Improve makeValid/isValid further (on windows)

[hasufell]

hasufell/abstract-filepath#10 (comment)

But as an example the file you linked makes an assumption that the only valid absolute filepath on Windows is one that starts with a drive letter. Which is not true.

It also makes an assumption that badElements is invalid for all paths on Windows. Which is also not true. e.g. \.\COM1 is perfectly valid and points to the first COM port.

It makes an attempt to distinguish between the different namespaces. As in, it recognizes \?\ but then makeValid doesn't seem to.

Also related: #56

[hasufell]

@Mistuke

[hasufell]

I also noticed this, which I find confusing:

splitDrive "\\\\?\\UNCshared\\file" == ("\\\\?\\","UNCshared\\file")

"\\\\?\\" isn't really a drive... is it?

[Mistuke]

No, technically speaking that path has no drive, but... Is also invalid.

I'm assuming it was supposed to be "\\\\?\\UNC\\shared\\file" since the UNC is required to indicate it's a UNC path.

Not all Paths in Windows have a drive.

"\\?\" isn't really a drive... is it?

Indeed, \\?\ is a marker to tell the win32 api to not process the path but instead send it straight through to the fs driver.

It's in the so called Win32 “namespace". There are other namespaces like the device on \\.\.

Note that because these skip processing from the API layer that you the paths can't contain OS level concept like . and ..

[hasufell]

@Mistuke I just implemented the lexer that Neil was aiming at, which might make a lot of the internals easier and more robust. Please check out my comment here: #53 (comment)

There's likely stuff missing or incorrect, but I think it's a good start.