split helpers and utilities

packages/core/src/utilities/mergeAttributes.ts

@@ -0,0 +1,28 @@
+import { AnyObject } from '../types'
+
+export default function mergeAttributes(...objects: AnyObject[]) {
+  return objects
+    .filter(item => !!item)
+    .reduce((items, item) => {
+      const mergedAttributes = { ...items }
+
+      Object.entries(item).forEach(([key, value]) => {
+        const exists = mergedAttributes[key]
+
+        if (!exists) {
+          mergedAttributes[key] = value
+          return
+        }
+
+        if (key === 'class') {
+          mergedAttributes[key] = [mergedAttributes[key], value].join(' ')
+        } else if (key === 'style') {
+          mergedAttributes[key] = [mergedAttributes[key], value].join('; ')
+        } else {
+          mergedAttributes[key] = value
+        }
+      })
+
+      return mergedAttributes
+    }, {})
+}