private void RemoveObsoleteCodeForArgumentExpression(MethodDefinition method, Collection<Instruction> instructions, TypeDefinition displayClassType)
{
// Display class is used when there are still calls to load a field from the display class
if (instructions.UsesType(displayClassType, OpCodes.Ldfld, OpCodes.Ldftn))
{
return;
}
FodyEnvironment.LogDebug($"Method '{method.GetFullName()}' no longer uses display class '{displayClassType.GetFullName()}', removing the display class from the method");
// Remove display class from container
if (method.DeclaringType.NestedTypes.Contains(displayClassType))
{
method.DeclaringType.NestedTypes.Remove(displayClassType);
}
// Remove display class - variables
for (var i = 0; i < method.Body.Variables.Count; i++)
{
var variable = method.Body.Variables[i];
if (string.Equals(variable.VariableType.Name, displayClassType.Name))
{
method.Body.Variables.RemoveAt(i--);
}
}
// Remove display class creation, can be either:
//
// Msbuild
// L_0000: newobj instance void Catel.Fody.TestAssembly.ArgumentChecksAsExpressionsClass/<>c__DisplayClass1a::.ctor()
// L_0005: stloc.0
//
// Roslyn
// L_0000: newobj instance void Catel.Fody.TestAssembly.ArgumentChecksAsExpressionsClass/<>c__DisplayClass1a::.ctor()
// L_0005: dup
for (var i = 0; i < instructions.Count; i++)
{
var innerInstruction = instructions[i];
if (innerInstruction.OpCode == OpCodes.Newobj)
{
var remove = false;
var methodReference = innerInstruction.Operand as MethodReference;
if (methodReference != null)
{
if (string.Equals(methodReference.DeclaringType.Name, displayClassType.Name))
{
remove = true;
}
}
var methodDefinition = innerInstruction.Operand as MethodDefinition;
if (methodDefinition != null)
{
if (string.Equals(methodDefinition.DeclaringType.Name, displayClassType.Name))
{
remove = true;
}
}
if (remove)
{
// Delete 2 instructions, same location since remove will move everything 1 place up
instructions.RemoveAt(i);
// Special case in .net core
if (instructions[i].OpCode == OpCodes.Dup)
{
instructions.RemoveAt(i);
}
instructions.RemoveAt(i);
}
}
}
//// Remove all assignments to the display class
//// ldarg.0
//// stfld class MyClass/<>c__DisplayClass0_0`1<!!T>::myArgument
//for (var i = 0; i < instructions.Count; i++)
//{
// var innerInstruction = instructions[i];
//}
// Remove display class allocation and assigments
// L_0014: ldloc.0 (can also be dup)
// L_0015: ldarg.3
// L_0016: stfld object Catel.Fody.TestAssembly.ArgumentChecksAsExpressionsClass/<>c__DisplayClass28::myObject3
for (var i = 0; i < instructions.Count; i++)
{
var innerInstruction = instructions[i];
if (innerInstruction.UsesType(displayClassType, OpCodes.Stfld))
{
// Remove the stfld + 2 previous operations
instructions.RemoveAt(i);
instructions.RemoveAt(i - 1);
instructions.RemoveAt(i - 2);
i -= 3;
}
}
// Remove duplicate nop instructions at the start of a method
if (instructions.Count > 0)
{
var startInstruction = instructions[0];
if (startInstruction.IsOpCode(OpCodes.Nop))
{
instructions.RemoveAt(0);
}
}
}
private void CheckTypeVisibility (TypeDefinition type)
{
// *NativeMethods types should never be visible outside the assembly
if (type.IsVisible ()) {
string msg = String.Format (CultureInfo.InvariantCulture,
"'{0}' should not be visible outside the assembly.", type.GetFullName ());
Runner.Report (type, Severity.High, Confidence.Total, msg);
}
if (CanInstantiateType (type)) {
string msg = String.Format (CultureInfo.InvariantCulture,
"'{0}' should not be static or sealed with no visible constructor.", type.GetFullName ());
Runner.Report (type, Severity.High, Confidence.Total, msg);
}
}
public RuleResult CheckType (TypeDefinition type)
{
// rule does not apply to enums, delegates and to generated code
if (type.IsEnum || type.IsDelegate () || type.IsGeneratedCode ())
return RuleResult.DoesNotApply;
// rule applies only if the type overrides Equals(object)
if (!type.HasMethod (MethodSignatures.Equals))
return RuleResult.DoesNotApply;
// if so then the type should also implement Equals(type) since this avoid a cast
// operation (for reference types) and also boxing (for value types).
// we suggest to implement IEquatable<T> if
// * the assembly targets the 2.0 (or later) runtime
// * and it does not already implement it
if (type.Module.Runtime >= TargetRuntime.Net_2_0) {
if (!type.Implements ("System", "IEquatable`1")) {
Runner.Report (type, Severity.Medium, Confidence.Total, "Implement System.IEquatable<T>");
}
return Runner.CurrentRuleResult;
}
parameters [0] = type.GetFullName ();
if (type.GetMethod (MethodAttributes.Public, "Equals", "System.Boolean", parameters) != null)
return RuleResult.Success;
// we consider this a step more severe for value types since it will need
// boxing/unboxing with Equals(object)
Severity severity = type.IsValueType ? Severity.Medium : Severity.Low;
string msg = String.Format (CultureInfo.InvariantCulture, "Implement 'bool Equals({0})'", type.Name);
Runner.Report (type, severity, Confidence.High, msg);
return RuleResult.Failure;
}
