diff --git a/GIT-VERSION-GEN b/GIT-VERSION-GEN
index e54492f827..7246ab7c78 100755
--- a/GIT-VERSION-GEN
+++ b/GIT-VERSION-GEN
@@ -11,7 +11,7 @@ LF='
 if test -f version
 then
 	VN=$(cat version) || VN="$DEF_VER"
-elif test -d ${GIT_DIR:-.git} -o -f .git &&
+elif { test -d "${GIT_DIR:-.git}" || test -f .git; } &&
 	VN=$(git describe --match "v[0-9]*" HEAD 2>/dev/null) &&
 	case "$VN" in
 	*$LF*) (exit 1) ;;
diff --git a/configure.ac b/configure.ac
index 276593cd9d..d1a96da14e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -94,7 +94,7 @@ AC_DEFUN([GIT_PARSE_WITH_SET_MAKE_VAR],
 [AC_ARG_WITH([$1],
  [AS_HELP_STRING([--with-$1=VALUE], $3)],
  if test -n "$withval"; then
-  if test "$withval" = "yes" -o "$withval" = "no"; then
+  if test "$withval" = "yes" || test "$withval" = "no"; then
     AC_MSG_WARN([You likely do not want either 'yes' or 'no' as]
 		     [a value for $1 ($2).  Maybe you do...?])
   fi
diff --git a/contrib/subtree/git-subtree.sh b/contrib/subtree/git-subtree.sh
index e0c5d3b0de..43b5fec732 100755
--- a/contrib/subtree/git-subtree.sh
+++ b/contrib/subtree/git-subtree.sh
@@ -489,13 +489,13 @@ find_existing_splits () {
 			;;
 		END)
 			debug "Main is: '$main'"
-			if test -z "$main" -a -n "$sub"
+			if test -z "$main" && test -n "$sub"
 			then
 				# squash commits refer to a subtree
 				debug "  Squash: $sq from $sub"
 				cache_set "$sq" "$sub"
 			fi
-			if test -n "$main" -a -n "$sub"
+			if test -n "$main" && test -n "$sub"
 			then
 				debug "  Prior: $main -> $sub"
 				cache_set $main $sub
diff --git a/t/perf/perf-lib.sh b/t/perf/perf-lib.sh
index e7786775a9..b952e5024b 100644
--- a/t/perf/perf-lib.sh
+++ b/t/perf/perf-lib.sh
@@ -31,7 +31,7 @@ unset GIT_CONFIG_NOSYSTEM
 GIT_CONFIG_SYSTEM="$TEST_DIRECTORY/perf/config"
 export GIT_CONFIG_SYSTEM
 
-if test -n "$GIT_TEST_INSTALLED" -a -z "$PERF_SET_GIT_TEST_INSTALLED"
+if test -n "$GIT_TEST_INSTALLED" && test -z "$PERF_SET_GIT_TEST_INSTALLED"
 then
 	error "Do not use GIT_TEST_INSTALLED with the perf tests.
 
diff --git a/t/perf/run b/t/perf/run
index 34115edec3..486ead2198 100755
--- a/t/perf/run
+++ b/t/perf/run
@@ -91,10 +91,10 @@ set_git_test_installed () {
 run_dirs_helper () {
 	mydir=${1%/}
 	shift
-	while test $# -gt 0 -a "$1" != -- -a ! -f "$1"; do
+	while test $# -gt 0 && test "$1" != -- && test ! -f "$1"; do
 		shift
 	done
-	if test $# -gt 0 -a "$1" = --; then
+	if test $# -gt 0 && test "$1" = --; then
 		shift
 	fi
 
@@ -124,7 +124,7 @@ run_dirs_helper () {
 }
 
 run_dirs () {
-	while test $# -gt 0 -a "$1" != -- -a ! -f "$1"; do
+	while test $# -gt 0 && test "$1" != -- && test ! -f "$1"; do
 		run_dirs_helper "$@"
 		shift
 	done
@@ -180,7 +180,8 @@ run_subsection () {
 	GIT_PERF_AGGREGATING_LATER=t
 	export GIT_PERF_AGGREGATING_LATER
 
-	if test $# = 0 -o "$1" = -- -o -f "$1"; then
+	if test $# = 0 || test "$1" = -- || test -f "$1"
+	then
 		set -- . "$@"
 	fi
 
diff --git a/t/valgrind/valgrind.sh b/t/valgrind/valgrind.sh
index 669ebaf68b..3c8ee19975 100755
--- a/t/valgrind/valgrind.sh
+++ b/t/valgrind/valgrind.sh
@@ -23,7 +23,7 @@ memcheck)
 	VALGRIND_MAJOR=$(expr "$VALGRIND_VERSION" : '[^0-9]*\([0-9]*\)')
 	VALGRIND_MINOR=$(expr "$VALGRIND_VERSION" : '[^0-9]*[0-9]*\.\([0-9]*\)')
 	test 3 -gt "$VALGRIND_MAJOR" ||
-	test 3 -eq "$VALGRIND_MAJOR" -a 4 -gt "$VALGRIND_MINOR" ||
+	{ test 3 -eq "$VALGRIND_MAJOR" && test 4 -gt "$VALGRIND_MINOR"; } ||
 	TOOL_OPTIONS="$TOOL_OPTIONS --track-origins=yes"
 	;;
 *)