go-bot

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// Copyright 2019 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package proto
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import (
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	"fmt"
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	"google.golang.org/protobuf/reflect/protoreflect"
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)
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// Reset clears every field in the message.
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// The resulting message shares no observable memory with its previous state
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// other than the memory for the message itself.
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func Reset(m Message) {
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	if mr, ok := m.(interface{ Reset() }); ok && hasProtoMethods {
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		mr.Reset()
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		return
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	}
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	resetMessage(m.ProtoReflect())
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}
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func resetMessage(m protoreflect.Message) {
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	if !m.IsValid() {
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		panic(fmt.Sprintf("cannot reset invalid %v message", m.Descriptor().FullName()))
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	}
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	// Clear all known fields.
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	fds := m.Descriptor().Fields()
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	for i := 0; i < fds.Len(); i++ {
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		m.Clear(fds.Get(i))
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	}
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	// Clear extension fields.
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	m.Range(func(fd protoreflect.FieldDescriptor, _ protoreflect.Value) bool {
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		m.Clear(fd)
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		return true
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	})
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	// Clear unknown fields.
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	m.SetUnknown(nil)
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}
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