net/url: add URL.ForceFragment like ForceQuery for empty fragments to stringify with '#' #29603
Closed as not planned
Description
What version of Go are you using (go version)?
go version go1.11.2 linux/amd64
What did you do?
import (
"fmt"
"log"
"net/url"
)
func main() {
u, err := url.Parse("http://example.com/#")
if err != nil {
log.Fatal(err)
}
fmt.Println(u.String())
fmt.Println(u.Fragment)
}What did you expect to see?
http://example.com/#
#
What did you see instead?
http://example.com/
What's the issue?
At first glance, http://example.com/# and http://example.com/ are logically the same URL. This is largely true in the context of a browser navigating to that URL as typed into the URL bar, but they are subtly different in a link. If a user clicks the following link:
<a href="http://example.com/#">foo</a>If the document URL (or <base href>) is http://example.com/ then this click does not cause a navigation - it is a within document link. However, if the link was instead to:
<a href="http://example.com/">foo</a>Then clicking it causes a navigation. A reload really, but still a navigation.
This becomes more of an issue when net/url is used to resolve a relative URL:
<html>
<head>
<base href="http://example.com/">
</head>
<body>
<a href="/">reload</a>
<a href="#">inert</a>
</body>
</html>base, _ = url.Parse("http://example.com/")
nav, _ = base.Parse("/")
local, _ = base.Parse("#")nav and local are now equal, which means it's not possible to distinguish a document local link and a navigation link.