public void ExpressionParameterRemapperLinqToObjectsTest1()
{
//which id's to fetch
const int FirstExpressionIdToFetch = 1;
const int SecondExpressionIdToFetch = 2;
//let's create 2 expressions
Expression<Func<DummyObject, bool>> Expression1 = x => x.Id == FirstExpressionIdToFetch;
//create the 2nd expression
Expression<Func<DummyObject, bool>> Expression2 = x => x.Id == SecondExpressionIdToFetch;
//we are going to merge the 2nd expression into the first one...the main goal of the expression visitor is to reset the ParameterExpression so x => is the same x
var SecondExpressionRemappedParameters = new ExpressionParameterRemapper(Expression1.Parameters, Expression2.Parameters).Visit(Expression2.Body);
//so now we should be able to combine the expressions
var CombinedExpression = Expression.OrElse(Expression1.Body, SecondExpressionRemappedParameters);
//i should be able to run this now
Func<DummyObject, bool> CombinedExpressionInFunc = Expression.Lambda<Func<DummyObject, bool>>(CombinedExpression, Expression1.Parameters).Compile();
//let's go run the function
var ResultsOfLinqToObject = DummyObject.CreateDummyListLazy(5).Where(CombinedExpressionInFunc).ToArray();
//check the results now
Assert.Equal(2, ResultsOfLinqToObject.Length);
//make sure we have the first item
Assert.True(ResultsOfLinqToObject.Any(x => x.Id == FirstExpressionIdToFetch));
//make sure we have the 2nd item
Assert.True(ResultsOfLinqToObject.Any(x => x.Id == SecondExpressionIdToFetch));
}
public void ExpressionParameterRemapperEntityFrameworkTest1()
{
DataProviderSetupTearDown.TearDownAndBuildUpDbEnvironment();
using (var DP = DIUnitTestContainer.DIContainer.Resolve<EntityFrameworkDP<EntityFrameworkEntityDP>>(EntityFrameworkTest.ReadonlyDataProviderName))
{
//which id's to fetch
const int FirstExpressionIdToFetch = 1;
const int SecondExpressionIdToFetch = 2;
//let's create 2 expressions
Expression<Func<Ref_Test, bool>> Expression1 = x => x.Id == FirstExpressionIdToFetch;
//create the 2nd expression
Expression<Func<Ref_Test, bool>> Expression2 = x => x.Id == SecondExpressionIdToFetch;
//we are going to merge the 2nd expression into the first one...the main goal of the expression visitor is to reset the ParameterExpression so x => is the same x
var SecondExpressionRemappedParameters = new ExpressionParameterRemapper(Expression1.Parameters, Expression2.Parameters).Visit(Expression2.Body);
//so now we should be able to combine the expressions
var CombinedExpression = Expression.OrElse(Expression1.Body, SecondExpressionRemappedParameters);
//i should be able to run this now
var CombinedExpressionInFunc = Expression.Lambda<Func<Ref_Test, bool>>(CombinedExpression, Expression1.Parameters);
//let's go run the function
var ResultsOfLinqToObject = DP.Fetch<Ref_Test>(false).Where(CombinedExpressionInFunc).ToArray();
//check the results now
Assert.Equal(2, ResultsOfLinqToObject.Length);
//make sure we have the first item
Assert.True(ResultsOfLinqToObject.Any(x => x.Id == FirstExpressionIdToFetch));
//make sure we have the 2nd item
Assert.True(ResultsOfLinqToObject.Any(x => x.Id == SecondExpressionIdToFetch));
}
}
