Subject: [PATCH v3 6/8] test-lib: extract Bash version check for '-x' tracing

From: SZEDER Gábor <[email-masked]>
Date: Sun, 30 Dec 2018 20:16:27 +0100

One of our test scripts, 't1510-repo-setup.sh' [1], still can't be
reliably run with '-x' tracing enabled, unless it's executed with a
Bash version supporting BASH_XTRACEFD (since v4.1).  We have a lengthy
condition to check the version of the shell running the test script,
and disable tracing if it's not executed with a suitable Bash version
[2].

Move this check out from the option parsing loop, so other options can
imply '-x' by setting 'trace=t', without missing this Bash version
check.

[1] 5827506928 (t1510-repo-setup: mark as untraceable with '-x',
    2018-02-24)
[2] 5fc98e79fc (t: add means to disable '-x' tracing for individual
    test scripts, 2018-02-24)

Signed-off-by: SZEDER Gábor <[email-masked]>
---
 t/test-lib.sh | 38 +++++++++++++++++++-------------------
 1 file changed, 19 insertions(+), 19 deletions(-)

diff --git a/t/test-lib.sh b/t/test-lib.sh
index 2b88ba2de1..7d77a26d44 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -134,25 +134,7 @@ do
 	--no-chain-lint)
 		GIT_TEST_CHAIN_LINT=0 ;;
 	-x)
-		# 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; '$0' is untraceable without BASH_XTRACEFD"
-		fi
-		;;
+		trace=t ;;
 	-V|--verbose-log)
 		verbose_log=t
 		tee=t
@@ -178,6 +160,24 @@ then
 	test -z "$verbose_log" && verbose=t
 fi
 
+if test -n "$trace" && test -n "$test_untraceable"
+then
+	# '-x' tracing requested, but this test script can't be reliably
+	# traced, unless it is run with a Bash version supporting
+	# BASH_XTRACEFD (introduced in Bash v4.1).
+	if test -n "$BASH_VERSION" && {
+	     test ${BASH_VERSINFO[0]} -gt 4 || {
+	       test ${BASH_VERSINFO[0]} -eq 4 &&
+	       test ${BASH_VERSINFO[1]} -ge 1
+	     }
+	   }
+	then
+		: Executed by a Bash version supporting BASH_XTRACEFD.  Good.
+	else
+		echo >&2 "warning: ignoring -x; '$0' is untraceable without BASH_XTRACEFD"
+		trace=
+	fi
+fi
 if test -n "$trace" && test -z "$verbose_log"
 then
 	verbose=t
-- 
2.20.1.151.gec613c4b75