[Downloader] Print underlying error in HTTPError

lib/bundler/fetcher/downloader.rb

@@ -58,9 +58,10 @@ def request(uri, options)
         case e.message
         when /host down:/, /getaddrinfo: nodename nor servname provided/
           raise NetworkDownError, "Could not reach host #{uri.host}. Check your network " \
-          "connection and try again."
+            "connection and try again."
         else
-          raise HTTPError, "Network error while fetching #{URICredentialsFilter.credential_filtered_uri(uri)}"
+          raise HTTPError, "Network error while fetching #{URICredentialsFilter.credential_filtered_uri(uri)}" \
+            " (#{e})"
         end
       end
 

spec/bundler/fetcher/downloader_spec.rb

@@ -222,7 +222,7 @@
 
         it "should raise a Bundler::HTTPError" do
           expect { subject.request(uri, options) }.to raise_error(Bundler::HTTPError,
-            "Network error while fetching http://www.uri-to-fetch.com/api/v2/endpoint")
+            "Network error while fetching http://www.uri-to-fetch.com/api/v2/endpoint (other error about network)")
         end
 
         context "when the there are credentials provided in the request" do
@@ -233,7 +233,7 @@
 
           it "should raise a Bundler::HTTPError that doesn't contain the password" do
             expect { subject.request(uri, options) }.to raise_error(Bundler::HTTPError,
-              "Network error while fetching http://username@www.uri-to-fetch.com/api/v2/endpoint")
+              "Network error while fetching http://username@www.uri-to-fetch.com/api/v2/endpoint (other error about network)")
           end
         end
       end
@@ -243,7 +243,7 @@
 
         it "should raise a Bundler::Fetcher::HTTPError" do
           expect { subject.request(uri, options) }.to raise_error(Bundler::HTTPError,
-            "Network error while fetching http://www.uri-to-fetch.com/api/v2/endpoint")
+            "Network error while fetching http://www.uri-to-fetch.com/api/v2/endpoint (#{message})")
         end
       end
     end