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-rw-r--r--vendor/google.golang.org/protobuf/internal/order/range.go115
1 files changed, 115 insertions, 0 deletions
diff --git a/vendor/google.golang.org/protobuf/internal/order/range.go b/vendor/google.golang.org/protobuf/internal/order/range.go
new file mode 100644
index 000000000..c8090e0c5
--- /dev/null
+++ b/vendor/google.golang.org/protobuf/internal/order/range.go
@@ -0,0 +1,115 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package order provides ordered access to messages and maps.
+package order
+
+import (
+ "sort"
+ "sync"
+
+ pref "google.golang.org/protobuf/reflect/protoreflect"
+)
+
+type messageField struct {
+ fd pref.FieldDescriptor
+ v pref.Value
+}
+
+var messageFieldPool = sync.Pool{
+ New: func() interface{} { return new([]messageField) },
+}
+
+type (
+ // FieldRnger is an interface for visiting all fields in a message.
+ // The protoreflect.Message type implements this interface.
+ FieldRanger interface{ Range(VisitField) }
+ // VisitField is called everytime a message field is visited.
+ VisitField = func(pref.FieldDescriptor, pref.Value) bool
+)
+
+// RangeFields iterates over the fields of fs according to the specified order.
+func RangeFields(fs FieldRanger, less FieldOrder, fn VisitField) {
+ if less == nil {
+ fs.Range(fn)
+ return
+ }
+
+ // Obtain a pre-allocated scratch buffer.
+ p := messageFieldPool.Get().(*[]messageField)
+ fields := (*p)[:0]
+ defer func() {
+ if cap(fields) < 1024 {
+ *p = fields
+ messageFieldPool.Put(p)
+ }
+ }()
+
+ // Collect all fields in the message and sort them.
+ fs.Range(func(fd pref.FieldDescriptor, v pref.Value) bool {
+ fields = append(fields, messageField{fd, v})
+ return true
+ })
+ sort.Slice(fields, func(i, j int) bool {
+ return less(fields[i].fd, fields[j].fd)
+ })
+
+ // Visit the fields in the specified ordering.
+ for _, f := range fields {
+ if !fn(f.fd, f.v) {
+ return
+ }
+ }
+}
+
+type mapEntry struct {
+ k pref.MapKey
+ v pref.Value
+}
+
+var mapEntryPool = sync.Pool{
+ New: func() interface{} { return new([]mapEntry) },
+}
+
+type (
+ // EntryRanger is an interface for visiting all fields in a message.
+ // The protoreflect.Map type implements this interface.
+ EntryRanger interface{ Range(VisitEntry) }
+ // VisitEntry is called everytime a map entry is visited.
+ VisitEntry = func(pref.MapKey, pref.Value) bool
+)
+
+// RangeEntries iterates over the entries of es according to the specified order.
+func RangeEntries(es EntryRanger, less KeyOrder, fn VisitEntry) {
+ if less == nil {
+ es.Range(fn)
+ return
+ }
+
+ // Obtain a pre-allocated scratch buffer.
+ p := mapEntryPool.Get().(*[]mapEntry)
+ entries := (*p)[:0]
+ defer func() {
+ if cap(entries) < 1024 {
+ *p = entries
+ mapEntryPool.Put(p)
+ }
+ }()
+
+ // Collect all entries in the map and sort them.
+ es.Range(func(k pref.MapKey, v pref.Value) bool {
+ entries = append(entries, mapEntry{k, v})
+ return true
+ })
+ sort.Slice(entries, func(i, j int) bool {
+ return less(entries[i].k, entries[j].k)
+ })
+
+ // Visit the entries in the specified ordering.
+ for _, e := range entries {
+ if !fn(e.k, e.v) {
+ return
+ }
+ }
+}