From 24d99c029eff5d5b82aff567f1ad5ede8a8c2576 Mon Sep 17 00:00:00 2001
From: Roman <humbug@deeptown.org>
Date: Tue, 26 Jun 2018 19:37:48 +0400
Subject: [PATCH] Add a verbose error message for BlockingError (#451)

Add a verbose error message for EnterError while trying to run
tokio_threadpool::blocking on a current_thread::Runtime
---
 tokio-threadpool/src/blocking.rs | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/tokio-threadpool/src/blocking.rs b/tokio-threadpool/src/blocking.rs
index c224f9e01..d75ed13ea 100644
--- a/tokio-threadpool/src/blocking.rs
+++ b/tokio-threadpool/src/blocking.rs
@@ -6,7 +6,6 @@ use std::error::Error;
 use std::fmt;
 
 /// Error raised by `blocking`.
-#[derive(Debug)]
 pub struct BlockingError {
     _p: (),
 }
@@ -156,6 +155,14 @@ impl fmt::Display for BlockingError {
     }
 }
 
+impl fmt::Debug for BlockingError {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_struct("BlockingError")
+            .field("reason", &self.description())
+            .finish()
+    }
+}
+
 impl Error for BlockingError {
     fn description(&self) -> &str {
         "`blocking` annotation used from outside the context of a thread pool"