1 files changed, 57 insertions, 0 deletions
diff --git a/vendor/thread_local/src/unreachable.rs b/vendor/thread_local/src/unreachable.rs
new file mode 100644
index 000000000..db4d831ac
--- /dev/null
+++ b/vendor/thread_local/src/unreachable.rs
@@ -0,0 +1,57 @@
+// Copyright 2017 Amanieu d'Antras
+//
+// Licensed under the Apache License, Version 2.0, <LICENSE-APACHE or
+// http://apache.org/licenses/LICENSE-2.0> or the MIT license <LICENSE-MIT or
+// http://opensource.org/licenses/MIT>, at your option. This file may not be
+// copied, modified, or distributed except according to those terms.
+
+use std::hint::unreachable_unchecked;
+
+/// An extension trait for `Option<T>` providing unchecked unwrapping methods.
+pub trait UncheckedOptionExt<T> {
+    /// Get the value out of this Option without checking for None.
+    unsafe fn unchecked_unwrap(self) -> T;
+
+    /// Assert that this Option is a None to the optimizer.
+    unsafe fn unchecked_unwrap_none(self);
+}
+
+/// An extension trait for `Result<T, E>` providing unchecked unwrapping methods.
+pub trait UncheckedResultExt<T, E> {
+    /// Get the value out of this Result without checking for Err.
+    unsafe fn unchecked_unwrap_ok(self) -> T;
+
+    /// Get the error out of this Result without checking for Ok.
+    unsafe fn unchecked_unwrap_err(self) -> E;
+}
+
+impl<T> UncheckedOptionExt<T> for Option<T> {
+    unsafe fn unchecked_unwrap(self) -> T {
+        match self {
+            Some(x) => x,
+            None => unreachable_unchecked(),
+        }
+    }
+
+    unsafe fn unchecked_unwrap_none(self) {
+        if self.is_some() {
+            unreachable_unchecked()
+        }
+    }
+}
+
+impl<T, E> UncheckedResultExt<T, E> for Result<T, E> {
+    unsafe fn unchecked_unwrap_ok(self) -> T {
+        match self {
+            Ok(x) => x,
+            Err(_) => unreachable_unchecked(),
+        }
+    }
+
+    unsafe fn unchecked_unwrap_err(self) -> E {
+        match self {
+            Ok(_) => unreachable_unchecked(),
+            Err(e) => e,
+        }
+    }
+}