From 260fb795d326e6b8b33a2aa7e26dc72e53a0219b Mon Sep 17 00:00:00 2001
From: dudaodong <dudaodong@gmail.com>
Date: Sat, 5 Nov 2022 16:52:31 +0800
Subject: [PATCH] feat: add KeyBy for slice

---
 slice/slice.go      | 12 ++++++++++++
 slice/slice_test.go | 10 ++++++++++
 2 files changed, 22 insertions(+)

diff --git a/slice/slice.go b/slice/slice.go
index 097925b..a9e8845 100644
--- a/slice/slice.go
+++ b/slice/slice.go
@@ -833,3 +833,15 @@ func AppendIfAbsent[T comparable](slice []T, value T) []T {
 	}
 	return slice
 }
+
+// KeyBy converts a slice to a map based on a callback function
+func KeyBy[T any, U comparable](slice []T, iteratee func(T) U) map[U]T {
+	result := make(map[U]T, len(slice))
+
+	for _, v := range slice {
+		k := iteratee(v)
+		result[k] = v
+	}
+
+	return result
+}
diff --git a/slice/slice_test.go b/slice/slice_test.go
index f7c4a08..fc3ad5d 100644
--- a/slice/slice_test.go
+++ b/slice/slice_test.go
@@ -644,3 +644,13 @@ func TestReplaceAll(t *testing.T) {
 	assert.Equal([]string{"x", "b", "x", "c", "d", "x"}, ReplaceAll(strs, "a", "x"))
 	assert.Equal([]string{"a", "b", "a", "c", "d", "a"}, ReplaceAll(strs, "e", "x"))
 }
+
+func TestKeyBy(t *testing.T) {
+	assert := internal.NewAssert(t, "TestKeyBy")
+
+	result := KeyBy([]string{"a", "ab", "abc"}, func(str string) int {
+		return len(str)
+	})
+
+	assert.Equal(result, map[int]string{1: "a", 2: "ab", 3: "abc"})
+}