perf/aggregate: add display_dir()

diff --git a/t/test-lib.sh b/t/test-lib.sh
index 9535d2e0a936eb1b7a84686a9b702d3ca9fd680d..7740d511d289f44bb1313308fe49d5894f64b3c2 100644 (file)
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -264,7 +264,24 @@ do
                GIT_TEST_CHAIN_LINT=0
                shift ;;
        -x)
-               trace=t
+               # Some test scripts can't be reliably traced  with '-x',
+               # unless the test is run with a Bash version supporting
+               # BASH_XTRACEFD (introduced in Bash v4.1).  Check whether
+               # this test is marked as such, and ignore '-x' if it
+               # isn't executed with a suitable Bash version.
+               if test -z "$test_untraceable" || {
+                    test -n "$BASH_VERSION" && {
+                      test ${BASH_VERSINFO[0]} -gt 4 || {
+                        test ${BASH_VERSINFO[0]} -eq 4 &&
+                        test ${BASH_VERSINFO[1]} -ge 1
+                      }
+                    }
+                  }
+               then
+                       trace=t
+               else
+                       echo >&2 "warning: ignoring -x; '$0' is untraceable without BASH_XTRACEFD"
+               fi
                shift ;;
        --verbose-log)
                verbose_log=t