tests: Use skip_without_ostree_feature to detect libarchive, composefs

This avoids false negatives from `ostree --version | grep -q ...`
exiting with failure under `set -o pipefail` because `grep -q` can exit
as soon as it sees the desired string, leaving `ostree --version` to be
terminated by `SIGPIPE` next time it writes to stdout.

Signed-off-by: Simon McVittie <[email protected]>
Forwarded: ostreedev/ostree#3184

Gbp-Pq: Name tests-Use-skip_without_ostree_feature-to-detect-libarchiv.patch

tests/test-composefs.sh

@@ -19,11 +19,7 @@ set -euo pipefail
 
 . $(dirname $0)/libtest.sh
 
-if ! ${CMD_PREFIX} ostree --version | grep -q -e '- composefs'; then
-    echo "1..0 #SKIP no composefs support compiled in"
-    exit 0
-fi
-
+skip_without_ostree_feature composefs
 skip_without_user_xattrs
 
 setup_test_repository "bare-user"

tests/test-export.sh

@@ -19,13 +19,9 @@
 
 set -euo pipefail
 
-if ! ostree --version | grep -q -e '- libarchive'; then
-    echo "1..0 #SKIP no libarchive support compiled in"
-    exit 0
-fi
-
 . $(dirname $0)/libtest.sh
 
+skip_without_ostree_feature libarchive
 setup_test_repository "archive"
 
 echo '1..6'

tests/test-libarchive.sh

@@ -19,13 +19,10 @@
 
 set -euo pipefail
 
-if ! ostree --version | grep -q -e '- libarchive'; then
-    echo "1..0 #SKIP no libarchive support compiled in"
-    exit 0
-fi
-
 . $(dirname $0)/libtest.sh
 
+skip_without_ostree_feature libarchive
+
 echo "1..18"
 
 setup_test_repository "bare"