1 files changed, 48 insertions, 0 deletions
diff --git a/third_party/rust/thiserror/src/aserror.rs b/third_party/rust/thiserror/src/aserror.rs
new file mode 100644
index 0000000000..5fea84ef88
--- /dev/null
+++ b/third_party/rust/thiserror/src/aserror.rs
@@ -0,0 +1,48 @@
+use std::error::Error;
+use std::panic::UnwindSafe;
+
+pub trait AsDynError<'a>: Sealed {
+    fn as_dyn_error(&self) -> &(dyn Error + 'a);
+}
+
+impl<'a, T: Error + 'a> AsDynError<'a> for T {
+    #[inline]
+    fn as_dyn_error(&self) -> &(dyn Error + 'a) {
+        self
+    }
+}
+
+impl<'a> AsDynError<'a> for dyn Error + 'a {
+    #[inline]
+    fn as_dyn_error(&self) -> &(dyn Error + 'a) {
+        self
+    }
+}
+
+impl<'a> AsDynError<'a> for dyn Error + Send + 'a {
+    #[inline]
+    fn as_dyn_error(&self) -> &(dyn Error + 'a) {
+        self
+    }
+}
+
+impl<'a> AsDynError<'a> for dyn Error + Send + Sync + 'a {
+    #[inline]
+    fn as_dyn_error(&self) -> &(dyn Error + 'a) {
+        self
+    }
+}
+
+impl<'a> AsDynError<'a> for dyn Error + Send + Sync + UnwindSafe + 'a {
+    #[inline]
+    fn as_dyn_error(&self) -> &(dyn Error + 'a) {
+        self
+    }
+}
+
+pub trait Sealed {}
+impl<'a, T: Error + 'a> Sealed for T {}
+impl<'a> Sealed for dyn Error + 'a {}
+impl<'a> Sealed for dyn Error + Send + 'a {}
+impl<'a> Sealed for dyn Error + Send + Sync + 'a {}
+impl<'a> Sealed for dyn Error + Send + Sync + UnwindSafe + 'a {}