[PATCH v2] tests/check-block: Do not run the iotests with old versions of bash

[Thomas Huth <thuth@redhat.com>]

macOS is shipped with a very old version of the bash (3.2), which
is currently not suitable for running the iotests anymore (e.g.
it is missing support for "readarray" which is used in the file
tests/qemu-iotests/common.filter). Add a check to skip the iotests
in this case - if someone still wants to run the iotests on macOS,
they can install a newer version from homebrew, for example.

Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 v2: Use LANG=C and "-q"

 tests/check-block.sh | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/tests/check-block.sh b/tests/check-block.sh
index a5a69060e1..f6b1bda7b9 100755
--- a/tests/check-block.sh
+++ b/tests/check-block.sh
@@ -46,6 +46,11 @@ if ! command -v bash >/dev/null 2>&1 ; then
     exit 0
 fi
 
+if LANG=C bash --version | grep -q 'GNU bash, version [123]' ; then
+    echo "bash version too old ==> Not running the qemu-iotests."
+    exit 0
+fi
+
 if ! (sed --version | grep 'GNU sed') > /dev/null 2>&1 ; then
     if ! command -v gsed >/dev/null 2>&1; then
         echo "GNU sed not available ==> Not running the qemu-iotests."
-- 
2.18.2