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'Attempt to read protected memory' #150

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998da89
Adding failing test: 'Attempted to read or write protected memory. Th…
SteveWilkes Sep 12, 2018
24c0b63
Ignoring failing test
SteveWilkes Sep 12, 2018
a74355c
Fixing MS compiler compilation
SteveWilkes Sep 13, 2018
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127 changes: 127 additions & 0 deletions test/FastExpressionCompiler.IssueTests/IssueNew_AttemptToReadProtectedMemory.cs
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using System.Collections.Generic;
using NUnit.Framework;
#pragma warning disable 659

#if LIGHT_EXPRESSION
using static FastExpressionCompiler.LightExpression.Expression;
namespace FastExpressionCompiler.LightExpression.UnitTests
#else
using static System.Linq.Expressions.Expression;
namespace FastExpressionCompiler.UnitTests
#endif
{
using System;
using System.Linq;
using System.Reflection;

[TestFixture]
public class IssueNew_AttemptToReadProtectedMemory
{
[Test, Ignore("Fails")]
public void Nested_Assignments_Should_Work()
{
// Builds:
//
// dsosToPpssData =>
// {
// var publicPropertyStruct_String = dsosToPpssData.Target;
// string valueKey;
// object value;
// publicPropertyStruct_String.Value = ((valueKey = dsosToPpssData.Source.Keys.FirstOrDefault(key => key.MatchesKey("Value"))) != null)
// ? ((value = dsosToPpssData.Source[valueKey]) != null) ? value.ToString() : null
// : null;

// return publicPropertyStruct_String;
// }

var mappingDataParameter = Parameter(
typeof(MappingData<Dictionary<string, int>, PublicPropertyStruct<string>>),
"dsosToPpssData");

var structVariable = Variable(typeof(PublicPropertyStruct<string>), "publicPropertyStruct_String");

var structVariableAssignment = Assign(structVariable, Property(mappingDataParameter, "Target"));

var sourceDictionary = Property(mappingDataParameter, "Source");
var nullString = Default(typeof(string));
var valueKeyVariable = Variable(typeof(string), "valueKey");

var linqFirstOrDefaultMethod = typeof(Enumerable)
.GetMethods(BindingFlags.Public | BindingFlags.Static)
.First(m => m.Name == "FirstOrDefault" && m.GetParameters().Length == 2)
.MakeGenericMethod(typeof(string));

var dictionaryKeys = Property(sourceDictionary, "Keys");

var keyParameter = Parameter(typeof(string), "key");
var matchesKeyMethod = typeof(MyIssueExtensions).GetMethod("MatchesKey");
var matchesKeyCall = Call(matchesKeyMethod, keyParameter, Constant("Value"));
var matchesKeyLambda = Lambda<Func<string, bool>>(matchesKeyCall, keyParameter);

var firstOrDefaultKeyCall = Call(linqFirstOrDefaultMethod, dictionaryKeys, matchesKeyLambda);

var valueKeyAssignment = Assign(valueKeyVariable, firstOrDefaultKeyCall);
var valueKeyNotNull = NotEqual(valueKeyAssignment, nullString);

var valueVariable = Variable(typeof(object), "value");

var dictionaryIndexer = sourceDictionary.Type.GetProperties().First(p => p.GetIndexParameters().Length != 0);
var dictionaryIndexAccess = MakeIndex(sourceDictionary, dictionaryIndexer, new[] { valueKeyVariable });
var dictionaryValueAsObject = Convert(dictionaryIndexAccess, typeof(object));

var valueAssignment = Assign(valueVariable, dictionaryValueAsObject);
var valueNotNull = NotEqual(valueAssignment, Default(valueVariable.Type));

var objectToStringMethod = valueVariable.Type.GetMethod("ToString");
var valueToString = Call(valueVariable, objectToStringMethod);

var valueToStringOrNull = Condition(valueNotNull, valueToString, nullString);

var dictionaryEntryOrNull = Condition(valueKeyNotNull, valueToStringOrNull, nullString);

var structValueProperty = Property(structVariable, "Value");

var structValueAssignment = Assign(structValueProperty, dictionaryEntryOrNull);

var structPopulation = Block(
new[] { valueKeyVariable, valueVariable },
structValueAssignment);

var structMapping = Block(
new[] { structVariable },
structVariableAssignment,
structPopulation,
structVariable);

var populationLambda = Lambda<Func<MappingData<Dictionary<string, int>, PublicPropertyStruct<string>>, PublicPropertyStruct<string>>>(
structMapping,
mappingDataParameter);

var populationFunc = populationLambda.CompileFast();

// Throws 'Attempted to read or write protected memory. This is often an indication that other memory is corrupt'
populationFunc.Invoke(new MappingData<Dictionary<string, int>, PublicPropertyStruct<string>>
{
Source = new Dictionary<string, int> { ["Value"] = 123 },
Target = new PublicPropertyStruct<string>()
});
}

public class MappingData<TSource, TTarget>
{
public TSource Source { get; set; }

public TTarget Target { get; set; }
}

public struct PublicPropertyStruct<T>
{
public T Value { get; set; }
}
}

public static class MyIssueExtensions
{
public static bool MatchesKey(this string value, string other) => value == other;
}
}