NAMESTRING of tilde + directory that doesn't exist doesn't expand the tilde

[Vinced]

I was expecting that (namestring "~/nothinghere"), a tilde with a directory name that doesn't exist locally, would expand to "/home/user/nothinghere", but it just leaves the tilde.

In CLisp and CCL, the tilde is expanded.

Same for PATHNAME.

This point is mentioned in https://bugs.launchpad.net/sbcl/+bug/1790330.

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SBCL 1.4.5.debian

Linux 5.0.0-31-generic #33~18.04.1-Ubuntu SMP Tue Oct 1 10:20:39 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

*features*
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 :SB-BSD-SOCKETS-ADDRINFO :ASDF3.3 :ASDF3.2 :ASDF3.1 :ASDF3 :ASDF2 :ASDF
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[Stas Boukarev (stassats)]

namestring doesn't expand any ~, existing or not.

[Vinced (vincezd)]

Damn right. I'd find great if it did, as in some other implementations.

truename doesn't, but that is expected, well documented, and consistent with other implementations.

[Stas Boukarev (stassats)]

CCL doesn't expand in namestring either, it does it before the pathname is constructed.