Bug#864143: initramfs-tools: missing dependency on busybox?

[Dave Love <dave.love@manchester.ac.uk>]

Package: initramfs-tools
Version: 0.130
Severity: normal

Dear Maintainer,

initramfs-tools-core recommends busybox, but it appears to be required.
I got this with an update after it was removed:
  
  Processing triggers for initramfs-tools (0.130) ...
  update-initramfs: Generating /boot/initrd.img-4.9.0-3-amd64
  E: busybox or busybox-static, version 1:1.22.0-17~ or later, is required but not installed
  update-initramfs: failed for /boot/initrd.img-4.9.0-3-amd64 with 1.
  dpkg: error processing package initramfs-tools (--configure):
   subprocess installed post-installation script returned error exit status 1
  Errors were encountered while processing:
   initramfs-tools

-- Package-specific info:

[trimmed]

-- /etc/initramfs-tools/modules

-- /etc/kernel-img.conf
# Kernel image management overrides
# See kernel-img.conf(5) for details
do_symlinks = yes
do_bootloader = no
do_initrd = yes
link_in_boot = no

-- /etc/initramfs-tools/initramfs.conf
MODULES=most
BUSYBOX=auto
KEYMAP=n
COMPRESS=gzip
DEVICE=
NFSROOT=auto

-- /etc/initramfs-tools/update-initramfs.conf
update_initramfs=yes
backup_initramfs=no

-- /etc/crypttab
sdb5_crypt UUID=d9323359-0041-4e58-924d-bf85d798f8a8 none luks

-- mkinitramfs hooks
/etc/initramfs-tools/hooks/:

/usr/share/initramfs-tools/hooks:
cryptgnupg
cryptkeyctl
cryptopenct
cryptopensc
cryptpassdev
cryptroot
cryptroot-unlock
dmsetup
fsck
fuse
keymap
klibc-utils
kmod
lvm2
resume
thermal
udev


-- System Information:
Debian Release: 9.0
  APT prefers testing-debug
  APT policy: (500, 'testing-debug'), (500, 'testing')
Architecture: amd64 (x86_64)

Kernel: Linux 4.9.0-2-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_GB.utf8, LC_CTYPE=en_GB.utf8 (charmap=UTF-8), LANGUAGE=en_GB:en (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: sysvinit (via /sbin/init)

Versions of packages initramfs-tools depends on:
ii  initramfs-tools-core  0.130
ii  linux-base            4.5

initramfs-tools recommends no packages.

Versions of packages initramfs-tools suggests:
ii  bash-completion  1:2.1-4.3

-- no debconf information