http/httpproxy: document all loopbacks are special cased not just localhost
Fixes golang/go#33695
Change-Id: I2f7598da7c6fda161ba357a75bba72de2fee8226
GitHub-Last-Rev: 443dbb13b1dc9ec275cdb796caf31dd3b6b658c3
GitHub-Pull-Request: golang/net#116
Reviewed-on: https://go-review.googlesource.com/c/net/+/356510
Reviewed-by: Damien Neil <dneil@google.com>
Trust: Damien Neil <dneil@google.com>
Trust: Cherry Mui <cherryyz@google.com>
Run-TryBot: Damien Neil <dneil@google.com>
diff --git a/http/httpproxy/proxy.go b/http/httpproxy/proxy.go
index 1415b07..d2c8c87 100644
--- a/http/httpproxy/proxy.go
+++ b/http/httpproxy/proxy.go
@@ -113,8 +113,8 @@
// environment, or a proxy should not be used for the given request, as
// defined by NO_PROXY.
//
-// As a special case, if req.URL.Host is "localhost" (with or without a
-// port number), then a nil URL and nil error will be returned.
+// As a special case, if req.URL.Host is "localhost" or a loopback address
+// (with or without a port number), then a nil URL and nil error will be returned.
func (cfg *Config) ProxyFunc() func(reqURL *url.URL) (*url.URL, error) {
// Preprocess the Config settings for more efficient evaluation.
cfg1 := &config{
