Update dotfile option parsing and complete tests

src/lib/parse-dotfile-options.sh

@@ -1,38 +1,36 @@
+# Parse Dotfile options and set relevant global variables.
 parse-dotfile-options() {
   OPT_ROOT_LINK="$(parse-dotfile-root_link-option)"
   OPT_DEFAULT_ACTION="$(parse-dotfile-default_action-option)"
 }
 
-parse-dotfile-root_link-option() {
-  local dotfile="$DOTFILE"
-  if [ -n "$1" ]; then dotfile="$1"; fi
-
-  # Set default.
-  local root_link=".dotfiles"
+# Extract a specific option from Dotfile.
+#
+# Arguments:
+#   - $1: Name of option to extract.
+#   - $2: (optional) Default value of option if not present in Dotfile.
+#   - $3: (optional) Specific Dotfile to read. Uses $DOTFILE if empty.
+#
+parse-dotfile-option() {
+  local name="$1"
+  local value="$2"
+  local dotfile="$3"
+  if [ -z "$dotfile" ]; then dotfile="$DOTFILE"; fi
 
   while read line; do
-    if [[ "$line" == "root_link "* ]]; then
-      root_link="$(trim "${line/#root_link /}")"
+    if [[ "$line" == "$name "* ]]; then
+      value="$(trim "${line/#$name }")"
       break
     fi
   done < "$dotfile"
 
-  echo "$root_link"
+  echo "$value"
+}
+
+parse-dotfile-root_link-option() {
+  echo "$(parse-dotfile-option "root_link" ".dotfiles" "$1")"
 }
 
 parse-dotfile-default_action-option() {
-  local dotfile="$DOTFILE"
-  if [ -n "$1" ]; then dotfile="$1"; fi
-
-  # Set default value.
-  default_action="link"
-
-  while read line; do
-    if [[ "$line" == "default_action "* ]]; then
-      default_action="$(trim "${line/#default_action /}")"
-      break
-    fi
-  done < "$dotfile"
-
-  echo "$default_action"
+  echo "$(parse-dotfile-option "default_action" "link" "$1")"
 }