feat: add newline option (#198)

Co-authored-by: Francois-Xavier Kowalski <fix@hp.com>

README.md

@@ -82,6 +82,10 @@ The `options` object may contain the following:
   `=` character.  By default, whitespace is omitted, to be friendly to
   some persnickety old parsers that don't tolerate it well.  But some
   find that it's more human-readable and pretty with the whitespace.
+* `newline` Boolean to specify whether to put an additional newline
+  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.
 
 For backwards compatibility reasons, if a `string` options is passed
 in, then it is assumed to be the `section` value.

lib/ini.js

@@ -16,6 +16,7 @@ const encode = (obj, opt) => {
   } else {
     opt = opt || Object.create(null)
     opt.whitespace = opt.whitespace === true
+    opt.newline = opt.newline === true
   }
 
   const separator = opt.whitespace ? ' = ' : '='
@@ -34,16 +35,17 @@ const encode = (obj, opt) => {
   }
 
   if (opt.section && out.length) {
-    out = '[' + safe(opt.section) + ']' + eol + out
+    out = '[' + safe(opt.section) + ']' + (opt.newline ? eol + eol : eol) + out
   }
 
   for (const k of children) {
     const nk = dotSplit(k).join('\\.')
     const section = (opt.section ? opt.section + '.' : '') + nk
-    const { whitespace } = opt
+    const { whitespace, newline } = opt
     const child = encode(obj[k], {
       section,
       whitespace,
+      newline,
     })
     if (out.length && child.length) {
       out += eol

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

@@ -110,6 +110,18 @@ noHashComment=this\\# this is not a comment
 
 `
 
+exports[`test/foo.js TAP encode with newline > must match snapshot 1`] = `
+[log]
+
+type=file
+
+[log.level]
+
+label=debug
+value=10
+
+`
+
 exports[`test/foo.js TAP encode with option > must match snapshot 1`] = `
 [prefix.log]
 type=file

test/foo.js

@@ -44,3 +44,11 @@ test('encode with whitespace', function (t) {
   t.matchSnapshot(e)
   t.end()
 })
+
+test('encode with newline', function (t) {
+  const obj = { log: { type: 'file', level: { label: 'debug', value: 10 } } }
+  const e = i.encode(obj, { newline: true })
+
+  t.matchSnapshot(e)
+  t.end()
+})