From c625bec2e5ddfbf2288555074f1cd14537b9832e Mon Sep 17 00:00:00 2001
From: Rob Browning <rlb@defaultvalue.org>
Date: Tue, 5 Nov 2013 16:29:53 -0600
Subject: [PATCH] Add current-filesystem and path-filesystems to t/lib.sh; use
 to guard test.

Add current-filesystem which reports the current filesystem type, and
path-filesystems which reports all the filesystems back up to the
root, and use the latter to skip the "save --strip-path (no match)"
test whenever all the filesystems involved aren't the same type.

This issue was discovered while testing on
/some/ext4/tree/containing/a/btrfs/tree.  When the test indexes/saves,
it picks up the metadata for the parents above the btrfs, which may
have (for example) linux +e attrs.  Then when it tries to restore the
tree fully within the btrfs, the restore defers an error when it tries
to restore the +e, which isn't valid for btrfs.

Normally we can avoid this problem via --strip, but this particular
test is actually checking the behavior when --strip doesn't apply.

Signed-off-by: Rob Browning <rlb@defaultvalue.org>
---
 t/lib.sh  | 23 ++++++++++++++++++++++-
 t/test.sh | 10 ++++++++++
 2 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/t/lib.sh b/t/lib.sh
index 4640379..c0a6278 100644
--- a/t/lib.sh
+++ b/t/lib.sh
@@ -1,4 +1,4 @@
-# Assumes shell is Bash.
+# Assumes shell is Bash, and pipefail is set.
 
 force-delete()
 {
@@ -35,3 +35,24 @@ realpath()
         "import sys, bup.helpers; print bup.helpers.realpath(sys.stdin.readline())" \
         || return $?
 }
+
+current-filesystem()
+{
+    df -T . | awk 'END{print $2}'
+}
+
+path-filesystems()
+(
+    # Return filesystem for each dir from $1 to /.
+    # Perhaps for /foo/bar, "ext4\next4\nbtrfs\n".
+    test "$#" -eq 1 || exit $?
+    cd "$1" || exit $?
+    current-filesystem || exit $?
+    dir="$(pwd)" || exit $?
+    while test "$dir" != /; do
+        cd .. || exit $?
+        dir="$(pwd)" || exit $?
+        current-filesystem || exit $?
+    done
+    exit 0
+)
diff --git a/t/test.sh b/t/test.sh
index 8cadb08..98b3ef3 100755
--- a/t/test.sh
+++ b/t/test.sh
@@ -459,6 +459,16 @@ WVSTART "save --strip-path (absolute)"
 
 WVSTART "save --strip-path (no match)"
 (
+    if test $(WVPASS path-filesystems . | WVPASS sort -u | WVPASS wc -l) -ne 1
+    then
+        # Skip the test because the attempt to restore parent dirs to
+        # the current filesystem may fail -- i.e. running from
+        # /foo/ext4/bar/btrfs will fail when bup tries to restore
+        # linux attrs above btrfs to the restore tree *inside* btrfs.
+        echo "(running from tree with mixed filesystems; skipping test)" 1>&2
+        exit 0
+    fi
+
     tmp=graft-points.tmp
     WVPASS force-delete $tmp
     WVPASS mkdir $tmp
-- 
2.39.2