absoluteTo() doesn't work with file:/// ?

[CXuesong]

As far as I know, I can make an absolute URL using the following routine

var rel = new URI("http://example.org/abc");    // Well, not so relative, but I believe it will still works.
rel.absoluteTo("https://abc.xyz/def").toString();

which results in

"http://example.org/abc"

It works fine.

However, when I want to use absoluteTo with file:/// protocol, like this

var rel = new URI("file:///D:/file.txt");
rel.absoluteTo("https://abc.xyz/def").toString();

I get

"https://abc.xyz/D:/file.txt"

instead of

file:///D:/file.txt

Is this a bug, or have I got this wrong? Thank you!

[rodneyrehm]

The issue is not triggered by or limited to the file:// protocol.

If alpha is a fully qualified URL alpha.absoluteTo(bravo) simply returns alpha:

var rel = new URI("a://b/c?d#e");
rel.absoluteTo("v://w/x?y#z").toString();
// "a://b/c?d#e"

if alpha does not contain an authority alpha.absoluteTo(bravo) simply returns the authority of bravo and the resource of alpha:

var rel = new URI("a:///c?d#e");
rel.absoluteTo("v://w/x?y#z").toString();
// "v://w/c?d#e"

RFC 3986 - 5.2 Relative Resolution explains the algorithm to do this. However, it clearly states that if there is a scheme, the authority of the resolving URL should be used. URI.js on the other hand does a simple merge of all components. This behavior was introduced with a fix for #73 nearly 4 years ago. Given how long this behavior has been in place and you being the first one to stumble over it, I'm wondering if reverting to strict RFC 3986 compliance is the best course of action…

[CXuesong]

Thank you for your explanation! I've also taken a look at #158 , and if I got this right, because the authority of some alpha like file:/// is empty, it will be replaced with the authority of bravo according to your reply.

I've to say, this is really a rare case. At least in my situation, I hardly had a chance to process file:///, and if I were to handle such case, I will just check whether the protocol is file:// first. After all, there won't be such a URL like http:///abc.

[rodneyrehm]

After all, there won't be such a URL like http:///abc.

I've never seen that in the wild. It doesn't mean it doesn't exist, but I consider it much less likely than file:///. This would lead to the conclusion that the resolved URI may only contain bravo's authority if alpha does not contain a scheme.

Do you want to create a patch for this?

[CXuesong]

Oh, it's a pleasure! Give me a moment ;-)

[rodneyrehm]

thank you! released as v1.18.8