1 files changed, 46 insertions, 0 deletions
diff --git a/third_party/rust/crossbeam-queue/src/err.rs b/third_party/rust/crossbeam-queue/src/err.rs
new file mode 100644
index 0000000000..fcc84bb28b
--- /dev/null
+++ b/third_party/rust/crossbeam-queue/src/err.rs
@@ -0,0 +1,46 @@
+use std::error;
+use std::fmt;
+
+/// Error which occurs when popping from an empty queue.
+#[derive(Clone, Copy, Eq, PartialEq)]
+pub struct PopError;
+
+impl fmt::Debug for PopError {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        "PopError".fmt(f)
+    }
+}
+
+impl fmt::Display for PopError {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        "popping from an empty queue".fmt(f)
+    }
+}
+
+impl error::Error for PopError {
+    fn description(&self) -> &str {
+        "popping from an empty queue"
+    }
+}
+
+/// Error which occurs when pushing into a full queue.
+#[derive(Clone, Copy, Eq, PartialEq)]
+pub struct PushError<T>(pub T);
+
+impl<T> fmt::Debug for PushError<T> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        "PushError(..)".fmt(f)
+    }
+}
+
+impl<T> fmt::Display for PushError<T> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        "pushing into a full queue".fmt(f)
+    }
+}
+
+impl<T: Send> error::Error for PushError<T> {
+    fn description(&self) -> &str {
+        "pushing into a full queue"
+    }
+}