Add basic docker-dind test

test/config.sh

@@ -33,6 +33,9 @@ declare -A imageTests=(
 	[debian]='
 		debian-apt-get
 	'
+	[docker:dind]='
+		docker-dind
+	'
 	[django]='
 	'
 	[elasticsearch]='

test/tests/docker-dind/run.sh

@@ -0,0 +1,45 @@
+#!/bin/bash
+set -e
+
+image="$1"
+
+cname="docker-daemon-container-$RANDOM-$RANDOM"
+cid="$(
+	docker run -d -it \
+		--privileged \
+		--name "$cname" \
+		"$image"
+)"
+trap "docker rm -vf $cid > /dev/null" EXIT
+
+docker_() {
+	docker run --rm -i \
+		--link "$cname":docker \
+		--entrypoint docker-entrypoint.sh \
+		"$image" \
+		"$@"
+}
+
+tries=10
+while ! docker_ version &> /dev/null; do
+	(( tries-- ))
+	if [ $tries -le 0 ]; then
+		echo >&2 'docker daemon failed to accept connections in a reasonable amount of time!'
+		( set -x && docker logs "$cid" ) >&2 || true
+		docker_ version # to hopefully get a useful error message
+		false
+	fi
+	sleep 2
+done
+
+docker_ pull busybox
+
+docker_ run --rm busybox true
+
+docker_ create -i --name test busybox cat
+[ "$(docker_ inspect -f '{{.State.Running}}' test)" = 'false' ]
+docker_ start test
+[ "$(docker_ inspect -f '{{.State.Running}}' test)" = 'true' ]
+docker_ stop test
+[ "$(docker_ inspect -f '{{.State.Running}}' test)" = 'false' ]
+docker_ rm test