Add and use a DOCKER prereq

License: MIT
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>

test/sharness/lib/test-lib.sh

@@ -41,6 +41,7 @@ SHARNESS_LIB="lib/sharness/sharness.sh"
 # grab + output options
 test "$TEST_NO_FUSE" != 1 && test_set_prereq FUSE
 test "$TEST_EXPENSIVE" = 1 && test_set_prereq EXPENSIVE
+type docker && test_set_prereq DOCKER
 
 if test "$TEST_VERBOSE" = 1; then
 	echo '# TEST_VERBOSE='"$TEST_VERBOSE"

test/sharness/t0300-docker-image.sh

@@ -8,9 +8,12 @@ test_description="Test docker image"
 
 . lib/test-lib.sh
 
-test_expect_success "docker is installed" '
-	type docker
-'
+# if in travis CI on OSX, docker is not available
+if ! test_have_prereq DOCKER; then
+	skip_all='skipping docker tests, docker not available'
+
+	test_done
+fi
 
 test_expect_success "'docker --version' works" '
 	docker --version >actual