go: net/url: first path segment in URL cannot contain colon.

Description：

No Scheme, and the address format is ”IP: Port“ Address parsing failed.

OS Ver: Mac OSX 10.12.3

Go Ver: 1.8

Go ENV:

GOARCH="amd64"
GOBIN=""
GOEXE=""
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GOOS="darwin"
GOPATH="/Users/shibingli/Develop/Go_Code/webconsole"
GORACE=""
GOROOT="/usr/local/go"
GOTOOLDIR="/usr/local/go/pkg/tool/darwin_amd64"
GCCGO="gccgo"
CC="clang"
GOGCCFLAGS="-fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/dy/lsbr_78131x3s9fjq15v8rg80000gn/T/go-build052845002=/tmp/go-build -gno-record-gcc-switches -fno-common"
CXX="clang++"
CGO_ENABLED="1"
PKG_CONFIG="pkg-config"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"

Code:

u, err := url.Parse("192.168.2.2:6688")
if nil != err {
       panic(err)
}
fmt.Println(u.Host, u.Port())

Error:

panic: parse 192.168.2.2:6688: first path segment in URL cannot contain colon

goroutine 1 [running]:
main.main()
	/Users/shibingli/Develop/Go_Code/webconsole/src/apibox.club/test/test.go:46 +0x138

Source:

https://github.com/golang/go/blob/release-branch.go1.8/src/net/url/url.go#L513