1 files changed, 113 insertions, 0 deletions
diff --git a/third_party/rust/phf/src/set.rs b/third_party/rust/phf/src/set.rs
new file mode 100644
index 0000000000..9588d4a747
--- /dev/null
+++ b/third_party/rust/phf/src/set.rs
@@ -0,0 +1,113 @@
+//! An immutable set constructed at compile time.
+use core::borrow::Borrow;
+use core::iter::IntoIterator;
+use core::fmt;
+
+use crate::{map, Map, PhfHash};
+
+/// An immutable set constructed at compile time.
+///
+/// ## Note
+///
+/// The fields of this struct are public so that they may be initialized by the
+/// `phf_set!` macro and code generation. They are subject to change at any
+/// time and should never be accessed directly.
+pub struct Set<T: 'static> {
+    #[doc(hidden)]
+    pub map: Map<T, ()>,
+}
+
+impl<T> fmt::Debug for Set<T> where T: fmt::Debug {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        fmt.debug_set().entries(self).finish()
+    }
+}
+
+impl<T> Set<T> {
+    /// Returns the number of elements in the `Set`.
+    pub fn len(&self) -> usize {
+        self.map.len()
+    }
+
+    /// Returns true if the `Set` contains no elements.
+    pub fn is_empty(&self) -> bool {
+        self.len() == 0
+    }
+
+    /// Returns a reference to the set's internal static instance of the given
+    /// key.
+    ///
+    /// This can be useful for interning schemes.
+    pub fn get_key<U: ?Sized>(&self, key: &U) -> Option<&T>
+        where U: Eq + PhfHash,
+              T: Borrow<U>
+    {
+        self.map.get_key(key)
+    }
+
+    /// Returns true if `value` is in the `Set`.
+    pub fn contains<U: ?Sized>(&self, value: &U) -> bool
+        where U: Eq + PhfHash,
+              T: Borrow<U>
+    {
+        self.map.contains_key(value)
+    }
+
+    /// Returns an iterator over the values in the set.
+    ///
+    /// Values are returned in an arbitrary but fixed order.
+    pub fn iter<'a>(&'a self) -> Iter<'a, T> {
+        Iter { iter: self.map.keys() }
+    }
+}
+
+impl<T> Set<T> where T: Eq + PhfHash {
+    /// Returns true if `other` shares no elements with `self`.
+    pub fn is_disjoint(&self, other: &Set<T>) -> bool {
+        !self.iter().any(|value| other.contains(value))
+    }
+
+    /// Returns true if `other` contains all values in `self`.
+    pub fn is_subset(&self, other: &Set<T>) -> bool {
+        self.iter().all(|value| other.contains(value))
+    }
+
+    /// Returns true if `self` contains all values in `other`.
+    pub fn is_superset(&self, other: &Set<T>) -> bool {
+        other.is_subset(self)
+    }
+}
+
+impl<'a, T> IntoIterator for &'a Set<T> {
+    type Item = &'a T;
+    type IntoIter = Iter<'a, T>;
+
+    fn into_iter(self) -> Iter<'a, T> {
+        self.iter()
+    }
+}
+
+/// An iterator over the values in a `Set`.
+pub struct Iter<'a, T: 'static> {
+    iter: map::Keys<'a, T, ()>,
+}
+
+impl<'a, T> Iterator for Iter<'a, T> {
+    type Item = &'a T;
+
+    fn next(&mut self) -> Option<&'a T> {
+        self.iter.next()
+    }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.iter.size_hint()
+    }
+}
+
+impl<'a, T> DoubleEndedIterator for Iter<'a, T> {
+    fn next_back(&mut self) -> Option<&'a T> {
+        self.iter.next_back()
+    }
+}
+
+impl<'a, T> ExactSizeIterator for Iter<'a, T> {}