From 9b6ae6d5fea407fc6cc8c8fbd93ef05db2e17946 Mon Sep 17 00:00:00 2001
From: Wojciech Maj <kontakt@wojtekmaj.pl>
Date: Mon, 30 Mar 2026 11:31:17 +0200
Subject: [PATCH] Fix accumulating spread in transform function

Spread syntax should be avoided on accumulators (like those in `.reduce`) because it causes a time complexity of `O(n^2)`.
---
 .changeset/calm-clocks-battle.md |  5 +++++
 src/index.ts                     | 15 ++++++++++-----
 2 files changed, 15 insertions(+), 5 deletions(-)
 create mode 100644 .changeset/calm-clocks-battle.md

diff --git a/.changeset/calm-clocks-battle.md b/.changeset/calm-clocks-battle.md
new file mode 100644
index 0000000..eb6c8e6
--- /dev/null
+++ b/.changeset/calm-clocks-battle.md
@@ -0,0 +1,5 @@
+---
+'css-to-react-native': patch
+---
+
+Refactor transform to avoid accumulator-based object merging.
diff --git a/src/index.ts b/src/index.ts
index dc6be3b..31c0612 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -105,15 +105,20 @@ export const getPropertyName = (propName: string): string => {
 const transform = (
   rules: StyleTuple[],
   shorthandBlacklist: string[] = []
-): Style =>
-  rules.reduce<Style>((accum, rule) => {
+): Style => {
+  const result: Style = {}
+
+  for (const rule of rules) {
     const propertyName = getPropertyName(rule[0])
     const value = rule[1]
     const allowShorthand = shorthandBlacklist.indexOf(propertyName) === -1
-    return Object.assign(
-      accum,
+    Object.assign(
+      result,
       getStylesForProperty(propertyName, value, allowShorthand)
     )
-  }, {})
+  }
+
+  return result
+}
 
 export default transform