public void Execute()
{
var reactiveUI = ModuleDefinition.AssemblyReferences.Where(x => x.Name == "ReactiveUI").OrderByDescending(x => x.Version).FirstOrDefault();
if (reactiveUI == null)
{
LogInfo("Could not find assembly: ReactiveUI (" + string.Join(", ", ModuleDefinition.AssemblyReferences.Select(x => x.Name)) + ")");
return;
}
LogInfo(string.Format("{0} {1}", reactiveUI.Name, reactiveUI.Version));
var helpers = ModuleDefinition.AssemblyReferences.Where(x => x.Name == "ReactiveUI.Fody.Helpers").OrderByDescending(x => x.Version).FirstOrDefault();
if (helpers == null)
throw new Exception("Could not find assembly: ReactiveUI.Fody.Helpers (" + string.Join(", ", ModuleDefinition.AssemblyReferences.Select(x => x.Name)) + ")");
LogInfo(string.Format("{0} {1}", helpers.Name, helpers.Version));
var reactiveObject = ModuleDefinition.FindType("ReactiveUI", "ReactiveObject", reactiveUI);
// The types we will scan are subclasses of ReactiveObject
var targetTypes = ModuleDefinition.GetAllTypes().Where(x => x.BaseType != null && reactiveObject.IsAssignableFrom(x.BaseType));
var observableAsPropertyHelper = ModuleDefinition.FindType("ReactiveUI", "ObservableAsPropertyHelper`1", reactiveUI, "T");
var observableAsPropertyAttribute = ModuleDefinition.FindType("ReactiveUI.Fody.Helpers", "ObservableAsPropertyAttribute", helpers);
var observableAsPropertyHelperGetValue = ModuleDefinition.Import(observableAsPropertyHelper.Resolve().Properties.Single(x => x.Name == "Value").GetMethod);
var exceptionType = ModuleDefinition.Import(typeof(Exception));
var exceptionConstructor = ModuleDefinition.Import(exceptionType.Resolve().GetConstructors().Single(x => x.Parameters.Count == 1));
foreach (var targetType in targetTypes)
{
foreach (var property in targetType.Properties.Where(x => x.IsDefined(observableAsPropertyAttribute)).ToArray())
{
var genericObservableAsPropertyHelper = observableAsPropertyHelper.MakeGenericInstanceType(property.PropertyType);
var genericObservableAsPropertyHelperGetValue = observableAsPropertyHelperGetValue.Bind(genericObservableAsPropertyHelper);
ModuleDefinition.Import(genericObservableAsPropertyHelperGetValue);
// Declare a field to store the property value
var field = new FieldDefinition("$" + property.Name, FieldAttributes.Private, genericObservableAsPropertyHelper);
targetType.Fields.Add(field);
// It's an auto-property, so remove the generated field
if (property.SetMethod != null)
{
// Remove old field (the generated backing field for the auto property)
var oldField = (FieldReference)property.GetMethod.Body.Instructions.Where(x => x.Operand is FieldReference).Single().Operand;
var oldFieldDefinition = oldField.Resolve();
targetType.Fields.Remove(oldFieldDefinition);
// Re-implement setter to throw an exception
property.SetMethod.Body = new MethodBody(property.SetMethod);
property.SetMethod.Body.Emit(il =>
{
il.Emit(OpCodes.Ldstr, "Never call the setter of an ObservabeAsPropertyHelper property.");
il.Emit(OpCodes.Newobj, exceptionConstructor);
il.Emit(OpCodes.Throw);
il.Emit(OpCodes.Ret);
});
}
property.GetMethod.Body = new MethodBody(property.GetMethod);
property.GetMethod.Body.Emit(il =>
{
il.Emit(OpCodes.Ldarg_0); // this
il.Emit(OpCodes.Ldfld, field.BindDefinition(targetType)); // pop -> this.$PropertyName
il.Emit(OpCodes.Callvirt, genericObservableAsPropertyHelperGetValue); // pop -> this.$PropertyName.Value
il.Emit(OpCodes.Ret); // Return the value that is on the stack
});
}
}
}
public void Execute()
{
var reactiveUI = ModuleDefinition.AssemblyReferences.Where(x => x.Name == "ReactiveUI").OrderByDescending(x => x.Version).FirstOrDefault();
if (reactiveUI == null)
{
LogInfo("Could not find assembly: ReactiveUI (" + string.Join(", ", ModuleDefinition.AssemblyReferences.Select(x => x.Name)) + ")");
return;
}
LogInfo(string.Format("{0} {1}", reactiveUI.Name, reactiveUI.Version));
var helpers = ModuleDefinition.AssemblyReferences.Where(x => x.Name == "ReactiveUI.Fody.Helpers").OrderByDescending(x => x.Version).FirstOrDefault();
if (helpers == null)
throw new Exception("Could not find assembly: ReactiveUI.Fody.Helpers (" + string.Join(", ", ModuleDefinition.AssemblyReferences.Select(x => x.Name)) + ")");
LogInfo(string.Format("{0} {1}", helpers.Name, helpers.Version));
var reactiveObject = new TypeReference("ReactiveUI", "IReactiveObject", ModuleDefinition, reactiveUI);
var targetTypes = ModuleDefinition.GetAllTypes().Where(x => x.BaseType != null && reactiveObject.IsAssignableFrom(x.BaseType)).ToArray();
var reactiveObjectExtensions = new TypeReference("ReactiveUI", "IReactiveObjectExtensions", ModuleDefinition, reactiveUI).Resolve();
if (reactiveObjectExtensions == null)
throw new Exception("reactiveObjectExtensions is null");
var raiseAndSetIfChangedMethod = ModuleDefinition.Import(reactiveObjectExtensions.Methods.Single(x => x.Name == "RaiseAndSetIfChanged"));
if (raiseAndSetIfChangedMethod == null)
throw new Exception("raiseAndSetIfChangedMethod is null");
var reactiveAttribute = ModuleDefinition.FindType("ReactiveUI.Fody.Helpers", "ReactiveAttribute", helpers);
if (reactiveAttribute == null)
throw new Exception("reactiveAttribute is null");
foreach (var targetType in targetTypes)
{
foreach (var property in targetType.Properties.Where(x => x.IsDefined(reactiveAttribute)).ToArray())
{
// Declare a field to store the property value
var field = new FieldDefinition("$" + property.Name, FieldAttributes.Private, property.PropertyType);
targetType.Fields.Add(field);
// Remove old field (the generated backing field for the auto property)
var oldField = (FieldReference)property.GetMethod.Body.Instructions.Where(x => x.Operand is FieldReference).Single().Operand;
var oldFieldDefinition = oldField.Resolve();
targetType.Fields.Remove(oldFieldDefinition);
// See if there exists an initializer for the auto-property
var constructors = targetType.Methods.Where(x => x.IsConstructor);
foreach (var constructor in constructors)
{
var fieldAssignment = constructor.Body.Instructions.SingleOrDefault(x => Equals(x.Operand, oldFieldDefinition) || Equals(x.Operand, oldField));
if (fieldAssignment != null)
{
// Replace field assignment with a property set (the stack semantics are the same for both,
// so happily we don't have to manipulate the bytecode any further.)
var setterCall = constructor.Body.GetILProcessor().Create(property.SetMethod.IsVirtual ? OpCodes.Callvirt : OpCodes.Call, property.SetMethod);
constructor.Body.GetILProcessor().Replace(fieldAssignment, setterCall);
}
}
// Build out the getter which simply returns the value of the generated field
property.GetMethod.Body = new MethodBody(property.GetMethod);
property.GetMethod.Body.Emit(il =>
{
il.Emit(OpCodes.Ldarg_0); // this
il.Emit(OpCodes.Ldfld, field.BindDefinition(targetType)); // pop -> this.$PropertyName
il.Emit(OpCodes.Ret); // Return the field value that is lying on the stack
});
TypeReference genericTargetType = targetType;
if (targetType.HasGenericParameters)
{
var genericDeclaration = new GenericInstanceType(targetType);
foreach (var parameter in targetType.GenericParameters)
{
genericDeclaration.GenericArguments.Add(parameter);
}
genericTargetType = genericDeclaration;
}
var methodReference = raiseAndSetIfChangedMethod.MakeGenericMethod(genericTargetType, property.PropertyType);
// Build out the setter which fires the RaiseAndSetIfChanged method
property.SetMethod.Body = new MethodBody(property.SetMethod);
property.SetMethod.Body.Emit(il =>
{
il.Emit(OpCodes.Ldarg_0); // this
il.Emit(OpCodes.Ldarg_0); // this
il.Emit(OpCodes.Ldflda, field.BindDefinition(targetType)); // pop -> this.$PropertyName
il.Emit(OpCodes.Ldarg_1); // value
il.Emit(OpCodes.Ldstr, property.Name); // "PropertyName"
il.Emit(OpCodes.Call, methodReference); // pop * 4 -> this.RaiseAndSetIfChanged(this.$PropertyName, value, "PropertyName")
il.Emit(OpCodes.Pop); // We don't care about the result of RaiseAndSetIfChanged, so pop it off the stack (stack is now empty)
il.Emit(OpCodes.Ret); // Return out of the function
});
}
}
}