1 files changed, 78 insertions, 0 deletions
diff --git a/vendor/indexmap/src/util.rs b/vendor/indexmap/src/util.rs
new file mode 100644
index 00000000..8b3b2b48
--- /dev/null
+++ b/vendor/indexmap/src/util.rs
@@ -0,0 +1,78 @@
+use core::ops::{Bound, Range, RangeBounds};
+
+pub(crate) fn third<A, B, C>(t: (A, B, C)) -> C {
+    t.2
+}
+
+#[track_caller]
+pub(crate) fn simplify_range<R>(range: R, len: usize) -> Range<usize>
+where
+    R: RangeBounds<usize>,
+{
+    let start = match range.start_bound() {
+        Bound::Unbounded => 0,
+        Bound::Included(&i) if i <= len => i,
+        Bound::Excluded(&i) if i < len => i + 1,
+        Bound::Included(i) | Bound::Excluded(i) => {
+            panic!("range start index {i} out of range for slice of length {len}")
+        }
+    };
+    let end = match range.end_bound() {
+        Bound::Unbounded => len,
+        Bound::Excluded(&i) if i <= len => i,
+        Bound::Included(&i) if i < len => i + 1,
+        Bound::Included(i) | Bound::Excluded(i) => {
+            panic!("range end index {i} out of range for slice of length {len}")
+        }
+    };
+    if start > end {
+        panic!(
+            "range start index {:?} should be <= range end index {:?}",
+            range.start_bound(),
+            range.end_bound()
+        );
+    }
+    start..end
+}
+
+pub(crate) fn try_simplify_range<R>(range: R, len: usize) -> Option<Range<usize>>
+where
+    R: RangeBounds<usize>,
+{
+    let start = match range.start_bound() {
+        Bound::Unbounded => 0,
+        Bound::Included(&i) if i <= len => i,
+        Bound::Excluded(&i) if i < len => i + 1,
+        _ => return None,
+    };
+    let end = match range.end_bound() {
+        Bound::Unbounded => len,
+        Bound::Excluded(&i) if i <= len => i,
+        Bound::Included(&i) if i < len => i + 1,
+        _ => return None,
+    };
+    if start > end {
+        return None;
+    }
+    Some(start..end)
+}
+
+// Generic slice equality -- copied from the standard library but adding a custom comparator,
+// allowing for our `Bucket` wrapper on either or both sides.
+pub(crate) fn slice_eq<T, U>(left: &[T], right: &[U], eq: impl Fn(&T, &U) -> bool) -> bool {
+    if left.len() != right.len() {
+        return false;
+    }
+
+    // Implemented as explicit indexing rather
+    // than zipped iterators for performance reasons.
+    // See PR https://github.com/rust-lang/rust/pull/116846
+    for i in 0..left.len() {
+        // bound checks are optimized away
+        if !eq(&left[i], &right[i]) {
+            return false;
+        }
+    }
+
+    true
+}