92 lines
3.4 KiB
C#
92 lines
3.4 KiB
C#
// This file is part of YamlDotNet - A .NET library for YAML.
|
|
// Copyright (c) Antoine Aubry and contributors
|
|
//
|
|
// Permission is hereby granted, free of charge, to any person obtaining a copy of
|
|
// this software and associated documentation files (the "Software"), to deal in
|
|
// the Software without restriction, including without limitation the rights to
|
|
// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
|
|
// of the Software, and to permit persons to whom the Software is furnished to do
|
|
// so, subject to the following conditions:
|
|
//
|
|
// The above copyright notice and this permission notice shall be included in all
|
|
// copies or substantial portions of the Software.
|
|
//
|
|
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
|
// SOFTWARE.
|
|
|
|
using System;
|
|
using System.Collections;
|
|
using System.ComponentModel;
|
|
using YamlDotNet.Core;
|
|
|
|
namespace YamlDotNet.Serialization.ObjectGraphVisitors
|
|
{
|
|
public sealed class DefaultValuesObjectGraphVisitor : ChainedObjectGraphVisitor
|
|
{
|
|
private readonly DefaultValuesHandling handling;
|
|
|
|
public DefaultValuesObjectGraphVisitor(DefaultValuesHandling handling, IObjectGraphVisitor<IEmitter> nextVisitor)
|
|
: base(nextVisitor)
|
|
{
|
|
this.handling = handling;
|
|
}
|
|
|
|
private static object? GetDefault(Type type)
|
|
{
|
|
return type.IsValueType() ? Activator.CreateInstance(type) : null;
|
|
}
|
|
|
|
public override bool EnterMapping(IPropertyDescriptor key, IObjectDescriptor value, IEmitter context)
|
|
{
|
|
var configuration = handling;
|
|
var yamlMember = key.GetCustomAttribute<YamlMemberAttribute>();
|
|
if (yamlMember != null && yamlMember.IsDefaultValuesHandlingSpecified)
|
|
{
|
|
configuration = yamlMember.DefaultValuesHandling;
|
|
}
|
|
|
|
if ((configuration & DefaultValuesHandling.OmitNull) != 0)
|
|
{
|
|
if (value.Value is null)
|
|
{
|
|
return false;
|
|
}
|
|
}
|
|
|
|
if ((configuration & DefaultValuesHandling.OmitEmptyCollections) != 0)
|
|
{
|
|
if (value.Value is IEnumerable enumerable)
|
|
{
|
|
var enumerator = enumerable.GetEnumerator();
|
|
var canMoveNext = enumerator.MoveNext();
|
|
if (enumerator is IDisposable disposable)
|
|
{
|
|
disposable.Dispose();
|
|
}
|
|
|
|
if (!canMoveNext)
|
|
{
|
|
return false;
|
|
}
|
|
}
|
|
}
|
|
|
|
if ((configuration & DefaultValuesHandling.OmitDefaults) != 0)
|
|
{
|
|
var defaultValue = key.GetCustomAttribute<DefaultValueAttribute>()?.Value ?? GetDefault(key.Type);
|
|
if (Equals(value.Value, defaultValue))
|
|
{
|
|
return false;
|
|
}
|
|
}
|
|
|
|
return base.EnterMapping(key, value, context);
|
|
}
|
|
}
|
|
}
|