:Rename does not escape characters in the directory path

[Mange]

Test case:

mkdir \$dollar.bill && touch \$dollar.bill/foo
nvim \$dollar.bill/foo

:Rename bar

Expected:

$dollar.bill/foo is renamed to $dollar.bill/bar and the buffer is opened.

Actual:

$dollar.bill/foo is renamed to .bill/bar since $dollar was treated like an environment variable.

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NOTE: The prompted filename is escaped properly, i.e. renaming a foo to a $bar works. This only happens inside the directory prefix.

[Mange]

Thanks! ❤️