prePath middleware strips multiple slashes to an empty string

[mridgway]

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Restify Version: master
Node.js Version: 16.17.0

Expected behaviour

prePath middleware should reduce path /// to /.

Actual behaviour

prePath middleware reduces /// to `` (empty string).

Repro case

Test case: master...mridgway:node-restify:prePathEmptyString

Cause

This code will parse an empty string which returns null for pathname. The router will then assert the pathname as a string and throw.

Are you willing and able to fix this?

Yes, if/when I have some time.