fix: preserve single-quoted values on decode/encode round-trip

lib/ini.js

@@ -1,5 +1,31 @@
 const { hasOwnProperty } = Object.prototype
 
+// Remember which keys were written with single quotes so stringify can
+// restore them. Parse still unquotes the JS value (see PR #16).
+const singleQuotedKeys = new WeakMap()
+
+const markSingleQuoted = (obj, key) => {
+  let keys = singleQuotedKeys.get(obj)
+  if (!keys) {
+    keys = new Set()
+    singleQuotedKeys.set(obj, keys)
+  }
+  keys.add(key)
+}
+
+const emitValue = (obj, key, val) => {
+  const keys = singleQuotedKeys.get(obj)
+  if (!keys || !keys.has(key)) {
+    return safe(val)
+  }
+  const inner = typeof val === 'string' ? val : String(val)
+  // A raw `'` inside the value would break single-quote wrapping.
+  if (inner.includes("'")) {
+    return safe(val)
+  }
+  return "'" + inner + "'"
+}
+
 const encode = (obj, opt = {}) => {
   if (typeof opt === 'string') {
     opt = { section: opt }
@@ -52,7 +78,7 @@ const encode = (obj, opt = {}) => {
     } else if (val && typeof val === 'object') {
       children.push(k)
     } else {
-      out += safe(k).padEnd(padToChars, ' ') + separator + safe(val) + eol
+      out += safe(k).padEnd(padToChars, ' ') + separator + emitValue(obj, k, val) + eol
     }
   }
 
@@ -146,6 +172,8 @@ const decode = (str, opt = {}) => {
     if (key === '__proto__') {
       continue
     }
+    const trimmedValue = match[3] ? (match[4] || '').trim() : ''
+    const wasSingleQuoted = isQuoted(trimmedValue) && trimmedValue.startsWith("'")
     const valueRaw = match[3] ? unsafe(match[4]) : true
     const value = valueRaw === 'true' ||
       valueRaw === 'false' ||
@@ -167,6 +195,9 @@ const decode = (str, opt = {}) => {
       p[key].push(value)
     } else {
       p[key] = value
+      if (wasSingleQuoted) {
+        markSingleQuoted(p, key)
+      }
     }
   }
 

tap-snapshots/test/foo.js.test.cjs

@@ -70,13 +70,13 @@ o=p
 a with spaces=b  c
 " xa  n          p "="\\"\\r\\nyoyoyo\\r\\r\\n"
 "[disturbing]"=hey you never know
-s=something
+s='something'
 s1="something'
 s2=something else
 s3=
 s4=
-s5="   "
-s6=" a "
+s5='   '
+s6=' a '
 s7=true
 true=true
 false=false
@@ -116,13 +116,13 @@ o                    = p
 a with spaces        = b  c
 " xa  n          p " = "\\"\\r\\nyoyoyo\\r\\r\\n"
 "[disturbing]"       = hey you never know
-s                    = something
+s                    = 'something'
 s1                   = "something'
 s2                   = something else
 s3                   = 
 s4                   = 
-s5                   = "   "
-s6                   = " a "
+s5                   = '   '
+s6                   = ' a '
 s7                   = true
 true                 = true
 false                = false
@@ -169,13 +169,13 @@ eq                   = "eq=eq"
 false                = false
 null                 = null
 o                    = p
-s                    = something
+s                    = 'something'
 s1                   = "something'
 s2                   = something else
 s3                   = 
 s4                   = 
-s5                   = "   "
-s6                   = " a "
+s5                   = '   '
+s6                   = ' a '
 s7                   = true
 true                 = true
 undefined            = undefined
@@ -249,13 +249,13 @@ eq="eq=eq"
 false=false
 null=null
 o=p
-s=something
+s='something'
 s1="something'
 s2=something else
 s3=
 s4=
-s5="   "
-s6=" a "
+s5='   '
+s6=' a '
 s7=true
 true=true
 undefined=undefined

test/single-quotes.js

@@ -0,0 +1,82 @@
+const ini = require('../')
+const t = require('tap')
+
+const issue242 = `ActiveIndex = '0'
+MaximizedFlag = '1911'
+ProductVersion = '14.0.25793.400'
+Version = '1'
+WindowCount = '1'`
+
+t.test('decode then encode preserves single-quoted values (#242)', t => {
+  const parsed = ini.parse(issue242)
+
+  // Parse still unquotes for JS consumers (PR #16)
+  t.equal(parsed.ActiveIndex, 0)
+  t.equal(parsed.MaximizedFlag, 1911)
+  t.equal(parsed.ProductVersion, '14.0.25793.400')
+  t.equal(parsed.Version, 1)
+  t.equal(parsed.WindowCount, 1)
+
+  const encoded = ini.stringify(parsed)
+  t.equal(encoded, [
+    "ActiveIndex='0'",
+    "MaximizedFlag='1911'",
+    "ProductVersion='14.0.25793.400'",
+    "Version='1'",
+    "WindowCount='1'",
+    '',
+  ].join('\n'))
+  t.end()
+})
+
+t.test('unquoted safe values stay unquoted', t => {
+  t.equal(ini.stringify(ini.parse('ActiveIndex = 0')), 'ActiveIndex=0\n')
+  t.equal(ini.stringify(ini.parse('name = something')), 'name=something\n')
+  t.equal(ini.stringify({ ActiveIndex: 0 }), 'ActiveIndex=0\n')
+  t.equal(ini.stringify({ ActiveIndex: '0' }), 'ActiveIndex=0\n')
+  t.end()
+})
+
+t.test('double-quoted safe values are still unquoted on encode', t => {
+  t.equal(ini.stringify(ini.parse('name = "something"')), 'name=something\n')
+  t.equal(ini.stringify(ini.parse('s2 = "something else"')), 's2=something else\n')
+  t.end()
+})
+
+t.test('double quotes still used for special characters', t => {
+  t.equal(ini.stringify({ eq: 'eq=eq' }), 'eq="eq=eq"\n')
+  t.equal(ini.stringify(ini.parse('eq = "eq=eq"')), 'eq="eq=eq"\n')
+  t.end()
+})
+
+t.test('whitespace option keeps restored single quotes', t => {
+  const encoded = ini.stringify(ini.parse("ActiveIndex = '0'"), { whitespace: true })
+  t.equal(encoded, "ActiveIndex = '0'\n")
+  t.end()
+})
+
+t.test('mixed quoted and unquoted keys in one object', t => {
+  const parsed = ini.parse("quoted = '1'\nplain = 2\n")
+  t.equal(ini.stringify(parsed), "quoted='1'\nplain=2\n")
+  t.end()
+})
+
+t.test('single-quoted value containing a quote falls back to safe()', t => {
+  const parsed = ini.parse("odd = 'a'b'\n")
+  t.equal(parsed.odd, "a'b")
+  t.equal(ini.stringify(parsed), "odd=a'b\n")
+  t.end()
+})
+
+t.test('single quotes are preserved inside sections', t => {
+  const parsed = ini.parse("[window]\nActiveIndex = '0'\nTitle = unquoted\n")
+  t.equal(parsed.window.ActiveIndex, 0)
+  t.equal(parsed.window.Title, 'unquoted')
+  t.equal(ini.stringify(parsed), "[window]\nActiveIndex='0'\nTitle=unquoted\n")
+  t.end()
+})
+
+t.test('empty single-quoted value round-trips', t => {
+  t.equal(ini.stringify(ini.parse("x = ''")), "x=''\n")
+  t.end()
+})