feat: add platform option to force line endings

This is useful when  generating a file which is not  intended to be used
on the same platform as the current one.  Most embedded system today use
the DOS/Windows format only.

Author: Francois-Xavier Kowalski

README.md

@@ -86,6 +86,10 @@ The `options` object may contain the following:
   after a section header. Some INI file parsers (for example the TOSHIBA
   FlashAir one) need this to parse the file successfully.  By default,
   the additional newline is omitted.
+* `platform` String to define which platform this INI file is expected
+  to be used with: when `platform` is `win32`, line terminations are
+  CR+LF, for other platforms line termination is LF.  By default the
+  current platform name is used.
 
 For backwards compatibility reasons, if a `string` options is passed
 in, then it is assumed to be the `section` value.

lib/ini.js

@@ -1,25 +1,19 @@
 const { hasOwnProperty } = Object.prototype
 
-/* istanbul ignore next */
-const eol = typeof process !== 'undefined' &&
-  process.platform === 'win32' ? '\r\n' : '\n'
-
-const encode = (obj, opt) => {
-  const children = []
-  let out = ''
-
+const encode = (obj, opt = {}) => {
   if (typeof opt === 'string') {
-    opt = {
-      section: opt,
-      whitespace: false,
-    }
-  } else {
-    opt = opt || Object.create(null)
-    opt.whitespace = opt.whitespace === true
-    opt.newline = opt.newline === true
+    opt = { section: opt }
   }
+  opt.whitespace = opt.whitespace === true
+  opt.newline = opt.newline === true
+  /* istanbul ignore next */
+  opt.platform = opt.platform || process?.platform
 
+  /* istanbul ignore next */
+  const eol = opt.platform === 'win32' ? '\r\n' : '\n'
   const separator = opt.whitespace ? ' = ' : '='
+  const children = []
+  let out = ''
 
   for (const k of Object.keys(obj)) {
     const val = obj[k]
@@ -41,11 +35,9 @@ const encode = (obj, opt) => {
   for (const k of children) {
     const nk = dotSplit(k).join('\\.')
     const section = (opt.section ? opt.section + '.' : '') + nk
-    const { whitespace, newline } = opt
     const child = encode(obj[k], {
+      ...opt,
       section,
-      whitespace,
-      newline,
     })
     if (out.length && child.length) {
       out += eol

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

@@ -133,6 +133,18 @@ value=10
 
 `
 
+exports[`test/foo.js TAP encode with platform=win32 > must match snapshot 1`] = `
+Array [
+  "[log]",
+  "type=file",
+  "",
+  "[log.level]",
+  "label=debug",
+  "value=10",
+  "",
+]
+`
+
 exports[`test/foo.js TAP encode with whitespace > must match snapshot 1`] = `
 [log]
 type = file

test/foo.js

@@ -52,3 +52,11 @@ test('encode with newline', function (t) {
   t.matchSnapshot(e)
   t.end()
 })
+
+test('encode with platform=win32', function (t) {
+  const obj = { log: { type: 'file', level: { label: 'debug', value: 10 } } }
+  const e = i.encode(obj, { platform: 'win32' })
+
+  t.matchSnapshot(e.split('\r\n'))
+  t.end()
+})