See the Slack discussion for more context and motivation for this change.

Schemes (e.g. "dir", "docker") should be delimited from the rest of the URI by a colon (:), not by a colon and two slashes (://). (It's okay if an individual scheme requires two slashes to begin the scheme-specific portion of the URI.)

For example, if users want to scan the current directory, then instead of typing:

$ syft dir://.

Users would type:

$ syft dir:.

In addition, if we can detect that an input string that lacks a scheme specification (e.g. no dir:) is most likely to be a filesystem path as opposed to another specification, we could allow an even easier syntax for an implicit specification of input source:

$ syft .