fix: use stable locale for natural sort

README.md

@@ -556,6 +556,16 @@ const values = ['1_foo_bar', '12_foo_bar'].sort(naturalSort)
 // Default sorting: ['1_foo_bar', '12_foo_bar']
 ```
 
+The default comparator uses the English locale. Use `createNaturalSort` to sort with a different locale.
+
+```ts
+import { createNaturalSort } from '@poppinss/utils'
+
+const naturalSort = createNaturalSort({ locale: 'cs' })
+const values = ['children', 'groups'].sort(naturalSort)
+// ['groups', 'children']
+```
+
 ## getGitWorktree
 
 Returns information about the linked Git worktree containing the current working directory. The method returns `null` when called from the primary worktree, outside a Git repository, or when Git is unavailable.

index.ts

@@ -12,7 +12,7 @@ export { compose } from './src/compose.js'
 export { flatten } from './src/flatten.js'
 export { unique } from './src/unique.js'
 export { safeEqual } from './src/safe_equal.js'
-export { naturalSort } from './src/natural_sort.js'
+export { naturalSort, createNaturalSort } from './src/natural_sort.js'
 export { isScriptFile } from './src/is_script_file.js'
 export { importDefault } from './src/import_default.js'
 export { MessageBuilder } from './src/message_builder.js'

src/natural_sort.ts

@@ -7,13 +7,19 @@
  * file that was distributed with this source code.
  */
 
-let collator: Intl.Collator | undefined
+/**
+ * Create a natural sort comparator for a specific locale
+ */
+export function createNaturalSort({ locale }: { locale: Intl.LocalesArgument }) {
+  let collator: Intl.Collator | undefined
+
+  return function naturalSort(current: string, next: string) {
+    collator ??= new Intl.Collator(locale, { numeric: true, sensitivity: 'base' })
+    return collator.compare(current, next)
+  }
+}
 
 /**
  * Perform natural sorting with "Array.sort()" method
  */
-export function naturalSort(current: string, next: string) {
-  // Create the collator only when natural sorting is used, not on package import.
-  collator ??= new Intl.Collator(undefined, { numeric: true, sensitivity: 'base' })
-  return collator.compare(current, next)
-}
+export const naturalSort = createNaturalSort({ locale: 'en' })

tests/natural_sort.spec.ts

@@ -8,7 +8,7 @@
  */
 
 import { test } from '@japa/runner'
-import { naturalSort } from '../src/natural_sort.js'
+import { createNaturalSort, naturalSort } from '../src/natural_sort.js'
 
 test.group('natural sort', () => {
   test('sort numbers naturally and preserve the order of equivalent strings', ({ assert }) => {
@@ -21,7 +21,7 @@ test.group('natural sort', () => {
     ])
   })
 
-  test('match localeCompare ordering for the default locale', ({ assert }) => {
+  test('match localeCompare ordering for the English locale', ({ assert }) => {
     const values = [
       '',
       'a',
@@ -47,7 +47,7 @@ test.group('natural sort', () => {
       ),
     ]
     const previous = (current: string, next: string) =>
-      current.localeCompare(next, undefined, { numeric: true, sensitivity: 'base' })
+      current.localeCompare(next, 'en', { numeric: true, sensitivity: 'base' })
 
     for (const current of values) {
       for (const next of values) {
@@ -57,4 +57,14 @@ test.group('natural sort', () => {
     assert.deepEqual([...values].sort(naturalSort), [...values].sort(previous))
     assert.deepEqual([...values].reverse().sort(naturalSort), [...values].reverse().sort(previous))
   })
+
+  test('use English ordering by default', ({ assert }) => {
+    assert.deepEqual(['groups', 'children'].sort(naturalSort), ['children', 'groups'])
+  })
+
+  test('create a comparator with an explicit locale', ({ assert }) => {
+    const czechNaturalSort = createNaturalSort({ locale: 'cs' })
+
+    assert.deepEqual(['children', 'groups'].sort(czechNaturalSort), ['groups', 'children'])
+  })
 })