1 files changed, 91 insertions, 0 deletions
diff --git a/hugolib/doctree/simpletree.go b/hugolib/doctree/simpletree.go
new file mode 100644
index 000000000..811a7ff80
--- /dev/null
+++ b/hugolib/doctree/simpletree.go
@@ -0,0 +1,91 @@
+// Copyright 2024 The Hugo Authors. All rights reserved.
+//
+// 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 doctree
+
+import (
+	"sync"
+
+	radix "github.com/armon/go-radix"
+)
+
+// Tree is a radix tree that holds T.
+type Tree[T any] interface {
+	Get(s string) T
+	LongestPrefix(s string) (string, T)
+	Insert(s string, v T) T
+	WalkPrefix(lockType LockType, s string, f func(s string, v T) (bool, error)) error
+}
+
+// NewSimpleTree creates a new SimpleTree.
+func NewSimpleTree[T any]() *SimpleTree[T] {
+	return &SimpleTree[T]{tree: radix.New()}
+}
+
+// SimpleTree is a thread safe radix tree that holds T.
+type SimpleTree[T any] struct {
+	mu   sync.RWMutex
+	tree *radix.Tree
+	zero T
+}
+
+func (tree *SimpleTree[T]) Get(s string) T {
+	tree.mu.RLock()
+	defer tree.mu.RUnlock()
+
+	if v, ok := tree.tree.Get(s); ok {
+		return v.(T)
+	}
+	return tree.zero
+}
+
+func (tree *SimpleTree[T]) LongestPrefix(s string) (string, T) {
+	tree.mu.RLock()
+	defer tree.mu.RUnlock()
+
+	if s, v, ok := tree.tree.LongestPrefix(s); ok {
+		return s, v.(T)
+	}
+	return "", tree.zero
+}
+
+func (tree *SimpleTree[T]) Insert(s string, v T) T {
+	tree.mu.Lock()
+	defer tree.mu.Unlock()
+
+	tree.tree.Insert(s, v)
+	return v
+}
+
+func (tree *SimpleTree[T]) WalkPrefix(lockType LockType, s string, f func(s string, v T) (bool, error)) error {
+	switch lockType {
+	case LockTypeNone:
+	case LockTypeRead:
+		tree.mu.RLock()
+		defer tree.mu.RUnlock()
+	case LockTypeWrite:
+		tree.mu.Lock()
+		defer tree.mu.Unlock()
+	}
+	var err error
+	tree.tree.WalkPrefix(s, func(s string, v any) bool {
+		var b bool
+		b, err = f(s, v.(T))
+		if err != nil {
+			return true
+		}
+		return b
+	})
+
+	return err
+}