minimal conversion to perl / debhelper lib

It turns out this isn't $MESSY_CONFLICT_ZONE, there are rules about
writing debhelper extensions.

This is mainly cargo culting from dh_installdocs.

- compute destination directory, support multiple binary packages.

- add debian/elpa file, test the "standard" codepath. Still not very
  standard because it's a single file elpa package.

1 files changed, 32 insertions, 5 deletions

diff --git a/dh_elpa b/dh_elpa
index d867c47..c122f48 100755
--- a/dh_elpa
+++ b/dh_elpa
@@ -1,6 +1,33 @@
-#!/bin/sh
+#!/usr/bin/perl
 
-emacs -batch -Q  -l package \
-      --eval '(add-to-list (quote package-directory-list) "/usr/share/emacs/site-lisp/elpa")' \
-      -f package-initialize \
-      -l dh-elpa.el -f dhelpa-batch-install-file "$@"
+use Debian::Debhelper::Dh_Lib;
+
+init();
+
+my $elpadir="/usr/share/emacs/site-lisp/elpa";
+
+foreach my $package (@{$dh{DOPACKAGES}}) {
+
+  my $tmp=tmpdir($package);
+  my $file=pkgfile($package,"elpa");
+
+  my @files;
+  if ($file) {
+    @files=filearray($file, ".");
+  }
+  if (($package eq $dh{FIRSTPACKAGE} || $dh{PARAMS_ALL})
+      && @ARGV) {
+    push @files, @ARGV;
+  }
+
+  if (scalar(@files) == 1) {
+    $pkg_file=$files[0];
+  } else {
+    die("multifile packages unimplimented");
+  }
+
+  doit(qw{emacs -batch -Q -l package},
+       '--eval',"(add-to-list 'package-directory-list \"$elpadir\")",
+       qw{-f package-initialize -l dh-elpa.el},
+       qw{-f dhelpa-batch-install-file}, "$tmp/$elpadir", $pkg_file);
+}