From da743ec4868d128313ea026a776d40086f7941e7 Mon Sep 17 00:00:00 2001
From: Divma <26765164+divagant-martian@users.noreply.github.com>
Date: Mon, 24 Jul 2023 14:52:51 -0500
Subject: [PATCH] fix(swarm): display cause of denied listen error

The display of `ListenError` could be more helpful. The inner `cause` already implements `Error` which in turn requires `Display`. This is then just a matter of using said impl requirement to get an useful display

Pull-Request: #4232.
---
 Cargo.lock         | 2 +-
 Cargo.toml         | 2 +-
 swarm/CHANGELOG.md | 6 ++++++
 swarm/Cargo.toml   | 2 +-
 swarm/src/lib.rs   | 4 ++--
 5 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 6c215e16c84..e89447b4edb 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3150,7 +3150,7 @@ dependencies = [
 
 [[package]]
 name = "libp2p-swarm"
-version = "0.43.1"
+version = "0.43.2"
 dependencies = [
  "async-std",
  "either",
diff --git a/Cargo.toml b/Cargo.toml
index 5a3885ed161..07ac8ab9e85 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -87,7 +87,7 @@ libp2p-quic = { version = "0.8.0-alpha", path = "transports/quic" }
 libp2p-relay = { version = "0.16.1", path = "protocols/relay" }
 libp2p-rendezvous = { version = "0.13.0", path = "protocols/rendezvous" }
 libp2p-request-response = { version = "0.25.1", path = "protocols/request-response" }
-libp2p-swarm = { version = "0.43.1", path = "swarm" }
+libp2p-swarm = { version = "0.43.2", path = "swarm" }
 libp2p-swarm-derive = { version = "0.33.0", path = "swarm-derive" }
 libp2p-swarm-test = { version = "0.2.0", path = "swarm-test" }
 libp2p-tcp = { version = "0.40.0", path = "transports/tcp" }
diff --git a/swarm/CHANGELOG.md b/swarm/CHANGELOG.md
index ecf49a38236..b5c33d90eb4 100644
--- a/swarm/CHANGELOG.md
+++ b/swarm/CHANGELOG.md
@@ -1,3 +1,9 @@
+## 0.43.2 - unreleased
+- Display the cause of a `ListenError::Denied`.
+  See [PR 4232]
+
+[PR 4232]: https://github.com/libp2p/rust-libp2p/pull/4158
+
 ## 0.43.1
 
 - Do not announce external address candidate before address translation, unless translation does not apply.
diff --git a/swarm/Cargo.toml b/swarm/Cargo.toml
index 10bd747e4c8..752491cda7e 100644
--- a/swarm/Cargo.toml
+++ b/swarm/Cargo.toml
@@ -3,7 +3,7 @@ name = "libp2p-swarm"
 edition = "2021"
 rust-version = { workspace = true }
 description = "The libp2p swarm"
-version = "0.43.1"
+version = "0.43.2"
 authors = ["Parity Technologies <admin@parity.io>"]
 license = "MIT"
 repository = "https://github.com/libp2p/rust-libp2p"
diff --git a/swarm/src/lib.rs b/swarm/src/lib.rs
index f8c8e855bd5..867e49410c5 100644
--- a/swarm/src/lib.rs
+++ b/swarm/src/lib.rs
@@ -1684,8 +1684,8 @@ impl fmt::Display for ListenError {
             ListenError::Transport(_) => {
                 write!(f, "Listen error: Failed to negotiate transport protocol(s)")
             }
-            ListenError::Denied { .. } => {
-                write!(f, "Listen error")
+            ListenError::Denied { cause } => {
+                write!(f, "Listen error: Denied: {cause}")
             }
             ListenError::LocalPeerId { endpoint } => {
                 write!(f, "Listen error: Local peer ID at {endpoint:?}.")