diff --git a/docs/source/usage/shell-prompts.rst b/docs/source/usage/shell-prompts.rst
index 0a5c1f38..1ddb0a14 100644
--- a/docs/source/usage/shell-prompts.rst
+++ b/docs/source/usage/shell-prompts.rst
@@ -111,7 +111,7 @@ following in ``~/.profile``:
 
 .. code-block:: bash
 
-    if test "x$0" != "x${0#dash}" ; then
+    if test "$0" != "${0#dash}" ; then
         export ENV={repository_root}/powerline/bindings/shell/powerline.sh
     fi
 
diff --git a/powerline/bindings/bash/powerline.sh b/powerline/bindings/bash/powerline.sh
index 75f8e08d..377c41a8 100644
--- a/powerline/bindings/bash/powerline.sh
+++ b/powerline/bindings/bash/powerline.sh
@@ -21,7 +21,7 @@ _powerline_tmux_setenv() {
 }
 
 _powerline_tmux_set_pwd() {
-	if test "x$_POWERLINE_SAVED_PWD" != "x$PWD" ; then
+	if test "$_POWERLINE_SAVED_PWD" != "$PWD" ; then
 		_POWERLINE_SAVED_PWD="$PWD"
 		_powerline_tmux_setenv PWD "$PWD"
 	fi
@@ -39,8 +39,8 @@ _powerline_init_tmux_support() {
 		trap '_powerline_tmux_set_columns' WINCH
 		_powerline_tmux_set_columns
 
-		test "x$PROMPT_COMMAND" != "x${PROMPT_COMMAND/_powerline_tmux_set_pwd}" ||
-			PROMPT_COMMAND="${PROMPT_COMMAND}"$'\n_powerline_tmux_set_pwd'
+		test "$PROMPT_COMMAND" != "${PROMPT_COMMAND/_powerline_tmux_set_pwd}" \
+			|| PROMPT_COMMAND="${PROMPT_COMMAND}"$'\n_powerline_tmux_set_pwd'
 	fi
 }
 
@@ -82,8 +82,8 @@ _powerline_setup_prompt() {
 	if test -z "${POWERLINE_COMMAND}" ; then
 		POWERLINE_COMMAND="$("$POWERLINE_CONFIG_COMMAND" shell command)"
 	fi
-	test "x$PROMPT_COMMAND" != "x${PROMPT_COMMAND%_powerline_set_prompt*}" ||
-		PROMPT_COMMAND=$'_powerline_set_prompt\n'"${PROMPT_COMMAND}"
+	test "$PROMPT_COMMAND" != "${PROMPT_COMMAND%_powerline_set_prompt*}" \
+		|| PROMPT_COMMAND=$'_powerline_set_prompt\n'"${PROMPT_COMMAND}"
 	PS2="$(_powerline_local_prompt left -r.bash 0 0 continuation)"
 	PS3="$(_powerline_local_prompt left '' 0 0 select)"
 }
diff --git a/powerline/bindings/fish/powerline-setup.fish b/powerline/bindings/fish/powerline-setup.fish
index 44d03287..3887138f 100644
--- a/powerline/bindings/fish/powerline-setup.fish
+++ b/powerline/bindings/fish/powerline-setup.fish
@@ -34,7 +34,7 @@ function powerline-setup
 			set -g POWERLINE_COMMAND (env $POWERLINE_CONFIG_COMMAND shell command)
 		end
 		function _powerline_set_default_mode --on-variable fish_key_bindings
-			if test x$fish_key_bindings != xfish_vi_key_bindings
+			if test $fish_key_bindings != fish_vi_key_bindings
 				set -g _POWERLINE_DEFAULT_MODE default
 			else
 				set -g -e _POWERLINE_DEFAULT_MODE
diff --git a/powerline/bindings/rc/powerline.rc b/powerline/bindings/rc/powerline.rc
index a6d96eff..b2d6538f 100644
--- a/powerline/bindings/rc/powerline.rc
+++ b/powerline/bindings/rc/powerline.rc
@@ -37,7 +37,7 @@ fn _powerline_common_setup {
 }
 
 fn _powerline_tmux_pane {
-	if (test x$TMUX_PANE '!=' x) {
+	if (test -n $TMUX_PANE) {
 		echo $TMUX_PANE | tr -d ' %'
 	} else {
 		TMUX=$_POWERLINE_TMUX tmux display -p '#D' | tr -d ' %'
@@ -54,9 +54,9 @@ if (test -z $POWERLINE_CONFIG_COMMAND) {
 		echo powerline-config executable not found, unable to proceed >[2=1]
 	}
 }
-if (test x$POWERLINE_CONFIG_COMMAND '!=' x) {
+if (test -n $POWERLINE_CONFIG_COMMAND) {
 	if ($POWERLINE_CONFIG_COMMAND shell --shell rcsh uses prompt) {
-		if (test x$POWERLINE_COMMAND_ARGS '!=' x) {
+		if (test -n $POWERLINE_COMMAND_ARGS) {
 			# Perform splitting
 			POWERLINE_COMMAND_ARGS=( `{echo $POWERLINE_COMMAND_ARGS} )
 		}
@@ -75,11 +75,11 @@ if (test x$POWERLINE_CONFIG_COMMAND '!=' x) {
 		}
 		_powerline_common_setup
 	}
-	if (test x$TMUX '!=' x) {
+	if (test -n $TMUX) {
 		if ($POWERLINE_CONFIG_COMMAND shell --shell rcsh uses tmux) {
 			_POWERLINE_TMUX=$TMUX
 			fn _powerline_tmux_setenv {
-				if (test x$2 '!=' x) {
+				if (test -n $2) {
 					TMUX=$_POWERLINE_TMUX tmux setenv -g TMUX_$1^_`{
 						_powerline_tmux_pane
 					} $2
diff --git a/powerline/bindings/shell/powerline.sh b/powerline/bindings/shell/powerline.sh
index d2339a1b..15e13f26 100644
--- a/powerline/bindings/shell/powerline.sh
+++ b/powerline/bindings/shell/powerline.sh
@@ -115,7 +115,7 @@ _powerline_tmux_setenv() {
 }
 
 _powerline_tmux_set_pwd() {
-	if test "x$_POWERLINE_SAVED_PWD" != "x$PWD" ; then
+	if test "$_POWERLINE_SAVED_PWD" != "$PWD" ; then
 		_POWERLINE_SAVED_PWD="$PWD"
 		_powerline_tmux_setenv PWD "$PWD"
 	fi
diff --git a/tests/shlib/common.sh b/tests/shlib/common.sh
index ea208ff8..a95d8044 100644
--- a/tests/shlib/common.sh
+++ b/tests/shlib/common.sh
@@ -30,14 +30,14 @@ exit_suite() {
 		echo "${FAIL_SUMMARY}"
 	fi
 	export POWERLINE_CURRENT_SUITE="${POWERLINE_CURRENT_SUITE%/*}"
-	if test "x$1" != "x--continue" ; then
+	if test "$1" != "--continue" ; then
 		exit $FAILED
 	fi
 }
 
 fail() {
 	local allow_failure=
-	if test "x$1" = "x--allow-failure" ; then
+	if test "$1" = "--allow-failure" ; then
 		shift
 		allow_failure=A
 	fi
@@ -48,7 +48,7 @@ fail() {
 	FAIL_SUMMARY="${FAIL_SUMMARY}${NL}${full_msg}"
 	echo "Failed: $full_msg"
 	echo "$full_msg" >> "$FAILURES_FILE"
-	if test "x$allow_failure" = "x" ; then
+	if test -z "$allow_failure" ; then
 		FAILED=1
 	fi
 }
diff --git a/tests/test_awesome/test.sh b/tests/test_awesome/test.sh
index eb08f453..93d50303 100755
--- a/tests/test_awesome/test.sh
+++ b/tests/test_awesome/test.sh
@@ -30,7 +30,7 @@ for pexe in powerline powerline.sh powerline.py ; do
 	else
 		continue
 	fi
-	if test "x$pexe" != 'xpowerline.sh' || test -e "$TEST_PATH/socat" ; then
+	if test "$pexe" != 'powerline.sh' || test -e "$TEST_PATH/socat" ; then
 		POWERLINE_COMMAND="$pexe"
 		break
 	fi
@@ -74,7 +74,7 @@ check_log() {
 		return 1
 	fi
 	local expline="powerline_widget:set_markup('<span foreground=\"#303030\"> </span><span foreground=\"#d0d0d0\" background=\"#303030\" font_weight=\"bold\"> default-right </span>')"
-	if test "x$expline" != "x$line" ; then
+	if test "$expline" != "$line" ; then
 		echo "Line:     '$line'"
 		echo "Expected: '$expline'"
 		fail "log:line" F "Unexpected line"
@@ -119,7 +119,7 @@ else
 		sleep 5
 		killscript "$(cat "$TEST_ROOT/$args-pid")"
 		rm "$TEST_ROOT/$args-pid"
-		if test "x$(cat "$DEPRECATED_LOG")" != "x" ; then
+		if test -n "$(cat "$DEPRECATED_LOG")" ; then
 			display_log "$DEPRECATED_LOG"
 			fail "output" E "Nonempty $DEPRECATED_SCRIPT output"
 		fi
@@ -153,7 +153,7 @@ run "$POWERLINE_COMMAND" --socket $ADDRESS wm.awesome > "$TEST_ROOT/output.log.3
 run "$POWERLINE_COMMAND" --socket $ADDRESS wm.awesome > "$TEST_ROOT/output.log.4" 2>&1
 run "$POWERLINE_COMMAND" --socket $ADDRESS wm.awesome > "$TEST_ROOT/output.log.5" 2>&1
 for log_file in "$TEST_ROOT"/output.log.* ; do
-	if test "x$(cat "$log_file")" != "x" ; then
+	if test -n "$(cat "$log_file")" ; then
 		display_log "$log_file"
 		fail "output" E "Nonempty $POWERLINE_COMMAND output at run ${log_file#*.}"
 	fi
@@ -161,13 +161,13 @@ for log_file in "$TEST_ROOT"/output.log.* ; do
 done
 sleep 5
 run python "$POWERLINE_DAEMON" --socket $ADDRESS --quiet --kill > "$TEST_ROOT/kill.log" 2>&1
-if test "x$(cat "$TEST_ROOT/kill.log")" != "x" ; then
+if test -n "$(cat "$TEST_ROOT/kill.log")" ; then
 	display_log "$TEST_ROOT/kill.log"
 	fail "daemonlog" E "Nonempty kill log"
 fi
 rm "$TEST_ROOT/kill.log"
 wait $DPID
-if test "x$(cat "$TEST_ROOT/daemon.log")" != "x" ; then
+if test -n "$(cat "$TEST_ROOT/daemon.log")" ; then
 	display_log "$TEST_ROOT/daemon.log"
 	fail "daemonlog" E "Nonempty daemon log"
 fi
diff --git a/tests/test_bar/test.sh b/tests/test_bar/test.sh
index 88fe57c5..d6522eed 100755
--- a/tests/test_bar/test.sh
+++ b/tests/test_bar/test.sh
@@ -49,7 +49,7 @@ check_log() {
 	if test "$warns" = "warns" ; then
 		local warning="$(head -n1 "$log_file" | sed 's/.*://')"
 		local expwarning="The 'bar' bindings are deprecated, please switch to 'lemonbar'"
-		if test "x$warning" != "x$expwarning" ; then
+		if test "$warning" != "$expwarning" ; then
 			echo "Got: $warning"
 			echo "Exp: $expwarning"
 			fail "warn" F "Expected warning"
@@ -66,7 +66,7 @@ check_log() {
 		return 1
 	fi
 	local expline="%{l}%{F#ffd0d0d0}%{B#ff303030} $text-left %{F-B--u}%{F#ff303030} %{F-B--u}%{r}%{F#ff303030} %{F-B--u}%{F#ffd0d0d0}%{B#ff303030} $text-right %{F-B--u}"
-	if test "x$expline" != "x$line" ; then
+	if test "$expline" != "$line" ; then
 		echo "Line:     '$line'"
 		echo "Expected: '$expline'"
 		fail "log:line" F "Unexpected line"
@@ -149,14 +149,14 @@ else
 		if test "$fnum" -ne 2 ; then
 			fail "fnum" F "Expected two output files"
 		fi
-		if test "x${args#--height}" != "x$args" ; then
+		if test "${args#--height}" != "$args" ; then
 			height="${args#--height}"
 			height="${height# }"
 			height="${height#=}"
 			height="${height%% *}"
 		fi
 		command="lemonbar"
-		if test "x${args#--bar-command}" != "x$args" ; then
+		if test "${args#--bar-command}" != "$args" ; then
 			command="${args#--bar-command}"
 			command="${command# }"
 			command="${command#=}"
@@ -166,11 +166,11 @@ else
 		rm "$TEST_ROOT/args.log"
 		script_args="${args#*-- }"
 		script_args="${script_args# }"
-		if test "x${script_args}" '=' "x$args" ; then
+		if test "${script_args}" = "$args" ; then
 			script_args=
 		fi
 		expected_args="$command -g 1920x$height+0${script_args:+ }$script_args${NL}$command -g 1920x$height+1${script_args:+ }$script_args"
-		if test "x$expected_args" != "x$received_args" ; then
+		if test "$expected_args" != "$received_args" ; then
 			echo "args:${NL}<$received_args>"
 			echo "expected:${NL}<$expected_args>"
 			fail "args" F "Expected different args"
diff --git a/tests/test_shells/test.sh b/tests/test_shells/test.sh
index c267b452..1dce46db 100755
--- a/tests/test_shells/test.sh
+++ b/tests/test_shells/test.sh
@@ -12,7 +12,7 @@ ONLY_TEST_CLIENT="$3"
 
 export PYTHON
 
-if test "x$ONLY_SHELL" = "x--help" ; then
+if test "$ONLY_SHELL" = "--help" ; then
 cat << EOF
 Usage:
 	$0 [[[ONLY_SHELL | ""] (ONLY_TEST_TYPE | "")] (ONLY_TEST_CLIENT | "")]
@@ -53,7 +53,7 @@ print_full_output() {
 	cat "$TEST_ROOT/${SH}.${TEST_TYPE}.${TEST_CLIENT}.full.log"
 	echo
 	echo '____________________________________________________________'
-	if test "x$POWERLINE_TEST_NO_CAT_V" != "x1" ; then
+	if test "$POWERLINE_TEST_NO_CAT_V" != "1" ; then
 		echo "Full output (cat -v):"
 		echo '============================================================'
 		cat -v "$TEST_ROOT/${SH}.${TEST_TYPE}.${TEST_CLIENT}.full.log"
@@ -71,9 +71,9 @@ do_run_test() {
 
 	local wait_for_echo_arg=
 	if ( \
-		test "x${SH}" = "xdash" \
+		test "${SH}" = "dash" \
 		|| ( \
-			test "x${SH}" = "xpdb" \
+			test "${SH}" = "pdb" \
 			&& ( \
 				( \
 					test "$PYTHON_VERSION_MAJOR" -eq 3 \
@@ -84,7 +84,7 @@ do_run_test() {
 			) \
 		) \
 		|| ( \
-			test "x${SH}" = "xipython" \
+			test "${SH}" = "ipython" \
 			&& test "$("${PYTHON}" -mIPython --version | head -n1 | cut -d. -f1)" -ge 5 \
 		) \
 	) ; then
@@ -95,7 +95,7 @@ do_run_test() {
 		"$@"
 	if ! check_screen_log ${TEST_TYPE} ${TEST_CLIENT} ${SH} ; then
 		echo '____________________________________________________________'
-		if test "x$POWERLINE_TEST_NO_CAT_V" != "x1" ; then
+		if test "$POWERLINE_TEST_NO_CAT_V" != "1" ; then
 			# Repeat the diff to make it better viewable in travis output
 			echo "Diff (cat -v):"
 			echo '============================================================'
@@ -388,7 +388,7 @@ if ( \
 					fi
 				fi
 				SH="${TEST_COMMAND%% *}"
-				if test "$ONLY_SHELL" != "" && test "x$ONLY_SHELL" != "x$SH" ; then
+				if test -n "$ONLY_SHELL" && test "$ONLY_SHELL" != "$SH" ; then
 					continue
 				fi
 				if ! test -x "$TEST_ROOT/path/$SH" ; then
@@ -396,13 +396,7 @@ if ( \
 				fi
 				echo ">>> $(readlink "$TEST_ROOT/path/$SH")"
 				if ! run_test $TEST_TYPE $TEST_CLIENT $TEST_COMMAND ; then
-					ALLOW_FAILURE_ARG=
-					# dash tests are not stable, see #931
-					# also do not allow fish tests to spoil the build
-					if test x$FAST$SH = x1dash || test x$FAST$SH = x1fish ; then
-						ALLOW_FAILURE_ARG="--allow-failure"
-					fi
-					fail $ALLOW_FAILURE_ARG "$SH-$TEST_TYPE-$TEST_CLIENT:test" F \
+					fail "$SH-$TEST_TYPE-$TEST_CLIENT:test" F \
 						"Failed checking $TEST_COMMAND"
 				fi
 			done