test-lib: valgrind for only tests matching a pattern

With the new --valgrind-only=<pattern> option, one can enable
--valgrind at a per-test granularity, exactly analogous to
--verbose-only from the previous commit.

The options are wired such that --valgrind implies --verbose (as
before), but --valgrind-only=<pattern> implies
--verbose-only=<pattern> unless --verbose is also in effect.

Signed-off-by: Thomas Rast <trast@inf.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/README

@@ -126,6 +126,11 @@ appropriately before running "make".
 	the 't/valgrind/' directory and use the commands under
 	't/valgrind/bin/'.
 
+--valgrind-only=<pattern>::
+	Like --valgrind, but the effect is limited to tests with
+	numbers matching <pattern>.  The number matched against is
+	simply the running count of the test within the file.
+
 --tee::
 	In addition to printing the test output to the terminal,
 	write it to files named 't/test-results/$TEST_NAME.out'.

t/test-lib.sh

@@ -201,6 +201,9 @@ do
 	--valgrind=*)
 		valgrind=$(expr "z$1" : 'z[^=]*=\(.*\)')
 		shift ;;
+	--valgrind-only=*)
+		valgrind_only=$(expr "z$1" : 'z[^=]*=\(.*\)')
+		shift ;;
 	--tee)
 		shift ;; # was handled already
 	--root=*)
@@ -211,7 +214,14 @@ do
 	esac
 done
 
-test -n "$valgrind" && verbose=t
+if test -n "$valgrind_only"
+then
+	test -z "$valgrind" && valgrind=memcheck
+	test -z "$verbose" && verbose_only="$valgrind_only"
+elif test -n "$valgrind"
+then
+	verbose=t
+fi
 
 if test -n "$color"
 then
@@ -371,6 +381,25 @@ maybe_setup_verbose () {
 	last_verbose=$verbose
 }
 
+maybe_teardown_valgrind () {
+	test -z "$GIT_VALGRIND" && return
+	GIT_VALGRIND_ENABLED=
+}
+
+maybe_setup_valgrind () {
+	test -z "$GIT_VALGRIND" && return
+	if test -z "$valgrind_only"
+	then
+		GIT_VALGRIND_ENABLED=t
+		return
+	fi
+	GIT_VALGRIND_ENABLED=
+	if match_pattern_list $test_count $valgrind_only
+	then
+		GIT_VALGRIND_ENABLED=t
+	fi
+}
+
 test_eval_ () {
 	# This is a separate function because some tests use
 	# "return" to end a test_expect_success block early.
@@ -401,10 +430,12 @@ test_run_ () {
 test_start_ () {
 	test_count=$(($test_count+1))
 	maybe_setup_verbose
+	maybe_setup_valgrind
 }
 
 test_finish_ () {
 	echo >&3 ""
+	maybe_teardown_valgrind
 	maybe_teardown_verbose
 }
 
@@ -590,6 +621,9 @@ then
 	export GIT_VALGRIND
 	GIT_VALGRIND_MODE="$valgrind"
 	export GIT_VALGRIND_MODE
+	GIT_VALGRIND_ENABLED=t
+	test -n "$valgrind_only" && GIT_VALGRIND_ENABLED=
+	export GIT_VALGRIND_ENABLED
 elif test -n "$GIT_TEST_INSTALLED"
 then
 	GIT_EXEC_PATH=$($GIT_TEST_INSTALLED/git --exec-path)  ||

t/valgrind/valgrind.sh

@@ -4,6 +4,9 @@ base=$(basename "$0")
 
 TOOL_OPTIONS='--leak-check=no'
 
+test -z "$GIT_VALGRIND_ENABLED" &&
+exec "$GIT_VALGRIND"/../../"$base" "$@"
+
 case "$GIT_VALGRIND_MODE" in
 memcheck-fast)
 	;;