diff --git a/docs/shell.md b/docs/shell.md
index 5c18424a..48673d8c 100644
--- a/docs/shell.md
+++ b/docs/shell.md
@@ -197,7 +197,7 @@ B.java
 # 把参数按行输出方便查看 或是 grep
 $ a2l **/*.sh
 lib/console-text-color-themes.sh
-test-cases/parseOpts-test.sh
+test-cases/parseOpts_test.sh
 test-cases/self-installer.sh
 ...
 ```
diff --git a/test-cases/my_unit_test_lib.sh b/test-cases/my_unit_test_lib.sh
new file mode 100644
index 00000000..63f5fb8d
--- /dev/null
+++ b/test-cases/my_unit_test_lib.sh
@@ -0,0 +1,100 @@
+#!/bin/bash
+# unit test lib
+
+#################################################
+# commons functions
+#################################################
+
+# NOTE: $'foo' is the escape sequence syntax of bash
+readonly __ut_ec=$'\033'      # escape char
+readonly __ut_eend=$'\033[0m' # escape end
+
+__ut_colorEcho() {
+    local color=$1
+    shift
+    # if stdout is console, turn on color output.
+    [ -t 1 ] && echo "${__ut_ec}[1;${color}m$*$__ut_eend" || echo "$*"
+}
+
+redEcho() {
+    __ut_colorEcho 31 "$@"
+}
+
+greenEcho() {
+    __ut_colorEcho 32 "$@"
+}
+
+yellowEcho() {
+    __ut_colorEcho 33 "$@"
+}
+
+blueEcho() {
+    __ut_colorEcho 34 "$@"
+}
+
+fail() {
+    redEcho "TEST FAIL: $*"
+    exit 1
+}
+
+die() {
+    redEcho "Error: $*" 1>&2
+    exit 1
+}
+
+#################################################
+# assertion functions
+#################################################
+
+assertArrayEquals() {
+    (($# == 2 || $# == 3)) || die "assertArrayEquals must 2 or 3 arguments!"
+    local failMsg=""
+    (($# == 3)) && {
+        failMsg=$1
+        shift
+    }
+
+    local a1PlaceHolder="$1[@]"
+    local a2PlaceHolder="$2[@]"
+    local a1=("${!a1PlaceHolder}")
+    local a2=("${!a2PlaceHolder}")
+
+    [ ${#a1[@]} -eq ${#a2[@]} ] || fail "assertArrayEquals array length [${#a1[@]}] != [${#a2[@]}]${failMsg:+: $failMsg}"
+
+    local i
+    for ((i = 0; i < ${#a1[@]}; i++)); do
+        [ "${a1[$i]}" = "${a2[$i]}" ] || fail "assertArrayEquals fail element $i: [${a1[$i]}] != [${a2[$i]}]${failMsg:+: $failMsg}"
+    done
+}
+
+assertEquals() {
+    (($# == 2 || $# == 3)) || die "assertEqual must 2 or 3 arguments!"
+    local failMsg=""
+    (($# == 3)) && {
+        failMsg=$1
+        shift
+    }
+    [ "$1" = "$2" ] || fail "assertEqual fail [$1] != [$2]${failMsg:+: $failMsg}"
+}
+
+assertAllVarsSame() {
+    local test_afterVars
+    test_afterVars=$(declare)
+
+    diff \
+        <(echo "$test_beforeVars" | grep -v '^BASH_\|^_=') \
+        <(echo "$test_afterVars" | grep -v '^BASH_\|^_=\|^FUNCNAME=\|^test_') ||
+        fail "assertAllVarsSame: Unexpected extra global vars!"
+}
+
+assertAllVarsExcludeOptVarsSame() {
+    local test_afterVars
+    test_afterVars=$(declare)
+
+    diff \
+        <(echo "$test_beforeVars" | grep -v '^BASH_\|^_=') \
+        <(echo "$test_afterVars" | grep -v '^BASH_\|^_=\|^FUNCNAME=\|^test_\|^_OPT_\|^_opts_index_name_') ||
+        fail "assertAllVarsExcludeOptVarsSame: Unexpected extra global vars!"
+}
+
+test_beforeVars=$(declare)
diff --git a/test-cases/parseOpts-test.sh b/test-cases/parseOpts_test.sh
similarity index 62%
rename from test-cases/parseOpts-test.sh
rename to test-cases/parseOpts_test.sh
index aca6bdfb..d3aff579 100755
--- a/test-cases/parseOpts-test.sh
+++ b/test-cases/parseOpts_test.sh
@@ -1,76 +1,15 @@
 #!/bin/bash
 
-BASE=`dirname $0`
+BASE="$(dirname "${BASH_SOURCE[0]}")"
 
-. $BASE/../lib/parseOpts.sh
+source "$BASE/../lib/parseOpts.sh"
 
-
-#################################################
-# Util Functions
-#################################################
-
-# NOTE: $'foo' is the escape sequence syntax of bash
-readonly ec=$'\033' # escape char
-readonly eend=$'\033[0m' # escape end
-
-colorEcho() {
-    local color=$1
-    shift
-    # if stdout is console, turn on color output.
-    [ -t 1 ] && echo "${ec}[1;${color}m$*$eend" || echo "$*"
-}
-
-redEcho() {
-    colorEcho 31 "$@"
-}
-
-greenEcho() {
-    colorEcho 32 "$@"
-}
-
-yellowEcho() {
-    colorEcho 33 "$@"
-}
-
-blueEcho() {
-    colorEcho 34 "$@"
-}
-
-arrayEquals() {
-    local a1PlaceHolder="$1[@]"
-    local a2PlaceHolder="$2[@]"
-    local a1=("${!a1PlaceHolder}")
-    local a2=("${!a2PlaceHolder}")
-
-    [ ${#a1[@]} -eq ${#a2[@]} ] || return 1
-
-    local i
-    for((i=0; i<${#a1[@]}; i++)); do
-        [ "${a1[$i]}" = "${a2[$i]}" ] || return 1
-    done
-}
-
-compareAllVars() {
-    local test_afterVars=`declare`
-    diff <(echo "$test_beforeVars" | grep -v '^BASH_\|^_=') <(echo "$test_afterVars" | grep -v '^BASH_\|^_=\|^FUNCNAME=\|^test_')
-}
-
-compareAllVarsExcludeOptVars() {
-    local test_afterVars=`declare`
-    diff <(echo "$test_beforeVars" | grep -v '^BASH_\|^_=') <(echo "$test_afterVars" | grep -v '^BASH_\|^_=\|^FUNCNAME=\|^test_\|^_OPT_\|^_opts_index_name_')
-}
-
-fail() {
-    redEcho "TEST FAIL: $*"
-    exit 1
-}
+source "$BASE/my_unit_test_lib.sh"
 
 #################################################
 # Test
 #################################################
 
-test_beforeVars=`declare`
-
 # ========================================
 blueEcho "Test case: success parse"
 # ========================================
@@ -82,18 +21,25 @@ _opts_showOptValueInfoList
 
 [ $test_exitCode -eq 0 ] || fail "Wrong exit code!"
 [ ${#_OPT_INFO_LIST_INDEX[@]} -eq 4 ] || fail "Wrong _OPT_INFO_LIST_INDEX!"
-[ $_OPT_VALUE_a = "true" ] && [ $_OPT_VALUE_a_long  = "true" ] || fail "Wrong option value of a!"
+
+[ $_OPT_VALUE_a = "true" ] && [ $_OPT_VALUE_a_long = "true" ] || fail "Wrong option value of a!"
 [ $_OPT_VALUE_b = "bb" ] && [ $_OPT_VALUE_b_long = "bb" ] || fail "Wrong option value of b!"
+
 test_cArray=(c.sh -p pv -q qv cc)
-arrayEquals test_cArray _OPT_VALUE_c && arrayEquals test_cArray _OPT_VALUE_c_long || fail "Wrong option value of c!"
-test_dArray=(d.sh -x xv d1 d2 d3 ) 
-arrayEquals test_dArray _OPT_VALUE_d && arrayEquals test_dArray _OPT_VALUE_d_long || fail "Wrong option value of d!"
+assertArrayEquals "Wrong option value of c!" test_cArray _OPT_VALUE_c
+assertArrayEquals "Wrong option value of c!" test_cArray _OPT_VALUE_c_long
+
+test_dArray=(d.sh -x xv d1 d2 d3)
+assertArrayEquals "Wrong option value of d!" test_dArray _OPT_VALUE_d
+assertArrayEquals "Wrong option value of d!" test_dArray _OPT_VALUE_d_long
+
 test_argArray=(aa bb cc dd ee)
-arrayEquals test_argArray _OPT_ARGS || fail "Wrong args!"
+assertArrayEquals "Wrong args!" test_argArray _OPT_ARGS
+
+assertAllVarsExcludeOptVarsSame
 
-compareAllVarsExcludeOptVars || fail "Unpected extra glable vars!"
 _opts_cleanOptValueInfoList
-compareAllVars || fail "Unpected extra glable vars!"
+assertAllVarsSame
 
 # ========================================
 blueEcho "Test case: success parse with -- "
@@ -106,18 +52,23 @@ _opts_showOptValueInfoList
 
 [ $test_exitCode -eq 0 ] || fail "Wrong exit code!"
 [ ${#_OPT_INFO_LIST_INDEX[@]} -eq 4 ] || fail "Wrong _OPT_INFO_LIST_INDEX!"
-[ $_OPT_VALUE_a = "true" ] && [ $_OPT_VALUE_a_long  = "true" ] || fail "Wrong option value of a!"
+
+[ $_OPT_VALUE_a = "true" ] && [ $_OPT_VALUE_a_long = "true" ] || fail "Wrong option value of a!"
 [ $_OPT_VALUE_b = "bb" ] && [ $_OPT_VALUE_b_long = "bb" ] || fail "Wrong option value of b!"
+
 test_cArray=(c.sh -p pv -q qv cc)
-arrayEquals test_cArray _OPT_VALUE_c && arrayEquals test_cArray _OPT_VALUE_c_long || fail "Wrong option value of c!"
+assertArrayEquals "Wrong option value of c!" test_cArray _OPT_VALUE_c
+assertArrayEquals "Wrong option value of c!" test_cArray _OPT_VALUE_c_long
+
 [ "$_OPT_VALUE_d" = "" ] && [ "$_OPT_VALUE_d_long" = "" ] || fail "Wrong option value of d!"
+
 test_argArray=(aa bb --d-long d.sh -x xv d1 d2 d3 \; cc dd ee)
-arrayEquals test_argArray _OPT_ARGS || fail "Wrong args!"
+assertArrayEquals "Wrong args!" test_argArray _OPT_ARGS
 
-compareAllVarsExcludeOptVars || fail "Unpected extra glable vars!"
-_opts_cleanOptValueInfoList
-compareAllVars || fail "Unpected extra glable vars!"
+assertAllVarsExcludeOptVarsSame
 
+_opts_cleanOptValueInfoList
+assertAllVarsSame
 
 # ========================================
 blueEcho "Test case: illegal option x"
@@ -130,14 +81,12 @@ _opts_showOptValueInfoList
 
 [ $test_exitCode -eq 232 ] || fail "Wrong exit code!"
 [ ${#_OPT_INFO_LIST_INDEX[@]} -eq 0 ] || fail "Wrong _OPT_INFO_LIST_INDEX!"
-[ "$_OPT_VALUE_a" = "" ] && [ "$_OPT_VALUE_a_long"  = "" ] || fail "Wrong option value of a!"
+[ "$_OPT_VALUE_a" = "" ] && [ "$_OPT_VALUE_a_long" = "" ] || fail "Wrong option value of a!"
 [ "$_OPT_VALUE_b" = "" ] && [ "$_OPT_VALUE_b_long" = "" ] || fail "Wrong option value of b!"
 [ "$_OPT_VALUE_c" = "" ] && [ "$_OPT_VALUE_c_long" = "" ] || fail "Wrong option value of c!"
 [ "$_OPT_VALUE_d" = "" ] && [ "$_OPT_VALUE_d_long" = "" ] || fail "Wrong option value of d!"
 [ "$_OPT_ARGS" = "" ] || fail "Wrong args!"
 
-
-
 # ========================================
 blueEcho "Test case: empty options"
 # ========================================
@@ -149,14 +98,12 @@ _opts_showOptValueInfoList
 
 [ $test_exitCode -eq 0 ] || fail "Wrong exit code!"
 [ ${#_OPT_INFO_LIST_INDEX[@]} -eq 4 ] || fail "Wrong _OPT_INFO_LIST_INDEX!"
-[ "$_OPT_VALUE_a" = "" ] && [ "$_OPT_VALUE_a_long"  = "" ] || fail "Wrong option value of a!"
+[ "$_OPT_VALUE_a" = "" ] && [ "$_OPT_VALUE_a_long" = "" ] || fail "Wrong option value of a!"
 [ "$_OPT_VALUE_b" = "" ] && [ "$_OPT_VALUE_b_long" = "" ] || fail "Wrong option value of b!"
 [ "$_OPT_VALUE_c" = "" ] && [ "$_OPT_VALUE_c_long" = "" ] || fail "Wrong option value of c!"
 [ "$_OPT_VALUE_d" = "" ] && [ "$_OPT_VALUE_d_long" = "" ] || fail "Wrong option value of d!"
 [ "$_OPT_ARGS" = "" ] || fail "Wrong args!"
 
-
-
 # ========================================
 blueEcho "Test case: illegal option name"
 # ========================================
@@ -168,13 +115,12 @@ _opts_showOptValueInfoList
 
 [ $test_exitCode -eq 221 ] || fail "Wrong exit code!"
 [ ${#_OPT_INFO_LIST_INDEX[@]} -eq 0 ] || fail "Wrong _OPT_INFO_LIST_INDEX!"
-[ "$_OPT_VALUE_a" = "" ] && [ "$_OPT_VALUE_a_long"  = "" ] || fail "Wrong option value of a!"
+[ "$_OPT_VALUE_a" = "" ] && [ "$_OPT_VALUE_a_long" = "" ] || fail "Wrong option value of a!"
 [ "$_OPT_VALUE_b" = "" ] && [ "$_OPT_VALUE_b_long" = "" ] || fail "Wrong option value of b!"
 [ "$_OPT_VALUE_c" = "" ] && [ "$_OPT_VALUE_c_long" = "" ] || fail "Wrong option value of c!"
 [ "$_OPT_VALUE_d" = "" ] && [ "$_OPT_VALUE_d_long" = "" ] || fail "Wrong option value of d!"
 [ "$_OPT_ARGS" = "" ] || fail "Wrong args!"
 
-
 parseOpts "a,a-long|b,b-long:|c,c-long+|d,d-long+|z,z-#long" aa -a -b bb -x -c c.sh -p pv -q qv cc \; bb -d d.sh -x xv d1 d2 d3 \; cc -- dd ee
 test_exitCode=$?
 _opts_showOptDescInfoList
@@ -182,12 +128,12 @@ _opts_showOptValueInfoList
 
 [ $test_exitCode -eq 222 ] || fail "Wrong exit code!"
 [ ${#_OPT_INFO_LIST_INDEX[@]} -eq 0 ] || fail "Wrong _OPT_INFO_LIST_INDEX!"
-[ "$_OPT_VALUE_a" = "" ] && [ "$_OPT_VALUE_a_long"  = "" ] || fail "Wrong option value of a!"
+[ "$_OPT_VALUE_a" = "" ] && [ "$_OPT_VALUE_a_long" = "" ] || fail "Wrong option value of a!"
 [ "$_OPT_VALUE_b" = "" ] && [ "$_OPT_VALUE_b_long" = "" ] || fail "Wrong option value of b!"
 [ "$_OPT_VALUE_c" = "" ] && [ "$_OPT_VALUE_c_long" = "" ] || fail "Wrong option value of c!"
 [ "$_OPT_VALUE_d" = "" ] && [ "$_OPT_VALUE_d_long" = "" ] || fail "Wrong option value of d!"
 [ "$_OPT_ARGS" = "" ] || fail "Wrong args!"
 
-compareAllVars || fail "Unpected extra glable vars!"
+assertAllVarsSame
 
 greenEcho "TEST SUCCESS!!!"