From 9df37d3c43083daa9786bc43ffc59128f9abd6cb Mon Sep 17 00:00:00 2001
From: gonzaloriestra <14979109+gonzaloriestra@users.noreply.github.com>
Date: Mon, 18 May 2026 00:26:54 +0000
Subject: [PATCH] [Performance] Optimize getArrayContainsDuplicates with early
 exit

Optimized the `getArrayContainsDuplicates` utility in `@shopify/cli-kit`
to return early as soon as the first duplicate is found.
The previous implementation always constructed a full `Set` from the entire array,
which resulted in O(n) time and memory overhead even when a duplicate was present at the beginning.

New behavior:
- Time complexity: O(k) where k is the index of the first duplicate.
- Memory complexity: O(k) for the tracking Set.
---
 .jules/bolt.md                                |  0
 .../cli-kit/src/public/common/array.test.ts   | 37 ++++++++++++++++++-
 packages/cli-kit/src/public/common/array.ts   | 13 ++++++-
 3 files changed, 48 insertions(+), 2 deletions(-)
 create mode 100644 .jules/bolt.md

diff --git a/.jules/bolt.md b/.jules/bolt.md
new file mode 100644
index 00000000000..e69de29bb2d
diff --git a/packages/cli-kit/src/public/common/array.test.ts b/packages/cli-kit/src/public/common/array.test.ts
index 720becbac0b..452259e765e 100644
--- a/packages/cli-kit/src/public/common/array.test.ts
+++ b/packages/cli-kit/src/public/common/array.test.ts
@@ -1,4 +1,4 @@
-import {difference, uniq, uniqBy} from './array.js'
+import {difference, getArrayContainsDuplicates, uniq, uniqBy} from './array.js'
 import {describe, test, expect} from 'vitest'
 
 describe('uniqBy', () => {
@@ -62,3 +62,38 @@ describe('difference', () => {
     expect(got).toEqual([1])
   })
 })
+
+describe('getArrayContainsDuplicates', () => {
+  test('returns true if the array contains duplicates', () => {
+    // Given
+    const array = [1, 2, 2, 3]
+
+    // When
+    const got = getArrayContainsDuplicates(array)
+
+    // Then
+    expect(got).toBe(true)
+  })
+
+  test('returns false if the array does not contain duplicates', () => {
+    // Given
+    const array = [1, 2, 3]
+
+    // When
+    const got = getArrayContainsDuplicates(array)
+
+    // Then
+    expect(got).toBe(false)
+  })
+
+  test('returns false for an empty array', () => {
+    // Given
+    const array: number[] = []
+
+    // When
+    const got = getArrayContainsDuplicates(array)
+
+    // Then
+    expect(got).toBe(false)
+  })
+})
diff --git a/packages/cli-kit/src/public/common/array.ts b/packages/cli-kit/src/public/common/array.ts
index 8b22c0b7b93..c6567c91203 100644
--- a/packages/cli-kit/src/public/common/array.ts
+++ b/packages/cli-kit/src/public/common/array.ts
@@ -25,11 +25,22 @@ export function getArrayRejectingUndefined<T>(array: (T | undefined)[]): T[] {
 /**
  * Returns true if an array contains duplicates.
  *
+ * This implementation is optimized to exit early as soon as the first duplicate
+ * is found, avoiding unnecessary processing of the rest of the array.
+ * Time complexity: O(k) where k is the index of the first duplicate, O(n) otherwise.
+ *
  * @param array - The array to check against.
  * @returns True if the array contains duplicates.
  */
 export function getArrayContainsDuplicates<T>(array: T[]): boolean {
-  return array.length !== new Set(array).size
+  const seen = new Set<T>()
+  for (const item of array) {
+    if (seen.has(item)) {
+      return true
+    }
+    seen.add(item)
+  }
+  return false
 }
 
 /**