podman

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// Copyright (C) MongoDB, Inc. 2017-present.
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//
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// Licensed under the Apache License, Version 2.0 (the "License"); you may
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// not use this file except in compliance with the License. You may obtain
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// a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
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package bsonrw
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import (
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	"fmt"
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)
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type mode int
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const (
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	_ mode = iota
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	mTopLevel
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	mDocument
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	mArray
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	mValue
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	mElement
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	mCodeWithScope
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	mSpacer
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)
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func (m mode) String() string {
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	var str string
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	switch m {
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	case mTopLevel:
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		str = "TopLevel"
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	case mDocument:
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		str = "DocumentMode"
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	case mArray:
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		str = "ArrayMode"
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	case mValue:
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		str = "ValueMode"
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	case mElement:
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		str = "ElementMode"
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	case mCodeWithScope:
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		str = "CodeWithScopeMode"
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	case mSpacer:
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		str = "CodeWithScopeSpacerFrame"
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	default:
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		str = "UnknownMode"
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	}
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	return str
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}
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func (m mode) TypeString() string {
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	var str string
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	switch m {
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	case mTopLevel:
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		str = "TopLevel"
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	case mDocument:
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		str = "Document"
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	case mArray:
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		str = "Array"
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	case mValue:
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		str = "Value"
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	case mElement:
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		str = "Element"
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	case mCodeWithScope:
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		str = "CodeWithScope"
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	case mSpacer:
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		str = "CodeWithScopeSpacer"
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	default:
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		str = "Unknown"
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	}
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	return str
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}
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// TransitionError is an error returned when an invalid progressing a
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// ValueReader or ValueWriter state machine occurs.
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// If read is false, the error is for writing
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type TransitionError struct {
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	name        string
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	parent      mode
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	current     mode
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	destination mode
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	modes       []mode
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	action      string
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}
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func (te TransitionError) Error() string {
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	errString := fmt.Sprintf("%s can only %s", te.name, te.action)
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	if te.destination != mode(0) {
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		errString = fmt.Sprintf("%s a %s", errString, te.destination.TypeString())
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	}
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	errString = fmt.Sprintf("%s while positioned on a", errString)
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	for ind, m := range te.modes {
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		if ind != 0 && len(te.modes) > 2 {
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			errString = fmt.Sprintf("%s,", errString)
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		}
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		if ind == len(te.modes)-1 && len(te.modes) > 1 {
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			errString = fmt.Sprintf("%s or", errString)
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		}
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		errString = fmt.Sprintf("%s %s", errString, m.TypeString())
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	}
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	errString = fmt.Sprintf("%s but is positioned on a %s", errString, te.current.TypeString())
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	if te.parent != mode(0) {
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		errString = fmt.Sprintf("%s with parent %s", errString, te.parent.TypeString())
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	}
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	return errString
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}
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