refactor: remove quote for simple assignment, simplify code and impro…

…ve readability 🛠️

more info about assignment see
https://www.gnu.org/software/bash/manual/html_node/Shell-Parameters.html

If value is not given, the variable is assigned the null string. All values undergo...

bin/a2l

@@ -11,7 +11,7 @@
 set -eEuo pipefail
 
 # NOTE: DO NOT declare var PROG as readonly in ONE line!
-PROG="$(basename -- "$0")"
+PROG=$(basename -- "$0")
 readonly PROG
 readonly PROG_VERSION='2.6.0-dev'
 
@@ -20,7 +20,7 @@ readonly PROG_VERSION='2.6.0-dev'
 ################################################################################
 
 colorPrint() {
-  local color="$1"
+  local color=$1
   shift
   # if stdout is a terminal, turn on color output.
   #   '-t' check: is a terminal?
@@ -94,13 +94,13 @@ readonly args
 readonly -a ROTATE_COLORS=(33 35 36 31 32 37 34)
 COUNT=0
 rotateColorPrint() {
-  local content="$*"
+  local content=$*
 
   # skip color for white space
   if [[ "$content" =~ ^[[:space:]]*$ ]]; then
     printf '%s\n' "$content"
   else
-    local color="${ROTATE_COLORS[COUNT++ % ${#ROTATE_COLORS[@]}]}"
+    local color=${ROTATE_COLORS[COUNT++ % ${#ROTATE_COLORS[@]}]}
     colorPrint "$color" "$content"
   fi
 }

bin/ap

@@ -13,7 +13,7 @@
 set -eEuo pipefail
 
 # NOTE: DO NOT declare var PROG as readonly in ONE line!
-PROG="$(basename -- "$0")"
+PROG=$(basename -- "$0")
 readonly PROG
 readonly PROG_VERSION='2.6.0-dev'
 
@@ -22,7 +22,7 @@ readonly PROG_VERSION='2.6.0-dev'
 ################################################################################
 
 colorPrint() {
-  local color="$1"
+  local color=$1
   shift
   # if stdout is a terminal, turn on color output.
   #   '-t' check: is a terminal?
@@ -46,9 +46,9 @@ die() {
 # How can I get the behavior of GNU's readlink -f on a Mac?
 # https://stackoverflow.com/questions/1055671
 portableReadLink() {
-  local file="$1" uname
+  local file=$1 uname
 
-  uname="$(uname)"
+  uname=$(uname)
   case "$uname" in
   Linux* | CYGWIN* | MINGW*)
     readlink -f -- "$file"
@@ -72,7 +72,7 @@ portableReadLink() {
 }
 
 usage() {
-  local -r exit_code="${1:-0}"
+  local -r exit_code=${1:-0}
   (($# > 0)) && shift
   local -r out=$(((exit_code != 0) + 1))
 

bin/c

@@ -27,7 +27,7 @@
 set -eEuo pipefail
 
 # NOTE: DO NOT declare var PROG as readonly in ONE line!
-PROG="$(basename -- "$0")"
+PROG=$(basename -- "$0")
 readonly PROG
 readonly PROG_VERSION='2.6.0-dev'
 
@@ -47,7 +47,7 @@ printErrorMsg() {
 }
 
 usage() {
-  local -r exit_code="${1:-0}"
+  local -r exit_code=${1:-0}
   (($# > 0)) && shift
   local -r out=$(((exit_code != 0) + 1))
 
@@ -140,7 +140,7 @@ copy() {
 
 catThenCopy() {
   local content
-  content="$(cat)"
+  content=$(cat)
   if $keep_eol; then
     printf '%s\n' "$content"
   else

bin/coat

@@ -19,13 +19,13 @@ set -eEuo pipefail
 readonly -a ROTATE_COLORS=(33 35 36 31 32 37 34)
 COUNT=0
 rotateColorPrint() {
-  local content="$*"
+  local content=$*
 
   # skip color for white space
   if [[ "$content" =~ ^[[:space:]]*$ ]]; then
     printf '%s\n' "$content"
   else
-    local color="${ROTATE_COLORS[COUNT++ % ${#ROTATE_COLORS[@]}]}"
+    local color=${ROTATE_COLORS[COUNT++ % ${#ROTATE_COLORS[@]}]}
     printf '\e[1;%sm%s\e[0m\n' "$color" "$content"
   fi
 }

bin/cp-into-docker-run

@@ -9,7 +9,7 @@
 # @author Jerry Lee (oldratlee at gmail dot com)
 set -eEuo pipefail
 
-PROG="$(basename -- "$0")"
+PROG=$(basename -- "$0")
 readonly PROG
 readonly PROG_VERSION='2.6.0-dev'
 
@@ -40,9 +40,9 @@ isAbsolutePath() {
 # How can I get the behavior of GNU's readlink -f on a Mac?
 # https://stackoverflow.com/questions/1055671
 portableReadLink() {
-  local file="$1" uname
+  local file=$1 uname
 
-  uname="$(uname)"
+  uname=$(uname)
   case "$uname" in
   Linux* | CYGWIN* | MINGW*)
     readlink -f -- "$file"
@@ -66,7 +66,7 @@ portableReadLink() {
 }
 
 usage() {
-  local -r exit_code="${1:-0}"
+  local -r exit_code=${1:-0}
   (($# > 0)) && shift
   local -r out=$(((exit_code != 0) + 1))
 
@@ -126,23 +126,23 @@ declare -a args=()
 while (($# > 0)); do
   case "$1" in
   -c | --container)
-    container_name="$2"
+    container_name=$2
     shift 2
     ;;
   -u | --docker-user)
-    docker_user="$2"
+    docker_user=$2
     shift 2
     ;;
   -w | --workdir)
-    docker_workdir="$2"
+    docker_workdir=$2
     shift 2
     ;;
   -t | --tmpdir)
-    docker_tmpdir="$2"
+    docker_tmpdir=$2
     shift 2
     ;;
   -p | --cp-path)
-    docker_command_cp_path="$2"
+    docker_command_cp_path=$2
     shift 2
     ;;
   -v | --verbose)
@@ -198,35 +198,35 @@ command -v docker &>/dev/null || die 'docker command not found!'
 # prepare vars for docker operation
 ########################################
 
-readonly specified_run_command="${args[0]}"
-run_command="$specified_run_command"
+readonly specified_run_command=${args[0]}
+run_command=$specified_run_command
 if [ ! -f "$specified_run_command" ]; then
   which "$specified_run_command" &>/dev/null ||
     die "specified command not exists and not found in PATH: $specified_run_command"
 
-  run_command="$(which "$specified_run_command")"
+  run_command=$(which "$specified_run_command")
 fi
-run_command="$(portableReadLink "$run_command")"
-run_command_base_name="$(basename -- "$run_command")"
+run_command=$(portableReadLink "$run_command")
+run_command_base_name=$(basename -- "$run_command")
 readonly run_command run_command_base_name
 
-run_timestamp="$(date "+%Y%m%d_%H%M%S")"
+run_timestamp=$(date "+%Y%m%d_%H%M%S")
 readonly run_timestamp
 readonly uuid="${PROG}_${run_timestamp}_${$}_${RANDOM}"
 
 if [ -n "${docker_command_cp_path}" ]; then
   if isAbsolutePath "$docker_command_cp_path"; then
-    readonly run_command_in_docker="$docker_command_cp_path"
+    readonly run_command_in_docker=$docker_command_cp_path
   else
     readonly run_command_in_docker="${docker_workdir:+"$docker_workdir/"}$docker_command_cp_path"
   fi
-  run_command_dir_in_docker="$(dirname -- "$run_command_in_docker")"
+  run_command_dir_in_docker=$(dirname -- "$run_command_in_docker")
   readonly run_command_dir_in_docker
 else
-  readonly work_tmp_dir_in_docker="$docker_tmpdir/$uuid"
+  readonly work_tmp_dir_in_docker=$docker_tmpdir/$uuid
 
   readonly run_command_in_docker="$work_tmp_dir_in_docker/$run_command_base_name"
-  readonly run_command_dir_in_docker="$work_tmp_dir_in_docker"
+  readonly run_command_dir_in_docker=$work_tmp_dir_in_docker
 fi
 
 cleanupWhenExit() {

bin/echo-args

@@ -9,7 +9,7 @@ set -eEuo pipefail
 digitCount() {
   # argument 1(num) is always a non-negative integer in this script usage,
   # so NO argument validation logic.
-  local num="$1" count=0
+  local num=$1 count=0
   while ((num != 0)); do
     ((++count))
     ((num = num / 10))
@@ -23,7 +23,7 @@ readonly arg_count=$# digit_count
 readonly red='\e[1;31m' blue='\e[1;36m' color_reset='\e[0m'
 
 printArg() {
-  local idx="$1" value="$2"
+  local idx=$1 value=$2
 
   # if stdout is a terminal, turn on color output.
   #   '-t' check: is a terminal?

bin/find-in-jars

@@ -32,7 +32,7 @@
 set -eEuo pipefail
 
 # NOTE: DO NOT declare var PROG as readonly in ONE line!
-PROG="$(basename -- "$0")"
+PROG=$(basename -- "$0")
 readonly PROG
 readonly PROG_VERSION='2.6.0-dev'
 
@@ -74,7 +74,7 @@ printResponsiveMessage() {
     return
   fi
 
-  local content="$*"
+  local content=$*
   # http://www.linuxforums.org/forum/red-hat-fedora-linux/142825-how-truncate-string-bash-script.html
   printf %b%s "${clear_line}" "${content:0:columns}" >&2
 }
@@ -94,7 +94,7 @@ die() {
 }
 
 usage() {
-  local -r exit_code="${1:-0}"
+  local -r exit_code=${1:-0}
   (($# > 0)) && shift
   local -r out=$(((exit_code != 0) + 1))
 
@@ -203,7 +203,7 @@ while (($# > 0)); do
     ;;
   # support the legacy typo option name --seperator for compatibility
   -s | --separator | --seperator)
-    separator="$2"
+    separator=$2
     shift 2
     ;;
   -L | --files-not-contained-found)
@@ -250,7 +250,7 @@ readonly extensions=${extensions:-jar}
 
 (("${#args[@]}" == 0)) && usage 1 "Missing file pattern!"
 (("${#args[@]}" > 1)) && usage 1 "More than 1 file pattern: ${args[*]}"
-readonly pattern="${args[0]}"
+readonly pattern=${args[0]}
 
 declare -a tmp_dirs=()
 for d in "${dirs[@]}"; do
@@ -311,12 +311,12 @@ __prepareCommandToListZipEntries() {
 __prepareCommandToListZipEntries
 
 listZipEntries() {
-  local zip_file="$1" msg
+  local zip_file=$1 msg
 
   if $is_use_zip_cmd_to_list_zip_entries; then
     # How to check if zip file is empty in bash
     # https://superuser.com/questions/438878
-    msg="$("${command_to_list_zip_entries[@]}" -t "$zip_file" 2>&1)" || {
+    msg=$("${command_to_list_zip_entries[@]}" -t "$zip_file" 2>&1) || {
       # NOTE:
       # if list emtpy zip file by zipinfo/unzip command,
       # exit code is 1, and print 'Empty zipfile.'
@@ -344,10 +344,10 @@ searchJarFiles() {
 
   local jar_files total_jar_count
 
-  jar_files="$(find "${dirs[@]}" "${find_iname_options[@]}" -type f)"
+  jar_files=$(find "${dirs[@]}" "${find_iname_options[@]}" -type f)
   [ -n "$jar_files" ] || die "No ${extensions[*]} file found!"
 
-  total_jar_count="$(printf '%s\n' "$jar_files" | wc -l)"
+  total_jar_count=$(printf '%s\n' "$jar_files" | wc -l)
   # remove white space, because the `wc -l` output on mac contains white space!
   total_jar_count=${total_jar_count//[[:space:]]}
 
@@ -356,7 +356,7 @@ searchJarFiles() {
 }
 
 __outputResultOfJarFile() {
-  local jar_file="$1" file jar_color='\e[1;35m' sep_color='\e[1;32m'
+  local jar_file=$1 file jar_color='\e[1;35m' sep_color='\e[1;32m'
   # shellcheck disable=SC2206
   local grep_opt_args=("$regex_mode" ${ignore_case_option:-} ${grep_color_option:-} -- "$pattern")
 

bin/rp

@@ -13,7 +13,7 @@
 set -eEuo pipefail
 
 # NOTE: DO NOT declare var PROG as readonly in ONE line!
-PROG="$(basename -- "$0")"
+PROG=$(basename -- "$0")
 readonly PROG
 readonly PROG_VERSION='2.6.0-dev'
 
@@ -22,7 +22,7 @@ readonly PROG_VERSION='2.6.0-dev'
 ################################################################################
 
 colorPrint() {
-  local color="$1"
+  local color=$1
   shift
   # if stdout is a terminal, turn on color output.
   #   '-t' check: is a terminal?
@@ -44,9 +44,9 @@ die() {
 }
 
 portableRelPath() {
-  local file="$1" relTo="$2" uname
+  local file=$1 relTo=$2 uname
 
-  uname="$(uname)"
+  uname=$(uname)
   case "$uname" in
   Linux* | CYGWIN* | MINGW*)
     realpath "$f" --relative-to="$relTo"
@@ -70,7 +70,7 @@ portableRelPath() {
 }
 
 usage() {
-  local -r exit_code="${1:-0}"
+  local -r exit_code=${1:-0}
   (($# > 0)) && shift
   local -r out=$(((exit_code != 0) + 1))
 
@@ -134,14 +134,14 @@ done
 if [ "${#files[@]}" -eq 1 ]; then
   relativeTo=.
 else
-  argc="${#files[@]}"
+  argc=${#files[@]}
 
   # Get last argument
-  relativeTo="${files[argc - 1]}"
+  relativeTo=${files[argc - 1]}
   files=("${files[@]:0:argc-1}")
 fi
 
-[ -f "$relativeTo" ] && relativeTo="$(dirname -- "$relativeTo")"
+[ -f "$relativeTo" ] && relativeTo=$(dirname -- "$relativeTo")
 [ -e "$relativeTo" ] || die "relativeTo dir($relativeTo) does NOT exists!"
 
 readonly files relativeTo