ZTS: Clean up properties.shlib a bit

Fixes the last property having an empty value on FreeBSD and makes the
code a bit more readable.

Reviewed-by: Kjeld Schouten <kjeld@schouten-lebbing.nl>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Ryan Moeller <ryan@ixsystems.com>
Closes #9834

tests/zfs-tests/include/properties.shlib

@@ -34,47 +34,54 @@ typeset -a vol_props=('compress' 'checksum' 'copies' 'logbias' 'primarycache'
     'secondarycache' 'redundant_metadata' 'sync')
 
 #
-# Given the property array passed in, return 'num_props' elements to the
-# user, excluding any elements below 'start.' This allows us to exclude
-# 'off' and 'on' which can be either unwanted, or a duplicate of another
-# property respectively.
+# Given the 'prop' passed in, return 'num_vals' elements of the corresponding
+# values array to the user, excluding any elements below 'first.' This allows
+# us to exclude 'off' and 'on' which can be either unwanted, or a duplicate of
+# another property respectively.
 #
-function get_rand_prop
+function get_rand_prop_vals
 {
-	typeset prop_array=($(eval echo \${$1[@]}))
-	typeset -i num_props=$2
-	typeset -i start=$3
+	typeset prop=$1
+	typeset -i num_vals=$2
+	typeset -i first=$3
+
+	[[ -z $prop || -z $num_vals || -z $first ]] && \
+	    log_fail "get_rand_prop_vals: bad arguments"
+
 	typeset retstr=""
 
-	[[ -z $prop_array || -z $num_props || -z $start ]] && \
-	    log_fail "get_rand_prop: bad arguments"
+	typeset prop_vals_var=${prop}_prop_vals
+	typeset -a prop_vals=($(eval echo \${${prop_vals_var}[@]}))
 
-	typeset prop_max=$((${#prop_array[@]} - 1))
+	[[ -z $prop_vals ]] && \
+	    log_fail "get_rand_prop_vals: bad prop $prop"
+
+	typeset -i last=$((${#prop_vals[@]} - 1))
 	typeset -i i
-	for i in $(range_shuffle $start $prop_max | head -n $num_props); do
-		retstr="${prop_array[$i]} $retstr"
+	for i in $(range_shuffle $first $last | head -n $num_vals); do
+		retstr="${prop_vals[$i]} $retstr"
 	done
 	echo $retstr
 }
 
 function get_rand_checksum
 {
-	get_rand_prop checksum_prop_vals $1 2
+	get_rand_prop_vals checksum $1 2
 }
 
 function get_rand_checksum_any
 {
-	get_rand_prop checksum_prop_vals $1 0
+	get_rand_prop_vals checksum $1 0
 }
 
 function get_rand_recsize
 {
-	get_rand_prop recsize_prop_vals $1 0
+	get_rand_prop_vals recsize $1 0
 }
 
 function get_rand_large_recsize
 {
-	get_rand_prop recsize_prop_vals $1 9
+	get_rand_prop_vals recsize $1 9
 }
 
 #
@@ -137,7 +144,7 @@ function randomize_ds_props
 	fi
 
 	for prop in $proplist; do
-		typeset val=$(get_rand_prop "${prop}_prop_vals" 1 0)
+		typeset val=$(get_rand_prop_vals $prop 1 0)
 		log_must zfs set $prop=$val $ds
 	done
 }