fix: scope duplicate key tracking per section with bracketedArray=false

lib/ini.js

@@ -111,7 +111,7 @@ const decode = (str, opt = {}) => {
   //          section          |key      = value
   const re = /^\[([^\]]*)\]\s*$|^([^=]+)(=(.*))?$/i
   const lines = str.split(/[\r\n]+/g)
-  const duplicates = {}
+  let duplicates = {}
 
   for (const line of lines) {
     if (!line || line.match(/^\s*[;#]/) || line.match(/^\s*$/)) {
@@ -123,6 +123,9 @@ const decode = (str, opt = {}) => {
     }
     if (match[1] !== undefined) {
       section = unsafe(match[1])
+      // Reset duplicates counter for each new section
+      // so keys are only treated as arrays when duplicated within the same section
+      duplicates = {}
       if (section === '__proto__') {
         // not allowed
         // keep parsing the section, but don't attach it.

test/duplicate-properties.js

@@ -38,3 +38,43 @@ test('encode duplicate properties with bracketedArray=false', function (t) {
   t.matchSnapshot(e)
   t.end()
 })
+
+// Regression test for #298 - same key name across different sections
+// should NOT be treated as duplicates
+test('bracketedArray=false should scope duplicates per section', function (t) {
+  const content = `
+[section_1]
+var = 1
+
+[section_2]
+var = 2
+`
+  const d = i.decode(content, { bracketedArray: false })
+  // Both values should be scalars, not arrays, since each key appears
+  // only once within its own section
+  t.equal(d.section_1.var, '1', 'section_1.var should be a scalar')
+  t.equal(d.section_2.var, '2', 'section_2.var should be a scalar')
+  t.notOk(Array.isArray(d.section_1.var), 'section_1.var should not be an array')
+  t.notOk(Array.isArray(d.section_2.var), 'section_2.var should not be an array')
+  t.end()
+})
+
+test('bracketedArray=false still creates arrays for duplicates within same section', function (t) {
+  const content = `
+[section_1]
+var = 1
+var = 2
+var = 3
+
+[section_2]
+var = single
+`
+  const d = i.decode(content, { bracketedArray: false })
+  // section_1.var should be an array since it has duplicates within the section
+  t.ok(Array.isArray(d.section_1.var), 'section_1.var should be an array')
+  t.same(d.section_1.var, ['1', '2', '3'], 'section_1.var should have all values')
+  // section_2.var should be a scalar since it only appears once
+  t.equal(d.section_2.var, 'single', 'section_2.var should be a scalar')
+  t.notOk(Array.isArray(d.section_2.var), 'section_2.var should not be an array')
+  t.end()
+})