feat: improves collection helpers (kserve#4579)

Signed-off-by: Bartosz Majsak <bartosz.majsak@gmail.com>
Co-authored-by: Sivanantham <90966311+sivanantha321@users.noreply.github.com>

Author: bartoszmajsak

pkg/utils/collections.go

@@ -0,0 +1,75 @@
+/*
+Copyright 2025 The KServe Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package utils
+
+import (
+	"strings"
+)
+
+type PredicateFn[T any] func(T) bool
+
+func FilterSlice[T any](items []T, predicate PredicateFn[T]) []T {
+	if len(items) == 0 {
+		return []T{}
+	}
+
+	result := make([]T, 0, len(items))
+	for _, item := range items {
+		if predicate(item) {
+			result = append(result, item)
+		}
+	}
+	return result
+}
+
+func Includes[T comparable](slice []T, value T) bool {
+	for _, v := range slice {
+		if v == value {
+			return true
+		}
+	}
+	return false
+}
+
+func IncludesArg(slice []string, arg string) bool {
+	for _, v := range slice {
+		if v == arg || strings.HasPrefix(v, arg) {
+			return true
+		}
+	}
+	return false
+}
+
+func Filter[K comparable, V any](origin map[K]V, predicate PredicateFn[K]) map[K]V {
+	result := make(map[K]V)
+	for k, v := range origin {
+		if predicate(k) {
+			result[k] = v
+		}
+	}
+	return result
+}
+
+func Union[K comparable, V any](maps ...map[K]V) map[K]V {
+	result := make(map[K]V)
+	for _, m := range maps {
+		for k, v := range m {
+			result[k] = v
+		}
+	}
+	return result
+}

pkg/utils/utils.go

@@ -44,44 +44,6 @@ const (
 	ErrValueExceedsInt32Limit = "value exceeds int32 limit %d"
 )
 
-func Filter(origin map[string]string, predicate func(string) bool) map[string]string {
-	result := make(map[string]string)
-	for k, v := range origin {
-		if predicate(k) {
-			result[k] = v
-		}
-	}
-	return result
-}
-
-func Union(maps ...map[string]string) map[string]string {
-	result := make(map[string]string)
-	for _, m := range maps {
-		for k, v := range m {
-			result[k] = v
-		}
-	}
-	return result
-}
-
-func Includes(slice []string, value string) bool {
-	for _, v := range slice {
-		if v == value {
-			return true
-		}
-	}
-	return false
-}
-
-func IncludesArg(slice []string, arg string) bool {
-	for _, v := range slice {
-		if v == arg || strings.HasPrefix(v, arg) {
-			return true
-		}
-	}
-	return false
-}
-
 func AppendVolumeIfNotExists(slice []corev1.Volume, volume corev1.Volume) []corev1.Volume {
 	for i := range slice {
 		if slice[i].Name == volume.Name {