bug#31495: 26.1; filename completion -vs- "*"

[Tom Tromey]

I found a situation where using "*" globbing in filename completion acts
strangely.

Here is how to set up to see the bug:

$ cd /tmp
$ mkdir -p a/b/c a/d/c
$ touch a/b/c/q

Now in Emacs, C-x C-f /tmp/a/*/c TAB

On the first TAB, a "/" is appended, and then point moves to the "/"
before "c".

Now type TAB again.
At this point, the "/tmp/a" is greyed out and the minibuffer shows:

Find file: /tmp/a//c/

... so now only completions for "/c" are available.

I think instead the "*" should be preserved.  Often I'm using this
feature to try to find a specific file where I don't know the exact
subdirectory it is in.





In GNU Emacs 26.1 (build 2, x86_64-pc-linux-gnu, GTK+ Version 3.22.26)
 of 2018-05-11 built on pokyo
Repository revision: c9c0e40d673a5fc0d24d30ff67ccb7c7f2fb482a
Windowing system distributor 'Fedora Project', version 11.0.11906000
System Description:     Fedora release 27 (Twenty Seven)

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Wrote /home/tromey/rust-debug.org
Saving file /home/tromey/rust-debug.org...
Wrote /home/tromey/rust-debug.org
Mark saved where search started [2 times]
Quit
Making completion list... [2 times]
Quit [3 times]
Invalid module name "flycheck_TestRustNames" [invalid-name] [2 times]

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