fix(utils): [objectify] return type

Signed-off-by: Lexus Drumgold <[email protected]>

src/utils/__tests__/objectify.spec-d.ts

@@ -7,12 +7,12 @@ import type Vehicle from '#fixtures/types/vehicle'
 import type testSubject from '../objectify'
 
 describe('unit-d:utils/objectify', () => {
-  it('should return { [H in K]?: V }', () => {
+  it('should return { [H in K]: V }', () => {
     // Arrange
     type T = readonly [Vehicle, Vehicle]
     type K = number
     type V = Vehicle
-    type Expect = { [H in K]?: V }
+    type Expect = { [H in K]: V }
 
     // Expect
     expectTypeOf<typeof testSubject<T, K, V>>().returns.toEqualTypeOf<Expect>()

src/utils/objectify.ts

@@ -8,7 +8,7 @@ import cast from './cast'
 import define from './define'
 
 /**
- * Converts an array to a plain object.
+ * Convert an array to a plain object.
  *
  * @see {@linkcode Mapper}
  *
@@ -21,7 +21,7 @@ import define from './define'
  * @param {T} arr - Array to convert
  * @param {Mapper<T, K>} [key=(_,index)=>index] - Object key function
  * @param {Mapper<T, V>} [value=item=>item] - Object value function
- * @return {Partial<Record<K, V>>} New plain object
+ * @return {Record<K, V>} New plain object
  */
 const objectify = <
   T extends readonly unknown[],
@@ -31,10 +31,10 @@ const objectify = <
   arr: T,
   key: Mapper<T, K> = (_, index) => cast(index),
   value: Mapper<T, V> = item => cast(item)
-): { [H in K]?: V } => {
-  return arr.reduce<{ [H in K]?: V }>((acc, item, i) => {
+): { [H in K]: V } => {
+  return arr.reduce<{ [H in K]: V }>((acc, item, i) => {
     return define(acc, key(item, i, arr), { value: value(item, i, arr) })
-  }, {})
+  }, cast({}))
 }
 
 export default objectify