/// <summary>
/// Returns the strictest ExpressionCreationConditions union from the two values.
/// </summary>
/// <param name="val1">The first value.</param>
/// <param name="val2">The second value.</param>
/// <returns>Strictest ExpressionCreationConditions made from two values.</returns>
internal static ExpressionCreationConditions StrictestUnion(ExpressionCreationConditions val1, ExpressionCreationConditions val2)
{
var min = new ExpressionCreationConditions(maxDepth: Math.Min(val1.MaxDepth, val2.MaxDepth)) {
RequestedReturnType = val1.RequestedReturnType ?? val2.RequestedReturnType
};
return min;
}
/// <summary>
/// Determines whether this instance can create an object of the specified type.
/// </summary>
/// <param name="conditions">The conditions of expression evaluation when creating expression.</param>
/// <param name="context">The context of expression evaluation when creating expression.</param>
/// <returns>
/// <c>true</c> if this instance an object of the specified type; otherwise, <c>false</c>.
/// </returns>
public bool CanCreate(ExpressionCreationConditions conditions, ExpressionCreationContext context)
{
if (context == null) {
throw new ArgumentNullException("context");
}
return this.CanCreateInternal(context.RequestedReturnType);
}
/// <summary>
/// Creates a new the expression with specific expression type.
/// </summary>
/// <param name="requestedType">The requested type of the root expression.</param>
/// <param name="creationConditions">The creation conditions.</param>
/// <param name="creationContext">The context of the creation evaluation.</param>
/// <returns>New random expression.</returns>
private Expression NewExpressionInternal(ExpressionType requestedType, ExpressionCreationConditions creationConditions, ExpressionCreationContext creationContext)
{
ExpressionCreationConditions strictest = ExpressionCreationConditions.StrictestUnion(this.CreationConditions, creationConditions);
Expression expression = this.ExpressionCreator.CreateInternal(requestedType, strictest, creationContext);
return expression;
}
/// <summary>
/// Creates a new random expression.
/// </summary>
/// <remarks>
/// Tries to feed all the expression types into the expresssion
/// creator until an expresssion is successfully created.
/// </remarks>
/// <param name="conditions">The creation conditions.</param>
/// <param name="creationContext">The context of the creation evaluation.</param>
/// <returns>New random expression.</returns>
private Expression NewExpression(ExpressionCreationConditions conditions, ExpressionCreationContext creationContext)
{
List<ExpressionType> failedExpressionTypes = null;
ExpressionType randomType = default(ExpressionType);
ExpressionCreationContext currentContext = creationContext.Clone();
if (currentContext.RequestedReturnType == null) {
// Our current expression context requested type is the builder's requested type.
currentContext.RequestedReturnType = conditions.RequestedReturnType;
}
Expression newExpression;
// TODO: Ignore: You WERE HERE !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
for (;;) {
try {
for (;;) {
// TODO: This block will loop indefinitely unless we detect when valid expression types are exhausted.
randomType = this.NewExpressionTypeProvider.NextExpressionType();
/* If this expression type has not failed yet, try it. */
if (failedExpressionTypes == null || !failedExpressionTypes.Contains(randomType)) {
break;
}
}
newExpression = this.NewExpressionInternal(randomType, conditions, currentContext);
break;
} catch (ExpressionCreationException) {
/* If failed, try another expression type. */
if (failedExpressionTypes == null) {
failedExpressionTypes = new List<ExpressionType>();
}
failedExpressionTypes.Add(randomType);
}
}
return newExpression;
}
/// <summary>
/// Creates a new the expression with specific expression type.
/// </summary>
/// <remarks>
/// This method is really only meant for tests, so this will throw an exception if it can't succeed.
/// </remarks>
/// <param name="requestedType">The requested type of the root expression.</param>
/// <param name="creationConditions">The creation conditions.</param>
/// <returns>New random expression.</returns>
public Expression NewExpression(ExpressionType requestedType, ExpressionCreationConditions creationConditions)
{
try {
Expression result = this.NewExpressionInternal(requestedType, creationConditions, new ExpressionCreationContext());
return result;
} catch (Exception e) {
throw new ExpressionCreationException(string.Format(CultureInfo.InvariantCulture, "Expression of type {0} could not be created", requestedType), e);
}
}
private Expression CreateObjectExpression(ExpressionCreationConditions conditions, ExpressionCreationContext creationContext)
{
/* Check that we can create the object (for performance reasons), and create the object. */
if (this.NewObjectCreator.CanCreate(conditions, creationContext)) {
return Expression.Constant(this.NewObjectCreator.CreateObject(conditions, creationContext));
}
/*
* By default, return null if we can't create an object.
* There is also not way to alert the caller that this call couldn't create the object.
* Future: We could throw an exception, but the caller code could recover.
*/
return Expression.Constant(null);
}
private Expression CreateExpression(Func<Expression, Expression, Expression> expressionMethod, ExpressionCreationConditions conditions, ExpressionCreationContext creationContext)
{
Expression arg1 = this.NewExpressionCallback(conditions, creationContext);
creationContext.EvaluatedDataTypes.Add(arg1.Type);
Expression arg2 = this.NewExpressionCallback(conditions, creationContext);
return expressionMethod(arg1, arg2);
}
/// <summary>
/// Internal method that creates the expression that is of the specified expression type.
/// </summary>
/// <param name="expressionType">The expresion type to create.</param>
/// <param name="conditions">The creation conditions.</param>
/// <param name="creationContext">The context of the creation evaluation.</param>
/// <returns>Created expression type.</returns>
internal Expression CreateInternal(ExpressionType expressionType, ExpressionCreationConditions conditions, ExpressionCreationContext creationContext)
{
// If we have reached our max depth, then we can only create a depth that gaurentees 1 depth.
if (conditions.MaxDepth == creationContext.CurrentDepth) {
expressionType = ExpressionType.Constant;
}
/* Increment depth count. */
creationContext.CurrentDepth++;
try {
switch (expressionType) {
case ExpressionType.Add:
return this.CreateExpression(Expression.Add, conditions, creationContext);
////return Expression.Add(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.AddChecked:
return this.CreateExpression(Expression.AddChecked, conditions, creationContext);
////return Expression.AddChecked(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.And:
return Expression.And(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.AndAlso:
return Expression.AndAlso(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.ArrayLength:
return Expression.ArrayLength(this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.ArrayIndex:
return Expression.ArrayIndex(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.Call:
//// ////return Expression.Call(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
case ExpressionType.Coalesce:
return Expression.Coalesce(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.Conditional:
return Expression.Condition(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.Constant:
return this.CreateObjectExpression(conditions, creationContext);
////case ExpressionType.Convert:
//// ////return Expression.Convert(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
////case ExpressionType.ConvertChecked:
//// ////return Expression.ConvertChecked(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
case ExpressionType.Divide:
return Expression.Divide(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.Equal:
return Expression.Equal(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.ExclusiveOr:
return Expression.ExclusiveOr(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.GreaterThan:
return Expression.GreaterThan(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.GreaterThanOrEqual:
return Expression.GreaterThanOrEqual(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.Invoke:
return Expression.Invoke(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.Lambda:
//// ////return Expression.Lambda(this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
case ExpressionType.LeftShift:
return Expression.LeftShift(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.LessThan:
return Expression.LessThan(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.LessThanOrEqual:
return Expression.LessThanOrEqual(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.ListInit:
//// ////return Expression.ListInit(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
////case ExpressionType.MemberAccess:
//// ////return Expression.MakeMemberAccess(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
////case ExpressionType.MemberInit:
//// ////return Expression.MemberInit(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
case ExpressionType.Modulo:
return Expression.Modulo(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.Multiply:
return Expression.Multiply(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.MultiplyChecked:
return Expression.MultiplyChecked(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.Negate:
return Expression.Negate(this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.UnaryPlus:
return Expression.UnaryPlus(this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.NegateChecked:
return Expression.NegateChecked(this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.New:
//// ////return Expression.New(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
////case ExpressionType.NewArrayInit:
//// ////return Expression.NewArrayInit(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
////case ExpressionType.NewArrayBounds:
//// ////return Expression.NewArrayBounds(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
case ExpressionType.Not:
return Expression.Not(this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.NotEqual:
return Expression.NotEqual(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.Or:
return Expression.Or(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.OrElse:
return Expression.OrElse(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.Parameter:
//// ////return Expression.Parameter(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
case ExpressionType.Power:
return Expression.Power(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.Quote:
return Expression.Quote(this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.RightShift:
return Expression.RightShift(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.Subtract:
return Expression.Subtract(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.SubtractChecked:
return Expression.SubtractChecked(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.TypeAs:
//// ////return Expression.TypeAs(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
////case ExpressionType.TypeIs:
//// ////return Expression.TypeIs(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
case ExpressionType.Assign:
return Expression.Assign(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.Block:
return Expression.Block(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.DebugInfo:
//// ////return Expression.DebugInfo(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
case ExpressionType.Decrement:
return Expression.Decrement(this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.Dynamic:
//// ////return Expression.Dynamic(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
////case ExpressionType.Default:
//// ////return Expression.Default(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
////case ExpressionType.Extension:
//// ////return Expression(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
////case ExpressionType.Goto:
//// ////return Expression.Goto(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
case ExpressionType.Increment:
return Expression.Increment(this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.Index:
//// ////return Expression.MakeIndex(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
////case ExpressionType.Label:
//// ////return Expression.Label(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
////case ExpressionType.RuntimeVariables:
//// ////return Expression.RuntimeVariables(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
case ExpressionType.Loop:
return Expression.Loop(this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.Switch:
return Expression.Switch(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.Throw:
return Expression.Throw(this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.Try:
//// ////return Expression.MakeTry(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
////case ExpressionType.Unbox:
//// ////return Expression.Unbox(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
////case ExpressionType.AddAssign:
//// return Expression.AddAssign(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.AndAssign:
//// return Expression.AndAssign(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.DivideAssign:
//// return Expression.DivideAssign(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.ExclusiveOrAssign:
//// return Expression.ExclusiveOrAssign(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.LeftShiftAssign:
//// return Expression.LeftShiftAssign(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.ModuloAssign:
//// return Expression.ModuloAssign(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.MultiplyAssign:
//// return Expression.MultiplyAssign(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.OrAssign:
//// return Expression.OrAssign(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.PowerAssign:
//// return Expression.PowerAssign(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.RightShiftAssign:
//// return Expression.RightShiftAssign(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.SubtractAssign:
//// return Expression.SubtractAssign(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.AddAssignChecked:
//// return Expression.AddAssignChecked(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.MultiplyAssignChecked:
//// return Expression.MultiplyAssignChecked(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.SubtractAssignChecked:
//// return Expression.SubtractAssignChecked(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.PreIncrementAssign:
//// return Expression.PreIncrementAssign(this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.PreDecrementAssign:
//// return Expression.PreDecrementAssign(this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.PostIncrementAssign:
//// return Expression.PostIncrementAssign(this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.PostDecrementAssign:
//// return Expression.PostDecrementAssign(this.NewExpressionCallback(conditions, creationContext));
////case ExpressionType.TypeEqual:
//// ////return Expression.TypeEqual(this.NewExpressionCallback(conditions, creationContext), this.NewExpressionCallback(conditions, creationContext));
//// throw new NotImplementedException();
case ExpressionType.OnesComplement:
return Expression.OnesComplement(this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.IsTrue:
return Expression.IsTrue(this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.IsFalse:
return Expression.IsFalse(this.NewExpressionCallback(conditions, creationContext));
case ExpressionType.Call:
case ExpressionType.Convert:
case ExpressionType.ConvertChecked:
case ExpressionType.Lambda:
case ExpressionType.ListInit:
case ExpressionType.MemberAccess:
case ExpressionType.MemberInit:
case ExpressionType.New:
case ExpressionType.NewArrayInit:
case ExpressionType.NewArrayBounds:
case ExpressionType.Parameter:
case ExpressionType.TypeAs:
case ExpressionType.TypeIs:
case ExpressionType.DebugInfo:
case ExpressionType.Dynamic:
case ExpressionType.Default:
case ExpressionType.Extension:
case ExpressionType.Goto:
case ExpressionType.Index:
case ExpressionType.Label:
case ExpressionType.RuntimeVariables:
case ExpressionType.Try:
case ExpressionType.Unbox:
case ExpressionType.AddAssign:
case ExpressionType.AndAssign:
case ExpressionType.DivideAssign:
case ExpressionType.ExclusiveOrAssign:
case ExpressionType.LeftShiftAssign:
case ExpressionType.ModuloAssign:
case ExpressionType.MultiplyAssign:
case ExpressionType.OrAssign:
case ExpressionType.PowerAssign:
case ExpressionType.RightShiftAssign:
case ExpressionType.SubtractAssign:
case ExpressionType.AddAssignChecked:
case ExpressionType.MultiplyAssignChecked:
case ExpressionType.SubtractAssignChecked:
case ExpressionType.PreIncrementAssign:
case ExpressionType.PreDecrementAssign:
case ExpressionType.PostIncrementAssign:
case ExpressionType.PostDecrementAssign:
case ExpressionType.TypeEqual:
// Fine.
default:
throw new InvalidOperationException();
}
} catch (Exception e) {
throw new ExpressionCreationException(string.Format(CultureInfo.InvariantCulture, "Expression of type {0} could not be created", expressionType), e);
}
}
/// <summary>
/// Creates the object of the specified type.
/// </summary>
/// <param name="conditions">The conditions of expression evaluation when creating expression.</param>
/// <param name="context">The context of expression evaluation when creating expression.</param>
/// <returns>Object of type.</returns>
public object CreateObject(ExpressionCreationConditions conditions, ExpressionCreationContext context)
{
if (conditions == null) {
throw new ArgumentNullException("conditions");
}
if (context == null) {
throw new ArgumentNullException("context");
}
if (context.RequestedReturnType == null) {
throw new ArgumentException("context");
}
if (!this.TypeRepository.HasType(context.RequestedReturnType)) {
throw new ObjectCreationException();
}
foreach (MethodInfo method in this.TypeRepository.GetMethods(context.RequestedReturnType)) {
ParameterInfo[] parameters = method.GetParameters();
Func<object> callableAction = null;
if (parameters.Length == 0) {
callableAction = () => {
return method.Invoke(null, null);
};
} else if (conditions.MaxDepth > context.CurrentDepth) {
bool methodCreatable = true;
foreach (ParameterInfo parameter in parameters) {
if (!this.CanCreateInternal(parameter.ParameterType)) {
methodCreatable = false;
break;
}
}
if (methodCreatable) {
callableAction = () => {
object[] parameterObjects = new object[parameters.Length];
for (int i = 0; i < parameters.Length; i++) {
var evaluationContext = context.Clone();
evaluationContext.CurrentDepth++;
evaluationContext.RequestedReturnType = parameters[i].ParameterType;
parameterObjects[i] = this.CreateObject(conditions, evaluationContext);
}
return method.Invoke(null, parameterObjects);
};
}
}
if (callableAction != null) {
try {
/* Try to call method and return the result. */
object result = callableAction();
return result;
} catch (Exception ex) {
if (ex is TargetInvocationException || ex is ObjectCreationException) {
/* Add to our list of exceptions and continue looking for next. */
context.EvaluationExceptions.Add(ex);
continue;
} else {
// TODO
throw;
}
}
}
}
throw new ObjectCreationException();
}
