Prepare rred binary for external usage

Merging patches is a bit of non-trivial code we have for client-side
work, but as we support also server-side merging we can export this
functionality so that server software can reuse it.

Note that this just cleans up and makes rred behave a bit more like all
our other binaries by supporting setting configuration at runtime and
supporting --help and --version. If you can make due without this, the
now advertised functionality is provided already in earlier versions.

2 files changed, 42 insertions, 1 deletions

diff --git a/test/integration/test-00-commands-have-help b/test/integration/test-00-commands-have-help
index 4a0cc64d4..f91238d5d 100755
--- a/test/integration/test-00-commands-have-help
+++ b/test/integration/test-00-commands-have-help
@@ -49,7 +49,11 @@ for CMD in 'apt-cache' 'apt-cdrom' 'apt-config' \
 	checkoptions "$cmd"
 done
 
-for CMD in 'apt-dump-solver'  'apt-internal-solver' 'apt-internal-planner'; do
+
+rred() {
+	runapt "${METHODSDIR}/rred" "$@"
+}
+for CMD in 'apt-dump-solver'  'apt-internal-solver' 'apt-internal-planner' 'rred'; do
 	checkoptions "$(echo "$CMD" | tr -d '-')"
 done
 
diff --git a/test/integration/test-method-rred b/test/integration/test-method-rred
index 5a885e9d2..00b4b7c0b 100755
--- a/test/integration/test-method-rred
+++ b/test/integration/test-method-rred
@@ -195,3 +195,40 @@ Package: supercoolstuff
 failrred 'Wrong order of commands' '7d
 17d'
 failrred 'End before start' '7,6d'
+
+# deal correctly with patch merging
+mergepatches() {
+	testsuccess runapt "${METHODSDIR}/rred" Packages.ed-*
+	cp -a rootdir/tmp/testsuccess.output patch.ed
+	testfileequal 'patch.ed' "$1"
+}
+createpatch() {
+	echo "$2"
+}
+
+createpatch 'Change dog to cat + kitties' '19c
+ And a cat!
+
+Package: extra-kittens
+Version: unavailable
+Description: fix later
+.' > Packages.ed-0
+createpatch 'Remove more stuff and fix later' '23d,
+6d' > Packages.ed-1
+createpatch 'Remove (old) dog paragraph' '10,19d' > Packages.ed-2
+mergepatches '11,19c
+Package: extra-kittens
+Version: unavailable
+.
+6d'
+testrred 'Apply' 'merged patch' "$(cat patch.ed)" 'Package: coolstuff
+Version: 0.8.15
+Description: collection of stuff
+ A lot, too much to iterate all, but at least this:
+ - stuff
+ - even more stuff
+ .
+ And a cow.
+
+Package: extra-kittens
+Version: unavailable'