Adding upstream version 2.5.1.

Signed-off-by: Daniel Baumann <daniel@debian.org>

search/collector/heap.go

@@ -0,0 +1,99 @@
+//  Copyright (c) 2014 Couchbase, 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 collector
+
+import (
+	"container/heap"
+
+	"github.com/blevesearch/bleve/v2/search"
+)
+
+type collectStoreHeap struct {
+	heap    search.DocumentMatchCollection
+	compare collectorCompare
+}
+
+func newStoreHeap(capacity int, compare collectorCompare) *collectStoreHeap {
+	rv := &collectStoreHeap{
+		heap:    make(search.DocumentMatchCollection, 0, capacity),
+		compare: compare,
+	}
+	heap.Init(rv)
+	return rv
+}
+
+func (c *collectStoreHeap) AddNotExceedingSize(doc *search.DocumentMatch,
+	size int) *search.DocumentMatch {
+	c.add(doc)
+	if c.Len() > size {
+		return c.removeLast()
+	}
+	return nil
+}
+
+func (c *collectStoreHeap) add(doc *search.DocumentMatch) {
+	heap.Push(c, doc)
+}
+
+func (c *collectStoreHeap) removeLast() *search.DocumentMatch {
+	return heap.Pop(c).(*search.DocumentMatch)
+}
+
+func (c *collectStoreHeap) Final(skip int, fixup collectorFixup) (search.DocumentMatchCollection, error) {
+	count := c.Len()
+	size := count - skip
+	if size <= 0 {
+		return make(search.DocumentMatchCollection, 0), nil
+	}
+	rv := make(search.DocumentMatchCollection, size)
+	for i := size - 1; i >= 0; i-- {
+		doc := heap.Pop(c).(*search.DocumentMatch)
+		rv[i] = doc
+		err := fixup(doc)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return rv, nil
+}
+
+func (c *collectStoreHeap) Internal() search.DocumentMatchCollection {
+	return c.heap
+}
+
+// heap interface implementation
+
+func (c *collectStoreHeap) Len() int {
+	return len(c.heap)
+}
+
+func (c *collectStoreHeap) Less(i, j int) bool {
+	so := c.compare(c.heap[i], c.heap[j])
+	return -so < 0
+}
+
+func (c *collectStoreHeap) Swap(i, j int) {
+	c.heap[i], c.heap[j] = c.heap[j], c.heap[i]
+}
+
+func (c *collectStoreHeap) Push(x interface{}) {
+	c.heap = append(c.heap, x.(*search.DocumentMatch))
+}
+
+func (c *collectStoreHeap) Pop() interface{} {
+	var rv *search.DocumentMatch
+	rv, c.heap = c.heap[len(c.heap)-1], c.heap[:len(c.heap)-1]
+	return rv
+}