Question: Why are Windows local device paths not supported?

I noticed the following behaviour in the unit tests:

// Paths starting with "\\.\" (Local Device Paths) are intentionally not supported.
let url = Url::from_file_path(Path::new(r"\\.\some\path\file.txt"));
assert!(url.is_err());

However, I can't find any discussion of this in the PR (#360) or its predecessor (#284). Why are they not supported?

I don't actually have a need for this to change; I'm just trying to survey the behaviour of URL libraries and applications. Since there is an actual test for this with an explicit comment, I expect that support was considered but deemed unsuitable for some reason?

Additionally, I noticed that the reverse is not true - this library will take a URL like file://./some/path/file.txt and turn it in to a local device path (\\.\some\path\file.txt). You may need to explicitly set the host to ".", as IIRC Url::parse stripped it for some reason.

I realise that the PR which introduced this is 5 years old, so perhaps nobody remembers the reason. Still, any information you do remember would be much appreciated. Thanks!

Start with the Windows path test in url/tests/unit.rs around line 745, then review PRs #360 and #284 for the historical rationale. Compare the stated behavior with the reverse conversion described in the issue; done means confirming the reason for the limitation and recording a clear explanation.