Avoid non-standard escape sequences in tr command

[michaelforney]

POSIX says

The -escape sequences in Escape Sequences and Associated Actions ( '\', '\a', '\b', '\f', '\n', '\r', '\t', '\v' ) shall be supported. The results of using any other character, other than an octal digit, following the are unspecified. Also, if there is no character following the , the results are unspecified.

Instead, just use -- to separate options and operands, since tr(1)
is required to conform to the Utility Syntax Guidelines.

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @alexcrichton (or someone else) soon.

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[michaelforney]

Alternatively, the two tr invocations could be replaced with tr 'a-z-' 'A-Z_', which seems to be how it is done elsewhere in the file.

[michaelforney]

@alexcrichton Ping. If you have a minute, could take a quick look at this?

Alternatively, the two tr invocations could be replaced with tr 'a-z-' 'A-Z_', which seems to be how it is done elsewhere in the file.

I pushed a new commit that does this.

[alexcrichton]

Thanks for the PR here, but unfortunately I don't have the time to help shepherd this change through. This is a pretty ossified script at this point and it would require much more energy than I have available to change it. Others may be interested in helping out with review though!

[Mark-Simulacrum]

The changes here look good. I'm not sure they'll hold up with Unicode input, but I'm guessing that's already the case today.

@bors r+