commit 805bb08a3846d2bfda631d3e58f1ecf577f0861e
Author: Xavier Shay <xavier@squareup.com>
Date:   Wed Aug 13 15:24:45 2014 -0700

    More descriptive error message when net/http fails to connect to a server.

diff --git a/lib/net/http.rb b/lib/net/http.rb
index aceb530..b3d096f 100644
--- a/lib/net/http.rb
+++ b/lib/net/http.rb
@@ -876,7 +876,12 @@ module Net   #:nodoc:
 
       D "opening connection to #{conn_address}:#{conn_port}..."
       s = Timeout.timeout(@open_timeout, Net::OpenTimeout) {
-        TCPSocket.open(conn_address, conn_port, @local_host, @local_port)
+        begin
+          TCPSocket.open(conn_address, conn_port, @local_host, @local_port)
+        rescue => e
+          raise e, "Failed to open TCP connection to " +
+            "#{conn_address}:#{conn_port} (#{e.message})"
+        end
       }
       s.setsockopt(Socket::IPPROTO_TCP, Socket::TCP_NODELAY, 1)
       D "opened"
diff --git a/test/net/http/test_http.rb b/test/net/http/test_http.rb
index 704456f..94d1a6b 100644
--- a/test/net/http/test_http.rb
+++ b/test/net/http/test_http.rb
@@ -189,6 +189,15 @@ class TestNetHTTP < Test::Unit::TestCase
     end
   end
 
+  def test_failure_message_includes_failed_domain_and_port
+    begin
+      Net::HTTP.get(URI.parse("http://doesnotexist.bogus"))
+      fail "should have raised"
+    rescue => e
+      assert_includes e.message, "doesnotexist.bogus:80"
+    end
+  end
+
 end
 
 module TestNetHTTP_version_1_1_methods