Use pushd and popd for ci/tests.sh

ci/tests.sh

@@ -12,8 +12,9 @@ function test_fluentd_plugin() {
   local version="${2}"
   # Strip everything after "-" (longest match) to avoid gem prerelease behavior
   local gem_version="${version%%-*}"
+  local result
 
-  cd "${plugin_name}" || exit 1
+  pushd "${plugin_name}" || exit 1
 
   if [[ -z "${version}" ]] ; then
     echo "Please provide the version when bundling fluentd plugins"
@@ -28,7 +29,13 @@ function test_fluentd_plugin() {
   bundle install
 
   echo "Run unit tests..."
-  bundle exec rake || exit 1
+  bundle exec rake
+
+  readonly result=$?
+  popd || exit 1
+  if [ "${result}" -eq "0" ]; then
+   exit 1
+  fi
 }
 
 function test_fluentd_plugins() {
@@ -42,7 +49,7 @@ function test_fluentd_plugins() {
   find . -maxdepth 1 -name 'fluent-plugin-*' -type 'd' -print |
     while read -r line; do
       # Run tests in their own context
-      (test_fluentd_plugin "$(basename "${line}")" "${version}") || exit 1
+      test_fluentd_plugin "$(basename "${line}")" "${version}" || exit 1
     done
 }