Weird behavior of 'ash' with "remove prefix/suffix pattern" in parameter expansion

[walter harms]

Am 24.11.2016 09:28, schrieb Denys Vlasenko:
> ./busybox ash -c 'TEST="[[[[" ; echo "${TEST#[}"'

wired ...

./busybox ash -c 'TEST="[[[[" ; echo "${TEST#[}"'
[[[[

./busybox --help
BusyBox v1.25.0 (2016-11-22 18:02:23 CET) multi-call binary.
BusyBox is copyrighted by many authors between 1998-2015.
Licensed under GPLv2. See source distribution for detailed
copyright notices.

Usage: busybox [function [arguments]...]
   or: busybox --list[-full]
   or: busybox --install [-s] [DIR]
   or: function [arguments]...

        BusyBox is a multi-call binary that combines many common Unix
        utilities into a single executable.  Most people will create a
        link to busybox for each function they wish to use and BusyBox
        will act like whatever it was invoked as.

Currently defined functions:
        ash, bunzip2, bzcat, bzip2, chpasswd, cpio, gunzip, gzip, lzcat, lzma,
        lzop, lzopcat, rpm, rpm2cpio, sh, tar, unlzma, unlzop, unxz, unzip,
        whoami, xz, xzcat, zcat


I have attached my .config.

re,
 wh
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