feat: _minBy/_maxBy now supports string comparisons

Previously only number comparisons were available
NaturalCycles · Mar 5, 2024 · ecd67dc · ecd67dc
1 parent 533fda0
commit ecd67dc
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Showing 2 changed files with 10 additions and 6 deletions.
diff --git a/src/array/array.util.test.ts b/src/array/array.util.test.ts
@@ -387,6 +387,10 @@ test('_maxBy, _minBy', () => {
   )
   expect(_minByOrUndefined([{ age: 18 }, { age: 30 }], u => u.age)).toEqual({ age: 18 })
   expect(_minBy([{ age: 18 }, { age: 30 }], u => u.age)).toEqual({ age: 18 })
+
+  expect(_minBy([{ date: '2023-06-22' }, { date: '2023-06-21' }], u => u.date)).toEqual({
+    date: '2023-06-21',
+  })
 })
 
 test('_zip', () => {

diff --git a/src/array/array.util.ts b/src/array/array.util.ts
@@ -395,13 +395,13 @@ export function _max<T>(array: T[]): NonNullable<T> {
   return a.reduce((max, item) => (max >= item ? max : item))
 }
 
-export function _maxBy<T>(array: T[], mapper: Mapper<T, number | undefined>): T {
+export function _maxBy<T>(array: T[], mapper: Mapper<T, number | string | undefined>): T {
   const max = _maxByOrUndefined(array, mapper)
   if (max === undefined) throw new Error(`_maxBy returned undefined`)
   return max
 }
 
-export function _minBy<T>(array: T[], mapper: Mapper<T, number | undefined>): T {
+export function _minBy<T>(array: T[], mapper: Mapper<T, number | string | undefined>): T {
   const min = _minByOrUndefined(array, mapper)
   if (min === undefined) throw new Error(`_minBy returned undefined`)
   return min
@@ -411,11 +411,11 @@ export function _minBy<T>(array: T[], mapper: Mapper<T, number | undefined>): T
 
 export function _maxByOrUndefined<T>(
   array: T[],
-  mapper: Mapper<T, number | undefined>,
+  mapper: Mapper<T, number | string | undefined>,
 ): T | undefined {
   if (!array.length) return
   let maxItem: T | undefined
-  let max: number | undefined
+  let max: number | string | undefined
   array.forEach((item, i) => {
     const v = mapper(item, i)
     if (v !== undefined && (max === undefined || v > max)) {
@@ -429,11 +429,11 @@ export function _maxByOrUndefined<T>(
 
 export function _minByOrUndefined<T>(
   array: T[],
-  mapper: Mapper<T, number | undefined>,
+  mapper: Mapper<T, number | string | undefined>,
 ): T | undefined {
   if (!array.length) return
   let minItem: T | undefined
-  let min: number | undefined
+  let min: number | string | undefined
   array.forEach((item, i) => {
     const v = mapper(item, i)
     if (v !== undefined && (min === undefined || v < min)) {