Bug 1534500 - Allow diffoscope tasks to work on unpacked builds. r=dustin

Depends on D23073

Differential Revision: https://phabricator.services.mozilla.com/D23074

--HG--
extra : moz-landing-system : lando

taskcluster/docker/diffoscope/get_and_diffoscope

@@ -48,6 +48,15 @@ case "$ORIG_URL" in
 	;;
 esac
 
+case "$ORIG_URL" in
+*/target.apk)
+	OMNIJAR=assets/omni.ja
+	;;
+*)
+	OMNIJAR=omni.ja
+	;;
+esac
+
 # Builds are 99% of the time differing in some small ways, so it's not
 # really useful to report a failure (at least not until we actually
 # care about the builds being 100% identical).
@@ -55,6 +64,14 @@ POST=true
 
 for option; do
 	case "$option" in
+	--unpack)
+		CURDIR=$PWD
+		for dir in a b; do
+			# Need to run mach python from inside the gecko source.
+			# See bug #1533642.
+			(cd $GECKO_PATH && ./mach python toolkit/mozapps/installer/unpack.py --omnijar $OMNIJAR $CURDIR/$dir)
+		done
+		;;
 	--fail)
 		POST="exit 1"
 		;;

taskcluster/taskgraph/transforms/diffoscope.py

@@ -47,6 +47,11 @@ diff_description_schema = Schema({
 
     # Fail the task when differences are detected.
     Optional('fail-on-diff'): bool,
+
+    # Whether to unpack first. Diffoscope can normally work without unpacking,
+    # but when one needs to --exclude some contents, that doesn't work out well
+    # if said content is packed (e.g. in omni.ja).
+    Optional('unpack'): bool,
 })
 
 transforms = TransformSequence()
@@ -139,8 +144,9 @@ def fill_template(config, tasks):
             },
             'run': {
                 'using': 'run-task',
-                'checkout': False,
-                'command': '/builds/worker/bin/get_and_diffoscope{}'.format(
+                'checkout': task.get('unpack', False),
+                'command': '/builds/worker/bin/get_and_diffoscope{}{}'.format(
+                    ' --unpack' if task.get('unpack') else '',
                     ' --fail' if task.get('fail-on-diff') else '',
                 ),
             },