fix: Refactored section split logic (#200)

Co-authored-by: Kevin Partington <kevin.partington@kernelpanicstudios.com>

lib/ini.js

@@ -33,7 +33,7 @@ const encode = (obj, opt = {}) => {
   }
 
   for (const k of children) {
-    const nk = dotSplit(k).join('\\.')
+    const nk = splitSections(k, '.').join('\\.')
     const section = (opt.section ? opt.section + '.' : '') + nk
     const child = encode(obj[k], {
       ...opt,
@@ -49,13 +49,31 @@ const encode = (obj, opt = {}) => {
   return out
 }
 
-const dotSplit = str =>
-  str.replace(/\1/g, '\u0002LITERAL\\1LITERAL\u0002')
-    .replace(/\\\./g, '\u0001')
-    .split(/\./)
-    .map(part =>
-      part.replace(/\1/g, '\\.')
-        .replace(/\2LITERAL\\1LITERAL\2/g, '\u0001'))
+function splitSections (str, separator) {
+  var lastMatchIndex = 0
+  var lastSeparatorIndex = 0
+  var nextIndex = 0
+  var sections = []
+
+  do {
+    nextIndex = str.indexOf(separator, lastMatchIndex)
+
+    if (nextIndex !== -1) {
+      lastMatchIndex = nextIndex + separator.length
+
+      if (nextIndex > 0 && str[nextIndex - 1] === '\\') {
+        continue
+      }
+
+      sections.push(str.slice(lastSeparatorIndex, nextIndex))
+      lastSeparatorIndex = nextIndex + separator.length
+    }
+  } while (nextIndex !== -1)
+
+  sections.push(str.slice(lastSeparatorIndex))
+
+  return sections
+}
 
 const decode = str => {
   const out = Object.create(null)
@@ -126,7 +144,7 @@ const decode = str => {
 
     // see if the parent section is also an object.
     // if so, add it to that, and mark this one for deletion
-    const parts = dotSplit(k)
+    const parts = splitSections(k, '.')
     p = out
     const l = parts.pop()
     const nl = l.replace(/\\\./g, '.')