Rust Programming

Well, as it says in the documentation I linked:

unlike canonicalize absolute does not resolve symlinks and may succeed even if the path does not exist.

Primarily, the latter part is what I want. There's just sometimes situations where a path doesn't exist (yet), but you want to know what it would look like as an absolute path.

It still returns relative paths if the input was relative

False

and it doesn’t resolve “…”

I'll assume you meant .., since ... is an ordinary filename. (Aside from the "who remembers ...?" feature introduced in Windows 95's COMMAND.COM where cd ... was shorthand for doing cd .. twice and you could omit the space after cd if your target was all dots.)

The reason it doesn't do that is that, when symlinks get involved, /foo/bar/.. does not necessarily resolve to /foo and making that assumption could introduce a lurking security vulnerability in programs which use it.