internal TypeInference(ICompilation compilation, CSharpConversions conversions)
{
Debug.Assert(compilation != null);
Debug.Assert(conversions != null);
this.compilation = compilation;
this.conversions = conversions;
}
public OverloadResolution(ICompilation compilation, ResolveResult[] arguments, string[] argumentNames = null, IType[] typeArguments = null, CSharpConversions conversions = null)
{
if (compilation == null)
{
throw new ArgumentNullException("compilation");
}
if (arguments == null)
{
throw new ArgumentNullException("arguments");
}
if (argumentNames == null)
{
argumentNames = new string[arguments.Length];
}
else if (argumentNames.Length != arguments.Length)
{
throw new ArgumentException("argumentsNames.Length must be equal to arguments.Length");
}
this.compilation = compilation;
this.arguments = arguments;
this.argumentNames = argumentNames;
// keep explicitlyGivenTypeArguments==null when no type arguments were specified
if (typeArguments != null && typeArguments.Length > 0)
{
this.explicitlyGivenTypeArguments = typeArguments;
}
this.conversions = conversions ?? CSharpConversions.Get(compilation);
this.AllowExpandingParams = true;
}
public TypeInference(ICompilation compilation)
{
if (compilation == null)
{
throw new ArgumentNullException("compilation");
}
this.compilation = compilation;
this.conversions = CSharpConversions.Get(compilation);
}
/// <summary>
/// Validates whether the given type argument satisfies the constraints for the given type parameter.
/// </summary>
/// <param name="typeParameter">The type parameter.</param>
/// <param name="typeArgument">The type argument.</param>
/// <param name="substitution">The substitution that defines how type parameters are replaced with type arguments.
/// The substitution is used to check constraints that depend on other type parameters (or recursively on the same type parameter).
/// May be null if no substitution should be used.</param>
/// <returns>True if the constraints are satisfied; false otherwise.</returns>
public static bool ValidateConstraints(ITypeParameter typeParameter, IType typeArgument, TypeVisitor substitution = null)
{
if (typeParameter == null)
{
throw new ArgumentNullException("typeParameter");
}
if (typeArgument == null)
{
throw new ArgumentNullException("typeArgument");
}
return(ValidateConstraints(typeParameter, typeArgument, substitution, CSharpConversions.Get(typeParameter.Owner.Compilation)));
}
/// <summary>
/// Gets the Conversions instance for the specified <see cref="ICompilation"/>.
/// This will make use of the context's cache manager to reuse the Conversions instance.
/// </summary>
public static CSharpConversions Get(ICompilation compilation)
{
if (compilation == null)
{
throw new ArgumentNullException("compilation");
}
CacheManager cache = compilation.CacheManager;
CSharpConversions operators = (CSharpConversions)cache.GetShared(typeof(CSharpConversions));
if (operators == null)
{
operators = (CSharpConversions)cache.GetOrAddShared(typeof(CSharpConversions), new CSharpConversions(compilation));
}
return(operators);
}
internal static bool ValidateConstraints(ITypeParameter typeParameter, IType typeArgument, TypeVisitor substitution, CSharpConversions conversions)
{
switch (typeArgument.Kind) // void, null, and pointers cannot be used as type arguments
{
case TypeKind.Void:
case TypeKind.Null:
case TypeKind.Pointer:
return(false);
}
if (typeParameter.HasReferenceTypeConstraint)
{
if (typeArgument.IsReferenceType != true)
{
return(false);
}
}
if (typeParameter.HasValueTypeConstraint)
{
if (!NullableType.IsNonNullableValueType(typeArgument))
{
return(false);
}
}
if (typeParameter.HasDefaultConstructorConstraint)
{
ITypeDefinition def = typeArgument.GetDefinition();
if (def != null && def.IsAbstract)
{
return(false);
}
var ctors = typeArgument.GetConstructors(
m => m.Parameters.Count == 0 && m.Accessibility == Accessibility.Public,
GetMemberOptions.IgnoreInheritedMembers | GetMemberOptions.ReturnMemberDefinitions
);
if (!ctors.Any())
{
return(false);
}
}
foreach (IType constraintType in typeParameter.DirectBaseTypes)
{
IType c = constraintType;
if (substitution != null)
{
c = c.AcceptVisitor(substitution);
}
if (!conversions.IsConstraintConvertible(typeArgument, c))
{
return(false);
}
}
return(true);
}
public ConstraintValidatingSubstitution(IList <IType> classTypeArguments, IList <IType> methodTypeArguments, OverloadResolution overloadResolution)
: base(classTypeArguments, methodTypeArguments)
{
this.conversions = overloadResolution.conversions;
}
public override Conversion IsValid(IType[] parameterTypes, IType returnType, CSharpConversions conversions)
{
Assert.AreEqual(expectedParameterTypes, parameterTypes);
return(conversions.ImplicitConversion(inferredReturnType, returnType));
}
public DynamicErasure(CSharpConversions conversions)
{
this.objectType = conversions.objectType;
}
public OverloadResolution PerformOverloadResolution(ICompilation compilation, ResolveResult[] arguments, string[] argumentNames = null,
bool allowExtensionMethods = true,
bool allowExpandingParams = true,
bool allowOptionalParameters = true,
bool checkForOverflow = false, CSharpConversions conversions = null)
{
Log.WriteLine("Performing overload resolution for " + this);
Log.WriteCollection(" Arguments: ", arguments);
var typeArgumentArray = this.TypeArguments.ToArray();
OverloadResolution or = new OverloadResolution(compilation, arguments, argumentNames, typeArgumentArray, conversions);
or.AllowExpandingParams = allowExpandingParams;
or.AllowOptionalParameters = allowOptionalParameters;
or.CheckForOverflow = checkForOverflow;
or.AddMethodLists(methodLists);
if (allowExtensionMethods && !or.FoundApplicableCandidate)
{
// No applicable match found, so let's try extension methods.
var extensionMethods = this.GetExtensionMethods();
if (extensionMethods.Any())
{
Log.WriteLine("No candidate is applicable, trying {0} extension methods groups...", extensionMethods.Count());
ResolveResult[] extArguments = new ResolveResult[arguments.Length + 1];
extArguments[0] = new ResolveResult(this.TargetType);
arguments.CopyTo(extArguments, 1);
string[] extArgumentNames = null;
if (argumentNames != null)
{
extArgumentNames = new string[argumentNames.Length + 1];
argumentNames.CopyTo(extArgumentNames, 1);
}
var extOr = new OverloadResolution(compilation, extArguments, extArgumentNames, typeArgumentArray, conversions);
extOr.AllowExpandingParams = allowExpandingParams;
extOr.AllowOptionalParameters = allowOptionalParameters;
extOr.IsExtensionMethodInvocation = true;
extOr.CheckForOverflow = checkForOverflow;
foreach (var g in extensionMethods)
{
foreach (var method in g)
{
Log.Indent();
OverloadResolutionErrors errors = extOr.AddCandidate(method);
Log.Unindent();
or.LogCandidateAddingResult(" Extension", method, errors);
}
if (extOr.FoundApplicableCandidate)
{
break;
}
}
// For the lack of a better comparison function (the one within OverloadResolution
// cannot be used as it depends on the argument set):
if (extOr.FoundApplicableCandidate || or.BestCandidate == null)
{
// Consider an extension method result better than the normal result only
// if it's applicable; or if there is no normal result.
or = extOr;
}
}
}
Log.WriteLine("Overload resolution finished, best candidate is {0}.", or.GetBestCandidateWithSubstitutedTypeArguments());
return(or);
}
public override Conversion IsValid(IType[] parameterTypes, IType returnType, CSharpConversions conversions)
{
return(conversions.ImplicitConversion(inferredReturnType, returnType));
}
public void SetUp()
{
compilation = new SimpleCompilation(CecilLoaderTests.Mscorlib);
conversions = new CSharpConversions(compilation);
}
/// <summary> /// Gets whether the lambda body is valid for the given parameter types and return type. /// </summary> /// <returns> /// Produces a conversion with <see cref="Conversion.IsAnonymousFunctionConversion"/>=<c>true</c> if the lambda is valid; /// otherwise returns <see cref="Conversion.None"/>. /// </returns> public abstract Conversion IsValid(IType[] parameterTypes, IType returnType, CSharpConversions conversions);
public override void SetUp()
{
base.SetUp();
conversions = new CSharpConversions(compilation);
}