chore: import upstream snapshot with attribution

utils/map_keys.go

@@ -0,0 +1,100 @@
+// Copyright 2023 Dolthub, Inc.
+//
+// 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 (
+	"cmp"
+	"sort"
+)
+
+// KeyValue represents an entry in a map.
+type KeyValue[K comparable, V any] struct {
+	Key   K
+	Value V
+}
+
+// GetMapKeys returns the map's keys as an unsorted slice.
+func GetMapKeys[K comparable, V any](m map[K]V) []K {
+	allKeys := make([]K, len(m))
+	i := 0
+	for k := range m {
+		allKeys[i] = k
+		i++
+	}
+	return allKeys
+}
+
+// GetMapKeysSorted returns the map's keys as a sorted slice. The keys are sorted in ascending order. For descending
+// order, use GetMapKeysSortedDescending.
+func GetMapKeysSorted[K cmp.Ordered, V any](m map[K]V) []K {
+	allKeys := GetMapKeys(m)
+	sort.Slice(allKeys, func(i, j int) bool {
+		return allKeys[i] < allKeys[j]
+	})
+	return allKeys
+}
+
+// GetMapKeysSortedDescending returns the map's keys as a sorted slice. The keys are sorted in descending order. For
+// ascending order, use GetMapKeysSorted.
+func GetMapKeysSortedDescending[K cmp.Ordered, V any](m map[K]V) []K {
+	allKeys := GetMapKeys(m)
+	sort.Slice(allKeys, func(i, j int) bool {
+		return allKeys[i] > allKeys[j]
+	})
+	return allKeys
+}
+
+// GetMapKVs returns the map's KeyValue entries as an unsorted slice.
+func GetMapKVs[K comparable, V any](m map[K]V) []KeyValue[K, V] {
+	allEntries := make([]KeyValue[K, V], len(m))
+	i := 0
+	for k, v := range m {
+		allEntries[i] = KeyValue[K, V]{Key: k, Value: v}
+		i++
+	}
+	return allEntries
+}
+
+// GetMapKVsSorted returns the map's KeyValue entries as a sorted slice. The keys are sorted in ascending order. For
+// descending order, use GetMapKVsSortedDescending.
+func GetMapKVsSorted[K cmp.Ordered, V any](m map[K]V) []KeyValue[K, V] {
+	allEntries := GetMapKVs(m)
+	sort.Slice(allEntries, func(i, j int) bool {
+		return allEntries[i].Key < allEntries[j].Key
+	})
+	return allEntries
+}
+
+// GetMapKVsSortedDescending returns the map's KeyValue entries as a sorted slice. The keys are sorted in descending
+// order. For ascending order, use GetMapKVsSorted.
+func GetMapKVsSortedDescending[K cmp.Ordered, V any](m map[K]V) []KeyValue[K, V] {
+	allEntries := GetMapKVs(m)
+	sort.Slice(allEntries, func(i, j int) bool {
+		return allEntries[i].Key > allEntries[j].Key
+	})
+	return allEntries
+}
+
+// GetMapValues returns the map's values as a slice. Due to Go's map iteration, the values will be in a
+// non-deterministic order.
+func GetMapValues[K comparable, V any](m map[K]V) []V {
+	allValues := make([]V, len(m))
+	i := 0
+	for _, v := range m {
+		allValues[i] = v
+		i++
+	}
+	return allValues
+}