Expression tree cloner now clones nested reference types
git-svn-id: file:///srv/devel/repo-conversion/nusu@233 d2e56fa2-650e-0410-a79f-9358c0239efd
This commit is contained in:
Markus Ewald
parent
79063f59c1
commit
3267e399ee
2 changed files with 471 additions and 384 deletions
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@ -22,369 +22,455 @@ License along with this library
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using System;
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using System.Collections.Concurrent;
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using System.Reflection;
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using System.Linq.Expressions;
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using System.Collections.Generic;
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using System.Linq.Expressions;
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using System.Reflection;
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namespace Nuclex.Support.Cloning {
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/// <summary>An action that takes its arguments as references to a structure</summary>
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/// <typeparam name="TFirst">Type of the first argument to the method</typeparam>
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/// <typeparam name="TSecond">Type of the second argument to the method</typeparam>
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/// <param name="first">First argument to the method</param>
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/// <param name="second">Second argument to the method</param>
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public delegate void ReferenceAction<TFirst, TSecond>(ref TFirst first, ref TSecond second)
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where TFirst : struct
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where TSecond : struct;
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/// <summary>An action that takes its arguments as references to a structure</summary>
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/// <typeparam name="TFirst">Type of the first argument to the method</typeparam>
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/// <typeparam name="TSecond">Type of the second argument to the method</typeparam>
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/// <param name="first">First argument to the method</param>
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/// <param name="second">Second argument to the method</param>
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public delegate void ReferenceAction<TFirst, TSecond>(ref TFirst first, ref TSecond second)
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where TFirst : struct
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where TSecond : struct;
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/// <summary>
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/// Cloning factory which uses expression trees to improve performance when cloning
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/// is a high-frequency action.
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/// </summary>
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public class ExpressionTreeCloner : ICloneFactory {
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/// <summary>
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/// Cloning factory which uses expression trees to improve performance when cloning
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/// is a high-frequency action.
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/// </summary>
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public class ExpressionTreeCloner : ICloneFactory {
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/// <summary>Initializes the static members of the expression tree cloner</summary>
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static ExpressionTreeCloner() {
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shallowCloners = new ConcurrentDictionary<Type, Delegate>();
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deepCloners = new ConcurrentDictionary<Type, Delegate>();
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}
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/// <summary>Initializes the static members of the expression tree cloner</summary>
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static ExpressionTreeCloner() {
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shallowCloners = new ConcurrentDictionary<Type, Func<object, object>>();
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deepCloners = new ConcurrentDictionary<Type, Func<object, object>>();
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}
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/// <summary>
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/// Creates a deep clone of the specified object, also creating clones of all
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/// child objects being referenced
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/// </summary>
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/// <typeparam name="TCloned">Type of the object that will be cloned</typeparam>
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/// <param name="objectToClone">Object that will be cloned</param>
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/// <param name="usePropertyBasedClone">
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/// Whether to clone the object based on its properties only
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/// </param>
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/// <returns>A deep clone of the provided object</returns>
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public static TCloned DeepClone<TCloned>(
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TCloned objectToClone, bool usePropertyBasedClone
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) {
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if(usePropertyBasedClone) {
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throw new NotImplementedException("Not implemented yet");
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} else {
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Func<TCloned, TCloned> cloner = getOrCreateDeepFieldBasedCloner<TCloned>();
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return cloner(objectToClone);
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}
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}
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/// <summary>
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/// Creates a deep clone of the specified object, also creating clones of all
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/// child objects being referenced
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/// </summary>
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/// <typeparam name="TCloned">Type of the object that will be cloned</typeparam>
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/// <param name="objectToClone">Object that will be cloned</param>
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/// <param name="usePropertyBasedClone">
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/// Whether to clone the object based on its properties only
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/// </param>
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/// <returns>A deep clone of the provided object</returns>
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public static TCloned DeepClone<TCloned>(
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TCloned objectToClone, bool usePropertyBasedClone
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) {
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object objectToCloneAsObject = objectToClone;
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if(objectToCloneAsObject == null) {
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return default(TCloned);
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}
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/// <summary>
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/// Creates a shallow clone of the specified object, reusing any referenced objects
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/// </summary>
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/// <typeparam name="TCloned">Type of the object that will be cloned</typeparam>
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/// <param name="objectToClone">Object that will be cloned</param>
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/// <param name="usePropertyBasedClone">
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/// Whether to clone the object based on its properties only
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/// </param>
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/// <returns>A shallow clone of the provided object</returns>
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public static TCloned ShallowClone<TCloned>(
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TCloned objectToClone, bool usePropertyBasedClone
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) {
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throw new NotImplementedException("Not implemented yet");
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}
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if(usePropertyBasedClone) {
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throw new NotImplementedException("Not implemented yet");
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} else {
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Func<object, object> cloner = getOrCreateDeepFieldBasedCloner(typeof(TCloned));
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return (TCloned)cloner(objectToCloneAsObject);
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}
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}
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/// <summary>
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/// Creates a deep clone of the specified object, also creating clones of all
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/// child objects being referenced
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/// </summary>
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/// <typeparam name="TCloned">Type of the object that will be cloned</typeparam>
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/// <param name="objectToClone">Object that will be cloned</param>
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/// <param name="usePropertyBasedClone">
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/// Whether to clone the object based on its properties only
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/// </param>
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/// <returns>A deep clone of the provided object</returns>
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TCloned ICloneFactory.DeepClone<TCloned>(
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TCloned objectToClone, bool usePropertyBasedClone
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) {
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return ExpressionTreeCloner.DeepClone<TCloned>(objectToClone, usePropertyBasedClone);
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}
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/// <summary>
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/// Creates a shallow clone of the specified object, reusing any referenced objects
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/// </summary>
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/// <typeparam name="TCloned">Type of the object that will be cloned</typeparam>
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/// <param name="objectToClone">Object that will be cloned</param>
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/// <param name="usePropertyBasedClone">
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/// Whether to clone the object based on its properties only
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/// </param>
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/// <returns>A shallow clone of the provided object</returns>
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public static TCloned ShallowClone<TCloned>(
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TCloned objectToClone, bool usePropertyBasedClone
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) {
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throw new NotImplementedException("Not implemented yet");
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}
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/// <summary>
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/// Creates a shallow clone of the specified object, reusing any referenced objects
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/// </summary>
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/// <typeparam name="TCloned">Type of the object that will be cloned</typeparam>
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/// <param name="objectToClone">Object that will be cloned</param>
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/// <param name="usePropertyBasedClone">
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/// Whether to clone the object based on its properties only
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/// </param>
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/// <returns>A shallow clone of the provided object</returns>
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TCloned ICloneFactory.ShallowClone<TCloned>(
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TCloned objectToClone, bool usePropertyBasedClone
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) {
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return ExpressionTreeCloner.ShallowClone<TCloned>(objectToClone, usePropertyBasedClone);
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}
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/// <summary>
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/// Creates a deep clone of the specified object, also creating clones of all
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/// child objects being referenced
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/// </summary>
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/// <typeparam name="TCloned">Type of the object that will be cloned</typeparam>
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/// <param name="objectToClone">Object that will be cloned</param>
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/// <param name="usePropertyBasedClone">
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/// Whether to clone the object based on its properties only
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/// </param>
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/// <returns>A deep clone of the provided object</returns>
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TCloned ICloneFactory.DeepClone<TCloned>(
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TCloned objectToClone, bool usePropertyBasedClone
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) {
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return ExpressionTreeCloner.DeepClone<TCloned>(objectToClone, usePropertyBasedClone);
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}
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/// <summary>
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/// Retrieves the existing clone method for the specified type or compiles one if
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/// none exists for the type yet
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/// </summary>
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/// <typeparam name="TCloned">Type for which a clone method will be retrieved</typeparam>
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/// <returns>The clone method for the specified type</returns>
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private static Func<TCloned, TCloned> getOrCreateDeepFieldBasedCloner<TCloned>() {
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Type clonedType = typeof(TCloned);
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Delegate clonerAsDelegate;
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if(deepCloners.TryGetValue(clonedType, out clonerAsDelegate)) {
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return (Func<TCloned, TCloned>)clonerAsDelegate;
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} else {
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Func<TCloned, TCloned> cloner = createDeepFieldBasedCloner<TCloned>();
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deepCloners.TryAdd(clonedType, cloner);
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return cloner;
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}
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}
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/// <summary>
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/// Creates a shallow clone of the specified object, reusing any referenced objects
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/// </summary>
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/// <typeparam name="TCloned">Type of the object that will be cloned</typeparam>
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/// <param name="objectToClone">Object that will be cloned</param>
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/// <param name="usePropertyBasedClone">
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/// Whether to clone the object based on its properties only
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/// </param>
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/// <returns>A shallow clone of the provided object</returns>
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TCloned ICloneFactory.ShallowClone<TCloned>(
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TCloned objectToClone, bool usePropertyBasedClone
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) {
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return ExpressionTreeCloner.ShallowClone<TCloned>(objectToClone, usePropertyBasedClone);
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}
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/// <summary>
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/// Generates state transfer expressions to copy an array of primitive types
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/// </summary>
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/// <param name="clonedType">Type of array that will be cloned</param>
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/// <param name="original">Variable expression for the original array</param>
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/// <param name="variables">Receives variables used by the transfer expressions</param>
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/// <param name="transferExpressions">Receives the generated transfer expressions</param>
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private static void generatePrimitiveArrayTransferExpressions(
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Type clonedType,
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ParameterExpression original,
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ICollection<ParameterExpression> variables,
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ICollection<Expression> transferExpressions
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) {
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// We need a temporary variable because the IfThen expression is not suitable
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// for returning values
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ParameterExpression clone = Expression.Variable(clonedType, "clone");
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variables.Add(clone);
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/// <summary>
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/// Retrieves the existing clone method for the specified type or compiles one if
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/// none exists for the type yet
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/// </summary>
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/// <param name="clonedType">Type for which a clone method will be retrieved</param>
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/// <returns>The clone method for the specified type</returns>
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private static Func<object, object> getOrCreateDeepFieldBasedCloner(Type clonedType) {
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Func<object, object> cloner;
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// If the array referenced by 'original' is not null, call Array.Clone() on it
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// and assign the result to our temporary variable
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MethodInfo arrayCloneMethodInfo = typeof(Array).GetMethod("Clone");
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transferExpressions.Add(
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Expression.IfThen(
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Expression.NotEqual(original, Expression.Constant(null)),
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Expression.Assign(
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clone,
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Expression.Convert(
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Expression.Call(original, arrayCloneMethodInfo),
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clonedType
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)
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)
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)
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);
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if(!deepCloners.TryGetValue(clonedType, out cloner)) {
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cloner = createDeepFieldBasedCloner(clonedType);
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deepCloners.TryAdd(clonedType, cloner);
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}
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// Set the return value to the temporary variable
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transferExpressions.Add(clone);
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}
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return cloner;
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}
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/// <summary>
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/// Generates state transfer expressions to copy an array of complex types
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/// </summary>
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/// <param name="clonedType">Type of array that will be cloned</param>
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/// <param name="original">Variable expression for the original array</param>
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/// <param name="variables">Receives variables used by the transfer expressions</param>
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/// <param name="transferExpressions">Receives the generated transfer expressions</param>
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private static void generateComplexArrayTransferExpressions(
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Type clonedType,
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ParameterExpression original,
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IList<ParameterExpression> variables,
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ICollection<Expression> transferExpressions
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) {
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// We need a temporary variable because the IfThen expression is not suitable
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// for returning values
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ParameterExpression clone = Expression.Variable(clonedType, "clone");
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variables.Add(clone);
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/// <summary>
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/// Generates state transfer expressions to copy an array of primitive types
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/// </summary>
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/// <param name="clonedType">Type of array that will be cloned</param>
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/// <param name="original">Variable expression for the original array</param>
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/// <param name="variables">Receives variables used by the transfer expressions</param>
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/// <param name="transferExpressions">Receives the generated transfer expressions</param>
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/// <returns>The variable holding the cloned array</returns>
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private static ParameterExpression generatePrimitiveArrayTransferExpressions(
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Type clonedType,
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Expression original,
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ICollection<ParameterExpression> variables,
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ICollection<Expression> transferExpressions
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) {
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// We need a temporary variable because the IfThen expression is not suitable
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// for returning values
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ParameterExpression clone = Expression.Variable(typeof(object));
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variables.Add(clone);
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int dimensionCount = clonedType.GetArrayRank();
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int baseVariableIndex = variables.Count;
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var arrayTransferExpressions = new List<Expression>();
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Type elementType = clonedType.GetElementType();
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// If the array referenced by 'original' is not null, call Array.Clone() on it
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// and assign the result to our temporary variable
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MethodInfo arrayCloneMethodInfo = typeof(Array).GetMethod("Clone");
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transferExpressions.Add(
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Expression.IfThen(
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Expression.NotEqual(original, Expression.Constant(null)),
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Expression.Assign(
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clone,
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Expression.Convert(
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Expression.Call(
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Expression.Convert(original, typeof(Array)), arrayCloneMethodInfo
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),
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clonedType
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)
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)
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)
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);
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// Retrieve the length of each of the array's dimensions
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MethodInfo arrayGetLengthMethodInfo = typeof(Array).GetMethod("GetLength");
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for(int index = 0; index < dimensionCount; ++index) {
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ParameterExpression length = Expression.Variable(typeof(int));
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variables.Add(length);
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arrayTransferExpressions.Add(
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Expression.Assign(
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length,
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Expression.Call(original, arrayGetLengthMethodInfo, Expression.Constant(index))
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)
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);
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}
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return clone;
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}
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// Create a new array of identical size
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switch(dimensionCount) {
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case 1: {
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MethodInfo arrayCreateInstanceMethodInfo = typeof(Array).GetMethod(
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"CreateInstance", new Type[] { typeof(Type), typeof(int) }
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);
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arrayTransferExpressions.Add(
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Expression.Assign(
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clone,
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Expression.Convert(
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Expression.Call(
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arrayCreateInstanceMethodInfo,
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Expression.Constant(elementType),
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variables[baseVariableIndex]
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),
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clonedType
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)
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)
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);
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break;
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}
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case 2: {
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MethodInfo arrayCreateInstanceMethodInfo = typeof(Array).GetMethod(
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"CreateInstance", new Type[] { typeof(Type), typeof(int), typeof(int) }
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);
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arrayTransferExpressions.Add(
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Expression.Assign(
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clone,
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Expression.Convert(
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Expression.Call(
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arrayCreateInstanceMethodInfo,
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Expression.Constant(elementType),
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variables[baseVariableIndex],
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variables[baseVariableIndex + 1]
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),
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clonedType
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)
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)
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);
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break;
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}
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case 3: {
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MethodInfo arrayCreateInstanceMethodInfo = typeof(Array).GetMethod(
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"CreateInstance", new Type[] { typeof(Type), typeof(int), typeof(int), typeof(int) }
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);
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arrayTransferExpressions.Add(
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Expression.Assign(
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clone,
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Expression.Convert(
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Expression.Call(
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arrayCreateInstanceMethodInfo,
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Expression.Constant(elementType),
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variables[baseVariableIndex],
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variables[baseVariableIndex + 1],
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variables[baseVariableIndex + 2]
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),
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clonedType
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)
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)
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);
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break;
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}
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default: {
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throw new InvalidOperationException("Unsupported array dimension count");
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}
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/// <summary>
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/// Generates state transfer expressions to copy an array of complex types
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/// </summary>
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/// <param name="clonedType">Type of array that will be cloned</param>
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/// <param name="original">Variable expression for the original array</param>
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/// <param name="variables">Receives variables used by the transfer expressions</param>
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/// <param name="transferExpressions">Receives the generated transfer expressions</param>
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/// <returns>The variable holding the cloned array</returns>
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private static ParameterExpression generateComplexArrayTransferExpressions(
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Type clonedType,
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Expression original,
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IList<ParameterExpression> variables,
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ICollection<Expression> transferExpressions
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) {
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// We need a temporary variable because the IfThen expression is not suitable
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// for returning values
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ParameterExpression clone = Expression.Variable(clonedType);
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variables.Add(clone);
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ParameterExpression typedOriginal = Expression.Variable(clonedType);
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variables.Add(typedOriginal);
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}
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transferExpressions.Add(
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Expression.Assign(typedOriginal, Expression.Convert(original, clonedType))
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);
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// Only execute the array transfer expressions if the array is not null
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transferExpressions.Add(
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Expression.IfThen(
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Expression.NotEqual(original, Expression.Constant(null)),
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Expression.Block(arrayTransferExpressions)
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)
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);
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int dimensionCount = clonedType.GetArrayRank();
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int baseVariableIndex = variables.Count;
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var arrayTransferExpressions = new List<Expression>();
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Type elementType = clonedType.GetElementType();
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// Set the return value to the temporary variable
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transferExpressions.Add(clone);
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}
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// Retrieve the length of each of the array's dimensions
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MethodInfo arrayGetLengthMethodInfo = typeof(Array).GetMethod("GetLength");
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for(int index = 0; index < dimensionCount; ++index) {
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ParameterExpression length = Expression.Variable(typeof(int));
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variables.Add(length);
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arrayTransferExpressions.Add(
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Expression.Assign(
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length,
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Expression.Call(
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typedOriginal, arrayGetLengthMethodInfo, Expression.Constant(index)
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)
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)
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);
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}
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|
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/// <summary>Generates state transfer expressions to copy a complex type</summary>
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/// <param name="clonedType">Complex type that will be cloned</param>
|
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/// <param name="original">Variable expression for the original instance</param>
|
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/// <param name="variables">Receives variables used by the transfer expressions</param>
|
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/// <param name="transferExpressions">Receives the generated transfer expressions</param>
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private static void generateComplexTypeTransferExpressions(
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Type clonedType,
|
||||
ParameterExpression original,
|
||||
ICollection<ParameterExpression> variables,
|
||||
ICollection<Expression> transferExpressions
|
||||
) {
|
||||
// We need a temporary variable because the IfThen expression is not suitable
|
||||
// for returning values
|
||||
ParameterExpression clone = Expression.Variable(clonedType, "clone");
|
||||
variables.Add(clone);
|
||||
// Create a new array of identical size
|
||||
switch(dimensionCount) {
|
||||
case 1: {
|
||||
MethodInfo arrayCreateInstanceMethodInfo = typeof(Array).GetMethod(
|
||||
"CreateInstance", new Type[] { typeof(Type), typeof(int) }
|
||||
);
|
||||
arrayTransferExpressions.Add(
|
||||
Expression.Assign(
|
||||
clone,
|
||||
Expression.Convert(
|
||||
Expression.Call(
|
||||
arrayCreateInstanceMethodInfo,
|
||||
Expression.Constant(elementType),
|
||||
variables[baseVariableIndex]
|
||||
),
|
||||
clonedType
|
||||
)
|
||||
)
|
||||
);
|
||||
break;
|
||||
}
|
||||
case 2: {
|
||||
MethodInfo arrayCreateInstanceMethodInfo = typeof(Array).GetMethod(
|
||||
"CreateInstance", new Type[] { typeof(Type), typeof(int), typeof(int) }
|
||||
);
|
||||
arrayTransferExpressions.Add(
|
||||
Expression.Assign(
|
||||
clone,
|
||||
Expression.Convert(
|
||||
Expression.Call(
|
||||
arrayCreateInstanceMethodInfo,
|
||||
Expression.Constant(elementType),
|
||||
variables[baseVariableIndex],
|
||||
variables[baseVariableIndex + 1]
|
||||
),
|
||||
clonedType
|
||||
)
|
||||
)
|
||||
);
|
||||
break;
|
||||
}
|
||||
case 3: {
|
||||
MethodInfo arrayCreateInstanceMethodInfo = typeof(Array).GetMethod(
|
||||
"CreateInstance", new Type[] { typeof(Type), typeof(int), typeof(int), typeof(int) }
|
||||
);
|
||||
arrayTransferExpressions.Add(
|
||||
Expression.Assign(
|
||||
clone,
|
||||
Expression.Convert(
|
||||
Expression.Call(
|
||||
arrayCreateInstanceMethodInfo,
|
||||
Expression.Constant(elementType),
|
||||
variables[baseVariableIndex],
|
||||
variables[baseVariableIndex + 1],
|
||||
variables[baseVariableIndex + 2]
|
||||
),
|
||||
clonedType
|
||||
)
|
||||
)
|
||||
);
|
||||
break;
|
||||
}
|
||||
default: {
|
||||
throw new InvalidOperationException("Unsupported array dimension count");
|
||||
}
|
||||
}
|
||||
|
||||
var complexTransferExpressions = new List<Expression>();
|
||||
|
||||
complexTransferExpressions.Add(Expression.Assign(clone, Expression.New(clonedType)));
|
||||
|
||||
FieldInfo[] fieldInfos = clonedType.GetFields(
|
||||
BindingFlags.Public | BindingFlags.NonPublic |
|
||||
BindingFlags.Instance | BindingFlags.FlattenHierarchy
|
||||
);
|
||||
for(int index = 0; index < fieldInfos.Length; ++index) {
|
||||
FieldInfo fieldInfo = fieldInfos[index];
|
||||
Type fieldType = fieldInfo.FieldType;
|
||||
// Only execute the array transfer expressions if the array is not null
|
||||
transferExpressions.Add(
|
||||
Expression.IfThen(
|
||||
Expression.NotEqual(original, Expression.Constant(null)),
|
||||
Expression.Block(arrayTransferExpressions)
|
||||
)
|
||||
);
|
||||
|
||||
if(fieldType.IsPrimitive) {
|
||||
complexTransferExpressions.Add(
|
||||
Expression.Assign(
|
||||
Expression.Field(clone, fieldInfo),
|
||||
Expression.Field(original, fieldInfo)
|
||||
)
|
||||
);
|
||||
}
|
||||
}
|
||||
return clone;
|
||||
}
|
||||
|
||||
transferExpressions.Add(
|
||||
Expression.IfThen(
|
||||
Expression.NotEqual(original, Expression.Constant(null)),
|
||||
Expression.Block(complexTransferExpressions)
|
||||
)
|
||||
);
|
||||
/// <summary>Generates state transfer expressions to copy a complex type</summary>
|
||||
/// <param name="clonedType">Complex type that will be cloned</param>
|
||||
/// <param name="original">Variable expression for the original instance</param>
|
||||
/// <param name="variables">Receives variables used by the transfer expressions</param>
|
||||
/// <param name="transferExpressions">Receives the generated transfer expressions</param>
|
||||
/// <returns>The variable holding the cloned array</returns>
|
||||
private static ParameterExpression generateComplexTypeTransferExpressions(
|
||||
Type clonedType,
|
||||
Expression original,
|
||||
IList<ParameterExpression> variables,
|
||||
ICollection<Expression> transferExpressions
|
||||
) {
|
||||
// Create a variable to hold the clone and begin by assigning a new instance of
|
||||
// the cloned type to it.
|
||||
ParameterExpression clone = Expression.Variable(clonedType);
|
||||
variables.Add(clone);
|
||||
transferExpressions.Add(Expression.Assign(clone, Expression.New(clonedType)));
|
||||
|
||||
// Set the return value to the temporary variable
|
||||
transferExpressions.Add(clone);
|
||||
}
|
||||
// To access the fields of the original type, we need it to be of the actual
|
||||
// type instead of an object, so perform a downcast
|
||||
ParameterExpression typedOriginal = Expression.Variable(clonedType);
|
||||
variables.Add(typedOriginal);
|
||||
transferExpressions.Add(
|
||||
Expression.Assign(typedOriginal, Expression.Convert(original, clonedType))
|
||||
);
|
||||
|
||||
/// <summary>Compiles a method that creates a clone of an object</summary>
|
||||
/// <typeparam name="TCloned">Type for which a clone method will be created</typeparam>
|
||||
/// <returns>A method that clones an object of the provided type</returns>
|
||||
private static Func<TCloned, TCloned> createDeepFieldBasedCloner<TCloned>() {
|
||||
Type clonedType = typeof(TCloned);
|
||||
// Now enumerate all of the type's fields and generate transfer expressions for
|
||||
// each of them
|
||||
FieldInfo[] fieldInfos = clonedType.GetFields(
|
||||
BindingFlags.Public | BindingFlags.NonPublic |
|
||||
BindingFlags.Instance | BindingFlags.FlattenHierarchy
|
||||
);
|
||||
for(int index = 0; index < fieldInfos.Length; ++index) {
|
||||
FieldInfo fieldInfo = fieldInfos[index];
|
||||
Type fieldType = fieldInfo.FieldType;
|
||||
|
||||
ParameterExpression original = Expression.Parameter(typeof(TCloned), "original");
|
||||
ParameterExpression clone = Expression.Variable(typeof(TCloned), "clone");
|
||||
if(fieldType.IsPrimitive || (fieldType == typeof(string))) {
|
||||
// Primitive types and strings can be transferred by simple assignment
|
||||
transferExpressions.Add(
|
||||
Expression.Assign(
|
||||
Expression.Field(clone, fieldInfo),
|
||||
Expression.Field(typedOriginal, fieldInfo)
|
||||
)
|
||||
);
|
||||
} else if(fieldType.IsValueType) {
|
||||
// TODO: Copy field without null check
|
||||
} else {
|
||||
var fieldTransferExpressions = new List<Expression>();
|
||||
var fieldVariables = new List<ParameterExpression>();
|
||||
|
||||
var transferExpressions = new List<Expression>();
|
||||
var variables = new List<ParameterExpression>();
|
||||
Expression fieldClone;
|
||||
if(fieldType.IsArray) {
|
||||
/*
|
||||
Type elementType = fieldType.GetElementType();
|
||||
if(elementType.IsPrimitive || (elementType == typeof(string))) {
|
||||
fieldClone = generatePrimitiveArrayTransferExpressions(
|
||||
fieldType,
|
||||
Expression.Field(typedOriginal, fieldInfo),
|
||||
fieldVariables,
|
||||
fieldTransferExpressions
|
||||
);
|
||||
} else {
|
||||
fieldClone = generateComplexArrayTransferExpressions(
|
||||
fieldType,
|
||||
Expression.Field(typedOriginal, fieldInfo),
|
||||
fieldVariables,
|
||||
fieldTransferExpressions
|
||||
);
|
||||
}
|
||||
*/
|
||||
fieldClone = Expression.Field(typedOriginal, fieldInfo);
|
||||
fieldTransferExpressions.Add(fieldClone);
|
||||
} else {
|
||||
MethodInfo getOrCreateClonerMethodInfo = typeof(ExpressionTreeCloner).GetMethod(
|
||||
"getOrCreateDeepFieldBasedCloner",
|
||||
BindingFlags.NonPublic | BindingFlags.Static
|
||||
);
|
||||
MethodInfo getTypeMethodInfo = typeof(object).GetMethod("GetType");
|
||||
MethodInfo invokeMethodInfo = typeof(Func<object, object>).GetMethod("Invoke");
|
||||
|
||||
if(clonedType.IsPrimitive || (clonedType == typeof(string))) {
|
||||
transferExpressions.Add(original); // primitives are copied on assignment
|
||||
} else if(clonedType.IsArray) {
|
||||
Type elementType = clonedType.GetElementType();
|
||||
if(elementType.IsPrimitive || (elementType == typeof(string))) {
|
||||
generatePrimitiveArrayTransferExpressions(
|
||||
clonedType, original, variables, transferExpressions
|
||||
);
|
||||
} else {
|
||||
generateComplexArrayTransferExpressions(
|
||||
clonedType, original, variables, transferExpressions
|
||||
);
|
||||
}
|
||||
} else {
|
||||
generateComplexTypeTransferExpressions(
|
||||
clonedType, original, variables, transferExpressions
|
||||
);
|
||||
}
|
||||
fieldTransferExpressions.Add(
|
||||
Expression.Assign(
|
||||
Expression.Field(clone, fieldInfo),
|
||||
Expression.Convert(
|
||||
Expression.Call(
|
||||
Expression.Call(
|
||||
getOrCreateClonerMethodInfo,
|
||||
Expression.Call(
|
||||
Expression.Field(typedOriginal, fieldInfo), getTypeMethodInfo
|
||||
)
|
||||
),
|
||||
invokeMethodInfo,
|
||||
Expression.Field(typedOriginal, fieldInfo)
|
||||
),
|
||||
fieldType
|
||||
)
|
||||
)
|
||||
);
|
||||
}
|
||||
|
||||
Expression<Func<TCloned, TCloned>> expression;
|
||||
if(variables.Count > 0) {
|
||||
expression = Expression.Lambda<Func<TCloned, TCloned>>(
|
||||
Expression.Block(variables, transferExpressions), original
|
||||
);
|
||||
} else if(transferExpressions.Count == 1) {
|
||||
expression = Expression.Lambda<Func<TCloned, TCloned>>(
|
||||
transferExpressions[0], original
|
||||
);
|
||||
} else {
|
||||
expression = Expression.Lambda<Func<TCloned, TCloned>>(
|
||||
Expression.Block(transferExpressions), original
|
||||
);
|
||||
}
|
||||
transferExpressions.Add(
|
||||
Expression.IfThen(
|
||||
Expression.NotEqual(
|
||||
Expression.Field(typedOriginal, fieldInfo), Expression.Constant(null)
|
||||
),
|
||||
Expression.Block(fieldVariables, fieldTransferExpressions)
|
||||
)
|
||||
);
|
||||
|
||||
return expression.Compile();
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return clone;
|
||||
}
|
||||
|
||||
/// <summary>Compiles a method that creates a clone of an object</summary>
|
||||
/// <param name="clonedType">Type for which a clone method will be created</param>
|
||||
/// <returns>A method that clones an object of the provided type</returns>
|
||||
private static Func<object, object> createDeepFieldBasedCloner(Type clonedType) {
|
||||
ParameterExpression original = Expression.Parameter(typeof(object), "original");
|
||||
|
||||
var transferExpressions = new List<Expression>();
|
||||
var variables = new List<ParameterExpression>();
|
||||
|
||||
if(clonedType.IsPrimitive || (clonedType == typeof(string))) {
|
||||
// Primitives and strings are copied on direct assignment
|
||||
transferExpressions.Add(original);
|
||||
} else if(clonedType.IsArray) {
|
||||
ParameterExpression clone;
|
||||
|
||||
Type elementType = clonedType.GetElementType();
|
||||
if(elementType.IsPrimitive || (elementType == typeof(string))) {
|
||||
clone = generatePrimitiveArrayTransferExpressions(
|
||||
clonedType, original, variables, transferExpressions
|
||||
);
|
||||
} else {
|
||||
clone = generateComplexArrayTransferExpressions(
|
||||
clonedType, original, variables, transferExpressions
|
||||
);
|
||||
}
|
||||
transferExpressions.Add(clone);
|
||||
|
||||
//clone = original;
|
||||
} else {
|
||||
transferExpressions.Add(
|
||||
generateComplexTypeTransferExpressions(
|
||||
clonedType, original, variables, transferExpressions
|
||||
)
|
||||
);
|
||||
}
|
||||
|
||||
Expression<Func<object, object>> expression;
|
||||
if(variables.Count > 0) {
|
||||
expression = Expression.Lambda<Func<object, object>>(
|
||||
Expression.Block(variables, transferExpressions), original
|
||||
);
|
||||
} else if(transferExpressions.Count == 1) {
|
||||
expression = Expression.Lambda<Func<object, object>>(
|
||||
transferExpressions[0], original
|
||||
);
|
||||
} else {
|
||||
expression = Expression.Lambda<Func<object, object>>(
|
||||
Expression.Block(transferExpressions), original
|
||||
);
|
||||
}
|
||||
|
||||
return expression.Compile();
|
||||
}
|
||||
|
||||
#if false
|
||||
/// <summary>
|
||||
|
|
@ -463,12 +549,12 @@ namespace Nuclex.Support.Cloning {
|
|||
}
|
||||
#endif
|
||||
|
||||
/// <summary>Compiled cloners that perform shallow clone operations</summary>
|
||||
private static ConcurrentDictionary<Type, Delegate> shallowCloners;
|
||||
/// <summary>Compiled cloners that perform deep clone operations</summary>
|
||||
private static ConcurrentDictionary<Type, Delegate> deepCloners;
|
||||
/// <summary>Compiled cloners that perform shallow clone operations</summary>
|
||||
private static ConcurrentDictionary<Type, Func<object, object>> shallowCloners;
|
||||
/// <summary>Compiled cloners that perform deep clone operations</summary>
|
||||
private static ConcurrentDictionary<Type, Func<object, object>> deepCloners;
|
||||
|
||||
}
|
||||
}
|
||||
|
||||
} // namespace Nuclex.Support.Cloning
|
||||
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue