Bug#826751: apt: download even not on AC power

[Sanjoy Mahajan <sanjoy@olin.edu>]

Package: apt
Version: 1.2.12
Severity: wishlist
File: /usr/lib/apt/apt.systemd.daily

Dear Maintainer,

On my last laptop, I appreciated the forbearance of the daily apt cron
run, which exited on battery power.  This laptop fortunately has an SSD,
and the apt run doesn't produce much battery drain.

Thus, could the apt.systemd.daily script incorporate an option like
"DownloadEvenOnBatteryPower" (false by default)?  For now, I comment out
the two checks as shown in the following diff.  But whenever the script
is updated upstream, I lose my change.

--- /usr/lib/apt/apt.systemd.daily	2016-05-11 10:48:22.000000000 -0400
+++ /usr/lib/apt/apt.systemd.daily	2016-06-08 11:29:04.117437843 -0400
@@ -357,7 +357,7 @@
     set -x
 fi
 
-check_power || exit 0
+# check_power || exit 0
 
 # check if we can lock the cache and if the cache is clean
 if which apt-get >/dev/null 2>&1 && ! eval apt-get check $XAPTOPT $XSTDERR ; then
@@ -410,7 +410,7 @@
 do_cache_backup $BackupArchiveInterval
 
 # ensure we don't do this on battery
-check_power || exit 0
+# check_power || exit 0
 
 # include default system language so that "apt-get update" will
 # fetch the right translated package descriptions


-- System Information:
Debian Release: stretch/sid
  APT prefers testing
  APT policy: (990, 'testing'), (500, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.5.0-2-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.utf8, LC_CTYPE=en_US.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages apt depends on:
ii  adduser                 3.114
ii  debian-archive-keyring  2014.3
ii  gnupg                   1.4.20-6
ii  gnupg2                  2.1.11-7
ii  gpgv                    1.4.20-6
ii  init-system-helpers     1.34
ii  libapt-pkg5.0           1.2.12
ii  libc6                   2.22-9
ii  libgcc1                 1:6.1.1-4
ii  libstdc++6              6.1.1-4

apt recommends no packages.

Versions of packages apt suggests:
pn  apt-doc     <none>
ii  aptitude    0.7.5-3
ii  dpkg-dev    1.18.7
ii  python-apt  1.1.0~beta2
ii  synaptic    0.83+b1

-- no debconf information

-- debsums errors found:
debsums: changed file /usr/lib/apt/apt.systemd.daily (from apt package)