fix(yaml): make parse_yaml() shellcheck compliant

stream-sprout

@@ -12,18 +12,23 @@ function ctrl_c() {
 
 # https://stackoverflow.com/questions/5014632/how-can-i-parse-a-yaml-file-from-a-linux-shell-script
 function parse_yaml() {
-   local prefix=$2
-   local s='[[:space:]]*' w='[a-zA-Z0-9_]*' fs=$(echo @|tr @ '\034')
-   sed -ne "s|^\($s\):|\1|" \
-        -e "s|^\($s\)\($w\)$s:$s[\"']\(.*\)[\"']$s\$|\1$fs\2$fs\3|p" \
-        -e "s|^\($s\)\($w\)$s:$s\(.*\)$s\$|\1$fs\2$fs\3|p"  $1 |
-   awk -F$fs '{
+   local prefix="${2}"
+   local s=""
+   local w=""
+   local fs=""
+   s='[[:space:]]*'
+   w='[a-zA-Z0-9_]*'
+   fs=$(echo @|tr @ '\034')
+   sed -ne "s|^\(${s}\):|\1|" \
+        -e "s|^\(${s}\)\(${w}\)${s}:${s}[\"']\(.*\)[\"']$s\$|\1${fs}\2${fs}\3|p" \
+        -e "s|^\(${s}\)\(${w}\)${s}:${s}\(.*\)${s}\$|\1${fs}\2${fs}\3|p" "${1}" |
+   awk -F"${fs}" '{
       indent = length($1)/2;
       vname[indent] = $2;
       for (i in vname) {if (i > indent) {delete vname[i]}}
       if (length($3) > 0) {
          vn=""; for (i=0; i<indent; i++) {vn=(vn)(vname[i])("_")}
-         printf("%s%s%s=\"%s\"\n", "'$prefix'",vn, $2, $3);
+         printf("%s%s%s=\"%s\"\n", "'"${prefix}"'",vn, $2, $3);
       }
    }'
 }