
             + self.entries[low..].partition_point(|e| e.path(self).get(..prefix_len).map_or(false, |p| p <= prefix));
 
@@ -211,9 +213,9 @@ impl State {
                 .unwrap_or(low);
         }
         if let Some(high_entry) = self.entries.get(high) {
-            if high_entry.stage() != 3 {
+            if high_entry.stage() != 0 {
                 high = self
-                    .walk_entry_stages(high_entry.path(self), high, Ordering::Greater)
+                    .walk_entry_stages(high_entry.path(self), high, Ordering::Less)
                     .unwrap_or(high);
             }
         }

gix-index/tests/index/access.rs

@@ -114,7 +114,6 @@ fn sort_entries() {
         "we can find the correct entry now"
     );
 
-    check_prefix(&file, "a", &["a", "an initially incorrectly ordered entry"]);
     check_prefix(
         &file,
         "d",
@@ -126,18 +125,44 @@ fn sort_entries() {
         &["d/a", "d/b", "d/c", "d/last/123", "d/last/34", "d/last/6"],
     );
     check_prefix(&file, "d/last", &["d/last/123", "d/last/34", "d/last/6"]);
+    check_prefix(&file, "d/last/", &["d/last/123", "d/last/34", "d/last/6"]);
     check_prefix(&file, "d/las", &["d/last/123", "d/last/34", "d/last/6"]);
+    check_prefix(&file, "d/last/123", &["d/last/123"]);
+    check_prefix(&file, "d/last/34", &["d/last/34"]);
+    check_prefix(&file, "d/last/6", &["d/last/6"]);
+    check_prefix(&file, "x", &["x"]);
+    check_prefix(&file, "a", &["a", "an initially incorrectly ordered entry"]);
+}
+
+#[test]
+fn prefixed_entries() {
+    let mut file = Fixture::Generated("v4_more_files_IEOT").open();
+    let entry = file.entry(0).clone();
+    let new_entry_path = "an initially incorrectly ordered entry".into();
+    file.dangerously_push_entry(entry.stat, entry.id, entry.flags, entry.mode, new_entry_path);
+    file.sort_entries();
+
+    check_prefix(&file, "a", &["a", "an initially incorrectly ordered entry"]);
+    check_prefix(&file, "an", &["an initially incorrectly ordered entry"]);
+    check_prefix(
+        &file,
+        "an initially incorrectly ordered entry",
+        &["an initially incorrectly ordered entry"],
+    );
     check_prefix(&file, "x", &["x"]);
+    check_prefix(&file, "b", &["b"]);
+    check_prefix(&file, "c", &["c"]);
 }
 
 fn check_prefix(index: &gix_index::State, prefix: &str, expected: &[&str]) {
     assert_eq!(
         index
             .prefixed_entries(prefix.into())
-            .expect("present")
+            .unwrap_or_else(|| panic!("{prefix:?} must match at least one entry"))
             .iter()
             .map(|e| e.path(index))
             .collect::<Vec<_>>(),
-        expected
+        expected,
+        "{prefix:?}"
     );
 }