mcs/mcs/import.cs

   1 //
   2 // import.cs: System.Reflection conversions
   3 //
   4 // Authors: Marek Safar (marek.safar@gmail.com)
   5 //
   6 // Dual licensed under the terms of the MIT X11 or GNU GPL
   7 //
   8 // Copyright 2009, 2010 Novell, Inc
   9 //
  10
  11 using System;
  12 using System.Runtime.CompilerServices;
  13 using System.Linq;
  14 using System.Collections.Generic;
  15
  16 #if STATIC
  17 using MetaType = IKVM.Reflection.Type;
  18 using IKVM.Reflection;
  19 using IKVM.Reflection.Emit;
  20 #else
  21 using MetaType = System.Type;
  22 using System.Reflection;
  23 using System.Reflection.Emit;
  24 #endif
  25
  26 namespace Mono.CSharp
  27 {
  28         public abstract class MetadataImporter
  29         {
  30                 //
  31                 // Dynamic types reader with additional logic to reconstruct a dynamic
  32                 // type using DynamicAttribute values
  33                 //
  34                 struct DynamicTypeReader
  35                 {
  36                         static readonly bool[] single_attribute = { true };
  37
  38                         public int Position;
  39                         bool[] flags;
  40
  41                         // There is no common type for CustomAttributeData and we cannot
  42                         // use ICustomAttributeProvider
  43                         object provider;
  44
  45                         //
  46                         // A member provider which can be used to get CustomAttributeData
  47                         //
  48                         public DynamicTypeReader (object provider)
  49                         {
  50                                 Position = 0;
  51                                 flags = null;
  52                                 this.provider = provider;
  53                         }
  54
  55                         //
  56                         // Returns true when object at local position has dynamic attribute flag
  57                         //
  58                         public bool IsDynamicObject (MetadataImporter importer)
  59                         {
  60                                 if (provider != null)
  61                                         ReadAttribute (importer);
  62
  63                                 return flags != null && Position < flags.Length && flags[Position];
  64                         }
  65
  66                         //
  67                         // Returns true when DynamicAttribute exists
  68                         //
  69                         public bool HasDynamicAttribute (MetadataImporter importer)
  70                         {
  71                                 if (provider != null)
  72                                         ReadAttribute (importer);
  73
  74                                 return flags != null;
  75                         }
  76
  77                         void ReadAttribute (MetadataImporter importer)
  78                         {
  79                                 IList<CustomAttributeData> cad;
  80                                 if (provider is MemberInfo) {
  81                                         cad = CustomAttributeData.GetCustomAttributes ((MemberInfo) provider);
  82                                 } else if (provider is ParameterInfo) {
  83                                         cad = CustomAttributeData.GetCustomAttributes ((ParameterInfo) provider);
  84                                 } else {
  85                                         provider = null;
  86                                         return;
  87                                 }
  88
  89                                 if (cad.Count > 0) {
  90                                         string ns, name;
  91                                         foreach (var ca in cad) {
  92                                                 importer.GetCustomAttributeTypeName (ca, out ns, out name);
  93                                                 if (name != "DynamicAttribute" && ns != CompilerServicesNamespace)
  94                                                         continue;
  95
  96                                                 if (ca.ConstructorArguments.Count == 0) {
  97                                                         flags = single_attribute;
  98                                                         break;
  99                                                 }
 100
 101                                                 var arg_type = ca.ConstructorArguments[0].ArgumentType;
 102
 103                                                 if (arg_type.IsArray && MetaType.GetTypeCode (arg_type.GetElementType ()) == TypeCode.Boolean) {
 104                                                         var carg = (IList<CustomAttributeTypedArgument>) ca.ConstructorArguments[0].Value;
 105                                                         flags = new bool[carg.Count];
 106                                                         for (int i = 0; i < flags.Length; ++i) {
 107                                                                 if (MetaType.GetTypeCode (carg[i].ArgumentType) == TypeCode.Boolean)
 108                                                                         flags[i] = (bool) carg[i].Value;
 109                                                         }
 110
 111                                                         break;
 112                                                 }
 113                                         }
 114                                 }
 115
 116                                 provider = null;
 117                         }
 118                 }
 119
 120                 protected readonly Dictionary<MetaType, TypeSpec> import_cache;
 121                 protected readonly Dictionary<MetaType, TypeSpec> compiled_types;
 122                 protected readonly Dictionary<Assembly, IAssemblyDefinition> assembly_2_definition;
 123                 readonly ModuleContainer module;
 124
 125                 public static readonly string CompilerServicesNamespace = "System.Runtime.CompilerServices";
 126
 127                 protected MetadataImporter (ModuleContainer module)
 128                 {
 129                         this.module = module;
 130
 131                         import_cache = new Dictionary<MetaType, TypeSpec> (1024, ReferenceEquality<MetaType>.Default);
 132                         compiled_types = new Dictionary<MetaType, TypeSpec> (40, ReferenceEquality<MetaType>.Default);
 133                         assembly_2_definition = new Dictionary<Assembly, IAssemblyDefinition> (ReferenceEquality<Assembly>.Default);
 134                         IgnorePrivateMembers = true;
 135                 }
 136
 137                 #region Properties
 138
 139                 public ICollection<IAssemblyDefinition> Assemblies {
 140                         get {
 141                                 return assembly_2_definition.Values;
 142                         }
 143                 }
 144
 145                 public bool IgnorePrivateMembers { get; set; }
 146
 147                 #endregion
 148
 149                 public abstract void AddCompiledType (TypeBuilder builder, TypeSpec spec);
 150                 protected abstract MemberKind DetermineKindFromBaseType (MetaType baseType);
 151                 protected abstract bool HasVolatileModifier (MetaType[] modifiers);
 152                 public abstract void GetCustomAttributeTypeName (CustomAttributeData cad, out string typeNamespace, out string typeName);
 153
 154                 public FieldSpec CreateField (FieldInfo fi, TypeSpec declaringType)
 155                 {
 156                         Modifiers mod = 0;
 157                         var fa = fi.Attributes;
 158                         switch (fa & FieldAttributes.FieldAccessMask) {
 159                                 case FieldAttributes.Public:
 160                                         mod = Modifiers.PUBLIC;
 161                                         break;
 162                                 case FieldAttributes.Assembly:
 163                                         mod = Modifiers.INTERNAL;
 164                                         break;
 165                                 case FieldAttributes.Family:
 166                                         mod = Modifiers.PROTECTED;
 167                                         break;
 168                                 case FieldAttributes.FamORAssem:
 169                                         mod = Modifiers.PROTECTED | Modifiers.INTERNAL;
 170                                         break;
 171                                 default:
 172                                         // Ignore private fields (even for error reporting) to not require extra dependencies
 173                                         if (IgnorePrivateMembers || HasAttribute (CustomAttributeData.GetCustomAttributes (fi), "CompilerGeneratedAttribute", CompilerServicesNamespace))
 174                                                 return null;
 175
 176                                         mod = Modifiers.PRIVATE;
 177                                         break;
 178                         }
 179
 180                         TypeSpec field_type;
 181
 182                         try {
 183                                 field_type = ImportType (fi.FieldType, new DynamicTypeReader (fi));
 184                         } catch (Exception e) {
 185                                 // TODO: I should construct fake TypeSpec based on TypeRef signature
 186                                 // but there is no way to do it with System.Reflection
 187                                 throw new InternalErrorException (e, "Cannot import field `{0}.{1}' referenced in assembly `{2}'",
 188                                         declaringType.GetSignatureForError (), fi.Name, declaringType.MemberDefinition.DeclaringAssembly);
 189                         }
 190
 191                         var definition = new ImportedMemberDefinition (fi, field_type, this);
 192
 193                         if ((fa & FieldAttributes.Literal) != 0) {
 194                                 var c = Constant.CreateConstantFromValue (field_type, fi.GetRawConstantValue (), Location.Null);
 195                                 return new ConstSpec (declaringType, definition, field_type, fi, mod, c);
 196                         }
 197
 198                         if ((fa & FieldAttributes.InitOnly) != 0) {
 199                                 if (field_type.BuiltinType == BuiltinTypeSpec.Type.Decimal) {
 200                                         var dc = ReadDecimalConstant (CustomAttributeData.GetCustomAttributes (fi));
 201                                         if (dc != null)
 202                                                 return new ConstSpec (declaringType, definition, field_type, fi, mod, dc);
 203                                 }
 204
 205                                 mod |= Modifiers.READONLY;
 206                         } else {
 207                                 var req_mod = fi.GetRequiredCustomModifiers ();
 208                                 if (req_mod.Length > 0 && HasVolatileModifier (req_mod))
 209                                         mod |= Modifiers.VOLATILE;
 210                         }
 211
 212                         if ((fa & FieldAttributes.Static) != 0) {
 213                                 mod |= Modifiers.STATIC;
 214                         } else {
 215                                 // Fixed buffers cannot be static
 216                                 if (declaringType.IsStruct && field_type.IsStruct && field_type.IsNested &&
 217                                         HasAttribute (CustomAttributeData.GetCustomAttributes (fi), "FixedBufferAttribute", CompilerServicesNamespace)) {
 218
 219                                         // TODO: Sanity check on field_type (only few types are allowed)
 220                                         var element_field = CreateField (fi.FieldType.GetField (FixedField.FixedElementName), declaringType);
 221                                         return new FixedFieldSpec (declaringType, definition, fi, element_field, mod);
 222                                 }
 223                         }
 224
 225                         return new FieldSpec (declaringType, definition, field_type, fi, mod);
 226                 }
 227
 228                 public EventSpec CreateEvent (EventInfo ei, TypeSpec declaringType, MethodSpec add, MethodSpec remove)
 229                 {
 230                         add.IsAccessor = true;
 231                         remove.IsAccessor = true;
 232
 233                         if (add.Modifiers != remove.Modifiers)
 234                                 throw new NotImplementedException ("Different accessor modifiers " + ei.Name);
 235
 236                         var event_type = ImportType (ei.EventHandlerType, new DynamicTypeReader (ei));
 237                         var definition = new ImportedMemberDefinition (ei, event_type,  this);
 238                         return new EventSpec (declaringType, definition, event_type, add.Modifiers, add, remove);
 239                 }
 240
 241                 TypeParameterSpec[] CreateGenericParameters (MetaType type, TypeSpec declaringType)
 242                 {
 243                         var tparams = type.GetGenericArguments ();
 244
 245                         int parent_owned_count;
 246                         if (type.IsNested) {
 247                                 parent_owned_count = type.DeclaringType.GetGenericArguments ().Length;
 248
 249                                 //
 250                                 // System.Reflection duplicates parent type parameters for each
 251                                 // nested type with slightly modified properties (eg. different owner)
 252                                 // This just makes things more complicated (think of cloned constraints)
 253                                 // therefore we remap any nested type owned by parent using `type_cache'
 254                                 // to the single TypeParameterSpec
 255                                 //
 256                                 if (declaringType != null && parent_owned_count > 0) {
 257                                         int read_count = 0;
 258                                         while (read_count != parent_owned_count) {
 259                                                 var tparams_count = declaringType.Arity;
 260                                                 if (tparams_count != 0) {
 261                                                         var parent_tp = declaringType.MemberDefinition.TypeParameters;
 262                                                         read_count += tparams_count;
 263                                                         for (int i = 0; i < tparams_count; i++) {
 264                                                                 import_cache.Add (tparams[parent_owned_count - read_count + i], parent_tp[i]);
 265                                                         }
 266                                                 }
 267
 268                                                 declaringType = declaringType.DeclaringType;
 269                                         }
 270                                 }
 271                         } else {
 272                                 parent_owned_count = 0;
 273                         }
 274
 275                         if (tparams.Length - parent_owned_count == 0)
 276                                 return null;
 277
 278                         return CreateGenericParameters (parent_owned_count, tparams);
 279                 }
 280
 281                 TypeParameterSpec[] CreateGenericParameters (int first, MetaType[] tparams)
 282                 {
 283                         var tspec = new TypeParameterSpec[tparams.Length - first];
 284                         for (int pos = first; pos < tparams.Length; ++pos) {
 285                                 var type = tparams[pos];
 286                                 int index = pos - first;
 287
 288                                 tspec[index] = (TypeParameterSpec) CreateType (type, new DynamicTypeReader (), false);
 289                         }
 290
 291                         return tspec;
 292                 }
 293
 294                 TypeSpec[] CreateGenericArguments (int first, MetaType[] tparams, DynamicTypeReader dtype)
 295                 {
 296                         ++dtype.Position;
 297
 298                         var tspec = new TypeSpec [tparams.Length - first];
 299                         for (int pos = first; pos < tparams.Length; ++pos) {
 300                                 var type = tparams[pos];
 301                                 int index = pos - first;
 302
 303                                 TypeSpec spec;
 304                                 if (type.HasElementType) {
 305                                         var element = type.GetElementType ();
 306                                         ++dtype.Position;
 307                                         spec = ImportType (element, dtype);
 308
 309                                         if (!type.IsArray) {
 310                                                 throw new NotImplementedException ("Unknown element type " + type.ToString ());
 311                                         }
 312
 313                                         spec = ArrayContainer.MakeType (module, spec, type.GetArrayRank ());
 314                                 } else {
 315                                         spec = CreateType (type, dtype, true);
 316
 317                                         //
 318                                         // We treat nested generic types as inflated internally where
 319                                         // reflection uses type definition
 320                                         //
 321                                         // class A<T> {
 322                                         //    IFoo<A<T>> foo;   // A<T> is definition in this case
 323                                         // }
 324                                         //
 325                                         // TODO: Is full logic from CreateType needed here as well?
 326                                         //
 327                                         if (!IsMissingType (type) && type.IsGenericTypeDefinition) {
 328                                                 var targs = CreateGenericArguments (0, type.GetGenericArguments (), dtype);
 329                                                 spec = spec.MakeGenericType (module, targs);
 330                                         }
 331                                 }
 332
 333                                 ++dtype.Position;
 334                                 tspec[index] = spec;
 335                         }
 336
 337                         return tspec;
 338                 }
 339
 340                 public MethodSpec CreateMethod (MethodBase mb, TypeSpec declaringType)
 341                 {
 342                         Modifiers mod = ReadMethodModifiers (mb, declaringType);
 343                         TypeParameterSpec[] tparams;
 344
 345                         var parameters = CreateParameters (declaringType, mb.GetParameters (), mb);
 346
 347                         if (mb.IsGenericMethod) {
 348                                 if (!mb.IsGenericMethodDefinition)
 349                                         throw new NotSupportedException ("assert");
 350
 351                                 tparams = CreateGenericParameters (0, mb.GetGenericArguments ());
 352                         } else {
 353                                 tparams = null;
 354                         }
 355
 356                         MemberKind kind;
 357                         TypeSpec returnType;
 358                         if (mb.MemberType == MemberTypes.Constructor) {
 359                                 kind = MemberKind.Constructor;
 360                                 returnType = module.Compiler.BuiltinTypes.Void;
 361                         } else {
 362                                 //
 363                                 // Detect operators and destructors
 364                                 //
 365                                 string name = mb.Name;
 366                                 kind = MemberKind.Method;
 367                                 if (tparams == null && !mb.DeclaringType.IsInterface && name.Length > 6) {
 368                                         if ((mod & (Modifiers.STATIC | Modifiers.PUBLIC)) == (Modifiers.STATIC | Modifiers.PUBLIC)) {
 369                                                 if (name[2] == '_' && name[1] == 'p' && name[0] == 'o') {
 370                                                         var op_type = Operator.GetType (name);
 371                                                         if (op_type.HasValue && parameters.Count > 0 && parameters.Count < 3) {
 372                                                                 kind = MemberKind.Operator;
 373                                                         }
 374                                                 }
 375                                         } else if (parameters.IsEmpty && name == Destructor.MetadataName) {
 376                                                 kind = MemberKind.Destructor;
 377                                                 if (declaringType.BuiltinType == BuiltinTypeSpec.Type.Object) {
 378                                                         mod &= ~Modifiers.OVERRIDE;
 379                                                         mod |= Modifiers.VIRTUAL;
 380                                                 }
 381                                         }
 382                                 }
 383
 384                                 var mi = (MethodInfo) mb;
 385                                 returnType = ImportType (mi.ReturnType, new DynamicTypeReader (mi.ReturnParameter));
 386
 387                                 // Cannot set to OVERRIDE without full hierarchy checks
 388                                 // this flag indicates that the method could be override
 389                                 // but further validation is needed
 390                                 if ((mod & Modifiers.OVERRIDE) != 0) {
 391                                         bool is_real_override = false;
 392                                         if (kind == MemberKind.Method && declaringType.BaseType != null) {
 393                                                 var filter = MemberFilter.Method (name, tparams != null ? tparams.Length : 0, parameters, null);
 394                                                 var candidate = MemberCache.FindMember (declaringType.BaseType, filter, BindingRestriction.None);
 395
 396                                                 //
 397                                                 // For imported class method do additional validation to be sure that metadata
 398                                                 // override flag was correct
 399                                                 //
 400                                                 // Difference between protected internal and protected is ok
 401                                                 //
 402                                                 const Modifiers conflict_mask = Modifiers.AccessibilityMask & ~Modifiers.INTERNAL;
 403                                                 if (candidate != null && (candidate.Modifiers & conflict_mask) == (mod & conflict_mask) && !candidate.IsStatic) {
 404                                                         is_real_override = true;
 405                                                 }
 406                                         }
 407
 408                                         if (!is_real_override) {
 409                                                 mod &= ~Modifiers.OVERRIDE;
 410                                                 if ((mod & Modifiers.SEALED) != 0)
 411                                                         mod &= ~Modifiers.SEALED;
 412                                                 else
 413                                                         mod |= Modifiers.VIRTUAL;
 414                                         }
 415                                 }
 416                         }
 417
 418                         IMemberDefinition definition;
 419                         if (tparams != null) {
 420                                 var gmd = new ImportedGenericMethodDefinition ((MethodInfo) mb, returnType, parameters, tparams, this);
 421                                 foreach (var tp in gmd.TypeParameters) {
 422                                         ImportTypeParameterTypeConstraints (tp, tp.GetMetaInfo ());
 423                                 }
 424
 425                                 definition = gmd;
 426                         } else {
 427                                 definition = new ImportedParameterMemberDefinition (mb, returnType, parameters, this);
 428                         }
 429
 430                         MethodSpec ms = new MethodSpec (kind, declaringType, definition, returnType, mb, parameters, mod);
 431                         if (tparams != null)
 432                                 ms.IsGeneric = true;
 433
 434                         return ms;
 435                 }
 436
 437                 //
 438                 // Imports System.Reflection parameters
 439                 //
 440                 AParametersCollection CreateParameters (TypeSpec parent, ParameterInfo[] pi, MethodBase method)
 441                 {
 442                         int varargs = method != null && (method.CallingConvention & CallingConventions.VarArgs) != 0 ? 1 : 0;
 443
 444                         if (pi.Length == 0 && varargs == 0)
 445                                 return ParametersCompiled.EmptyReadOnlyParameters;
 446
 447                         TypeSpec[] types = new TypeSpec[pi.Length + varargs];
 448                         IParameterData[] par = new IParameterData[pi.Length + varargs];
 449                         bool is_params = false;
 450                         for (int i = 0; i < pi.Length; i++) {
 451                                 ParameterInfo p = pi[i];
 452                                 Parameter.Modifier mod = 0;
 453                                 Expression default_value = null;
 454                                 if (p.ParameterType.IsByRef) {
 455                                         if ((p.Attributes & (ParameterAttributes.Out | ParameterAttributes.In)) == ParameterAttributes.Out)
 456                                                 mod = Parameter.Modifier.OUT;
 457                                         else
 458                                                 mod = Parameter.Modifier.REF;
 459
 460                                         //
 461                                         // Strip reference wrapping
 462                                         //
 463                                         var el = p.ParameterType.GetElementType ();
 464                                         types[i] = ImportType (el, new DynamicTypeReader (p));  // TODO: 1-based positio to be csc compatible
 465                                 } else if (i == 0 && method.IsStatic && parent.IsStatic && parent.MemberDefinition.DeclaringAssembly.HasExtensionMethod &&
 466                                         HasAttribute (CustomAttributeData.GetCustomAttributes (method), "ExtensionAttribute", CompilerServicesNamespace)) {
 467                                         mod = Parameter.Modifier.This;
 468                                         types[i] = ImportType (p.ParameterType);
 469                                 } else {
 470                                         types[i] = ImportType (p.ParameterType, new DynamicTypeReader (p));
 471
 472                                         if (i >= pi.Length - 2 && types[i] is ArrayContainer) {
 473                                                 if (HasAttribute (CustomAttributeData.GetCustomAttributes (p), "ParamArrayAttribute", "System")) {
 474                                                         mod = Parameter.Modifier.PARAMS;
 475                                                         is_params = true;
 476                                                 }
 477                                         }
 478
 479                                         if (!is_params && p.IsOptional) {
 480                                                 object value = p.RawDefaultValue;
 481                                                 var ptype = types[i];
 482                                                 if ((p.Attributes & ParameterAttributes.HasDefault) != 0 && ptype.Kind != MemberKind.TypeParameter && (value != null || TypeSpec.IsReferenceType (ptype))) {
 483                                                         if (value == null) {
 484                                                                 default_value = Constant.CreateConstant (ptype, null, Location.Null);
 485                                                         } else {
 486                                                                 default_value = ImportParameterConstant (value);
 487
 488                                                                 if (ptype.IsEnum) {
 489                                                                         default_value = new EnumConstant ((Constant) default_value, ptype);
 490                                                                 }
 491                                                         }
 492                                                 } else if (value == Missing.Value) {
 493                                                         default_value = EmptyExpression.MissingValue;
 494                                                 } else if (value == null) {
 495                                                         default_value = new DefaultValueExpression (new TypeExpression (ptype, Location.Null), Location.Null);
 496                                                 } else if (ptype.BuiltinType == BuiltinTypeSpec.Type.Decimal) {
 497                                                         default_value = ImportParameterConstant (value);
 498                                                 }
 499                                         }
 500                                 }
 501
 502                                 par[i] = new ParameterData (p.Name, mod, default_value);
 503                         }
 504
 505                         if (varargs != 0) {
 506                                 par[par.Length - 1] = new ArglistParameter (Location.Null);
 507                                 types[types.Length - 1] = InternalType.Arglist;
 508                         }
 509
 510                         return method != null ?
 511                                 new ParametersImported (par, types, varargs != 0, is_params) :
 512                                 new ParametersImported (par, types, is_params);
 513                 }
 514
 515                 //
 516                 // Returns null when the property is not valid C# property
 517                 //
 518                 public PropertySpec CreateProperty (PropertyInfo pi, TypeSpec declaringType, MethodSpec get, MethodSpec set)
 519                 {
 520                         Modifiers mod = 0;
 521                         AParametersCollection param = null;
 522                         TypeSpec type = null;
 523                         if (get != null) {
 524                                 mod = get.Modifiers;
 525                                 param = get.Parameters;
 526                                 type = get.ReturnType;
 527                         }
 528
 529                         bool is_valid_property = true;
 530                         if (set != null) {
 531                                 if (set.ReturnType.Kind != MemberKind.Void)
 532                                         is_valid_property = false;
 533
 534                                 var set_param_count = set.Parameters.Count - 1;
 535
 536                                 if (set_param_count < 0) {
 537                                         set_param_count = 0;
 538                                         is_valid_property = false;
 539                                 }
 540
 541                                 var set_type = set.Parameters.Types[set_param_count];
 542
 543                                 if (mod == 0) {
 544                                         AParametersCollection set_based_param;
 545
 546                                         if (set_param_count == 0) {
 547                                                 set_based_param = ParametersCompiled.EmptyReadOnlyParameters;
 548                                         } else {
 549                                                 //
 550                                                 // Create indexer parameters based on setter method parameters (the last parameter has to be removed)
 551                                                 //
 552                                                 var data = new IParameterData[set_param_count];
 553                                                 var types = new TypeSpec[set_param_count];
 554                                                 Array.Copy (set.Parameters.FixedParameters, data, set_param_count);
 555                                                 Array.Copy (set.Parameters.Types, types, set_param_count);
 556                                                 set_based_param = new ParametersImported (data, types, set.Parameters.HasParams);
 557                                         }
 558
 559                                         mod = set.Modifiers;
 560                                         param = set_based_param;
 561                                         type = set_type;
 562                                 } else {
 563                                         if (set_param_count != get.Parameters.Count)
 564                                                 is_valid_property = false;
 565
 566                                         if (get.ReturnType != set_type)
 567                                                 is_valid_property = false;
 568
 569                                         // Possible custom accessor modifiers
 570                                         if ((mod & Modifiers.AccessibilityMask) != (set.Modifiers & Modifiers.AccessibilityMask)) {
 571                                                 var get_acc = mod & Modifiers.AccessibilityMask;
 572                                                 if (get_acc != Modifiers.PUBLIC) {
 573                                                         var set_acc = set.Modifiers & Modifiers.AccessibilityMask;
 574                                                         // If the accessor modifiers are not same, do extra restriction checks
 575                                                         if (get_acc != set_acc) {
 576                                                                 var get_restr = ModifiersExtensions.IsRestrictedModifier (get_acc, set_acc);
 577                                                                 var set_restr = ModifiersExtensions.IsRestrictedModifier (set_acc, get_acc);
 578                                                                 if (get_restr && set_restr) {
 579                                                                         is_valid_property = false; // Neither is more restrictive
 580                                                                 }
 581
 582                                                                 if (get_restr) {
 583                                                                         mod &= ~Modifiers.AccessibilityMask;
 584                                                                         mod |= set_acc;
 585                                                                 }
 586                                                         }
 587                                                 }
 588                                         }
 589                                 }
 590                         }
 591
 592                         PropertySpec spec = null;
 593                         if (!param.IsEmpty) {
 594                                 var index_name = declaringType.MemberDefinition.GetAttributeDefaultMember ();
 595                                 if (index_name == null) {
 596                                         is_valid_property = false;
 597                                 } else {
 598                                         if (get != null) {
 599                                                 if (get.IsStatic)
 600                                                         is_valid_property = false;
 601                                                 if (get.Name.IndexOf (index_name, StringComparison.Ordinal) != 4)
 602                                                         is_valid_property = false;
 603                                         }
 604                                         if (set != null) {
 605                                                 if (set.IsStatic)
 606                                                         is_valid_property = false;
 607                                                 if (set.Name.IndexOf (index_name, StringComparison.Ordinal) != 4)
 608                                                         is_valid_property = false;
 609                                         }
 610                                 }
 611
 612                                 if (is_valid_property)
 613                                         spec = new IndexerSpec (declaringType, new ImportedParameterMemberDefinition (pi, type, param, this), type, param, pi, mod);
 614                         }
 615
 616                         if (spec == null)
 617                                 spec = new PropertySpec (MemberKind.Property, declaringType, new ImportedMemberDefinition (pi, type, this), type, pi, mod);
 618
 619                         if (!is_valid_property) {
 620                                 spec.IsNotRealProperty = true;
 621                                 return spec;
 622                         }
 623
 624                         if (set != null)
 625                                 spec.Set = set;
 626                         if (get != null)
 627                                 spec.Get = get;
 628
 629                         return spec;
 630                 }
 631
 632                 public TypeSpec CreateType (MetaType type)
 633                 {
 634                         return CreateType (type, new DynamicTypeReader (), true);
 635                 }
 636
 637                 public TypeSpec CreateNestedType (MetaType type, TypeSpec declaringType)
 638                 {
 639                         return CreateType (type, declaringType, new DynamicTypeReader (type), false);
 640                 }
 641
 642                 TypeSpec CreateType (MetaType type, DynamicTypeReader dtype, bool canImportBaseType)
 643                 {
 644                         TypeSpec declaring_type;
 645                         if (type.IsNested && !type.IsGenericParameter)
 646                                 declaring_type = CreateType (type.DeclaringType, new DynamicTypeReader (type.DeclaringType), true);
 647                         else
 648                                 declaring_type = null;
 649
 650                         return CreateType (type, declaring_type, dtype, canImportBaseType);
 651                 }
 652
 653                 TypeSpec CreateType (MetaType type, TypeSpec declaringType, DynamicTypeReader dtype, bool canImportBaseType)
 654                 {
 655                         TypeSpec spec;
 656                         if (import_cache.TryGetValue (type, out spec)) {
 657                                 if (spec.BuiltinType == BuiltinTypeSpec.Type.Object) {
 658                                         if (dtype.IsDynamicObject (this))
 659                                                 return module.Compiler.BuiltinTypes.Dynamic;
 660
 661                                         return spec;
 662                                 }
 663
 664                                 if (!spec.IsGeneric || type.IsGenericTypeDefinition)
 665                                         return spec;
 666
 667                                 if (!dtype.HasDynamicAttribute (this))
 668                                         return spec;
 669
 670                                 // We've found same object in the cache but this one has a dynamic custom attribute
 671                                 // and it's most likely dynamic version of same type IFoo<object> agains IFoo<dynamic>
 672                                 // Do type resolve process again in that case
 673
 674                                 // TODO: Handle cases where they still unify
 675                         }
 676
 677                         if (IsMissingType (type)) {
 678                                 spec = new TypeSpec (MemberKind.MissingType, declaringType, new ImportedTypeDefinition (type, this), type, Modifiers.PUBLIC);
 679                                 spec.MemberCache = MemberCache.Empty;
 680                                 import_cache.Add (type, spec);
 681                                 return spec;
 682                         }
 683
 684                         if (type.IsGenericType && !type.IsGenericTypeDefinition) {
 685                                 var type_def = type.GetGenericTypeDefinition ();
 686
 687                                 // Generic type definition can also be forwarded
 688                                 if (compiled_types.TryGetValue (type_def, out spec))
 689                                         return spec;
 690
 691                                 var targs = CreateGenericArguments (0, type.GetGenericArguments (), dtype);
 692                                 if (declaringType == null) {
 693                                         // Simple case, no nesting
 694                                         spec = CreateType (type_def, null, new DynamicTypeReader (), canImportBaseType);
 695                                         spec = spec.MakeGenericType (module, targs);
 696                                 } else {
 697                                         //
 698                                         // Nested type case, converting .NET types like
 699                                         // A`1.B`1.C`1<int, long, string> to typespec like
 700                                         // A<int>.B<long>.C<string>
 701                                         //
 702                                         var nested_hierarchy = new List<TypeSpec> ();
 703                                         while (declaringType.IsNested) {
 704                                                 nested_hierarchy.Add (declaringType);
 705                                                 declaringType = declaringType.DeclaringType;
 706                                         }
 707
 708                                         int targs_pos = 0;
 709                                         if (declaringType.Arity > 0) {
 710                                                 spec = declaringType.MakeGenericType (module, targs.Skip (targs_pos).Take (declaringType.Arity).ToArray ());
 711                                                 targs_pos = spec.Arity;
 712                                         } else {
 713                                                 spec = declaringType;
 714                                         }
 715
 716                                         for (int i = nested_hierarchy.Count; i != 0; --i) {
 717                                                 var t = nested_hierarchy [i - 1];
 718                                                 spec = MemberCache.FindNestedType (spec, t.Name, t.Arity);
 719                                                 if (t.Arity > 0) {
 720                                                         spec = spec.MakeGenericType (module, targs.Skip (targs_pos).Take (spec.Arity).ToArray ());
 721                                                         targs_pos += t.Arity;
 722                                                 }
 723                                         }
 724
 725                                         string name = type.Name;
 726                                         int index = name.IndexOf ('`');
 727                                         if (index > 0)
 728                                                 name = name.Substring (0, index);
 729
 730                                         spec = MemberCache.FindNestedType (spec, name, targs.Length - targs_pos);
 731                                         if (spec == null)
 732                                                 return null;
 733
 734                                         if (spec.Arity > 0) {
 735                                                 spec = spec.MakeGenericType (module, targs.Skip (targs_pos).ToArray ());
 736                                         }
 737                                 }
 738
 739                                 // Don't add generic type with dynamic arguments, they can interfere with same type
 740                                 // using object type arguments
 741                                 if (!spec.HasDynamicElement) {
 742
 743                                         // Add to reading cache to speed up reading
 744                                         if (!import_cache.ContainsKey (type))
 745                                                 import_cache.Add (type, spec);
 746                                 }
 747
 748                                 return spec;
 749                         }
 750
 751                         Modifiers mod;
 752                         MemberKind kind;
 753
 754                         var ma = type.Attributes;
 755                         switch (ma & TypeAttributes.VisibilityMask) {
 756                         case TypeAttributes.Public:
 757                         case TypeAttributes.NestedPublic:
 758                                 mod = Modifiers.PUBLIC;
 759                                 break;
 760                         case TypeAttributes.NestedPrivate:
 761                                 mod = Modifiers.PRIVATE;
 762                                 break;
 763                         case TypeAttributes.NestedFamily:
 764                                 mod = Modifiers.PROTECTED;
 765                                 break;
 766                         case TypeAttributes.NestedFamORAssem:
 767                                 mod = Modifiers.PROTECTED | Modifiers.INTERNAL;
 768                                 break;
 769                         default:
 770                                 mod = Modifiers.INTERNAL;
 771                                 break;
 772                         }
 773
 774                         if ((ma & TypeAttributes.Interface) != 0) {
 775                                 kind = MemberKind.Interface;
 776                         } else if (type.IsGenericParameter) {
 777                                 kind = MemberKind.TypeParameter;
 778                         } else {
 779                                 var base_type = type.BaseType;
 780                                 if (base_type == null || (ma & TypeAttributes.Abstract) != 0) {
 781                                         kind = MemberKind.Class;
 782                                 } else {
 783                                         kind = DetermineKindFromBaseType (base_type);
 784                                         if (kind == MemberKind.Struct || kind == MemberKind.Delegate) {
 785                                                 mod |= Modifiers.SEALED;
 786                                         }
 787                                 }
 788
 789                                 if (kind == MemberKind.Class) {
 790                                         if ((ma & TypeAttributes.Sealed) != 0) {
 791                                                 mod |= Modifiers.SEALED;
 792                                                 if ((ma & TypeAttributes.Abstract) != 0)
 793                                                         mod |= Modifiers.STATIC;
 794                                         } else if ((ma & TypeAttributes.Abstract) != 0) {
 795                                                 mod |= Modifiers.ABSTRACT;
 796                                         }
 797                                 }
 798                         }
 799
 800                         var definition = new ImportedTypeDefinition (type, this);
 801                         TypeSpec pt;
 802
 803                         if (kind == MemberKind.Enum) {
 804                                 const BindingFlags underlying_member = BindingFlags.DeclaredOnly |
 805                                         BindingFlags.Instance |
 806                                         BindingFlags.Public | BindingFlags.NonPublic;
 807
 808                                 var type_members = type.GetFields (underlying_member);
 809                                 foreach (var type_member in type_members) {
 810                                         spec = new EnumSpec (declaringType, definition, CreateType (type_member.FieldType), type, mod);
 811                                         break;
 812                                 }
 813
 814                                 if (spec == null)
 815                                         kind = MemberKind.Class;
 816
 817                         } else if (kind == MemberKind.TypeParameter) {
 818                                 spec = CreateTypeParameter (type, declaringType);
 819                         } else if (type.IsGenericTypeDefinition) {
 820                                 definition.TypeParameters = CreateGenericParameters (type, declaringType);
 821                         } else if (compiled_types.TryGetValue (type, out pt)) {
 822                                 //
 823                                 // Same type was found in inside compiled types. It's
 824                                 // either build-in type or forward referenced typed
 825                                 // which point into just compiled assembly.
 826                                 //
 827                                 spec = pt;
 828                                 BuiltinTypeSpec bts = pt as BuiltinTypeSpec;
 829                                 if (bts != null)
 830                                         bts.SetDefinition (definition, type, mod);
 831                         }
 832
 833                         if (spec == null)
 834                                 spec = new TypeSpec (kind, declaringType, definition, type, mod);
 835
 836                         import_cache.Add (type, spec);
 837
 838                         //
 839                         // Two stage setup as the base type can be inflated declaring type or
 840                         // another nested type inside same declaring type which has not been
 841                         // loaded, therefore we can import a base type of nested types once
 842                         // the types have been imported
 843                         //
 844                         if (canImportBaseType)
 845                                 ImportTypeBase (spec, type);
 846
 847                         return spec;
 848                 }
 849
 850                 public IAssemblyDefinition GetAssemblyDefinition (Assembly assembly)
 851                 {
 852                         IAssemblyDefinition found;
 853                         if (!assembly_2_definition.TryGetValue (assembly, out found)) {
 854
 855                                 // This can happen in dynamic context only
 856                                 var def = new ImportedAssemblyDefinition (assembly, this);
 857                                 assembly_2_definition.Add (assembly, def);
 858                                 def.ReadAttributes ();
 859                                 found = def;
 860                         }
 861
 862                         return found;
 863                 }
 864
 865                 public void ImportTypeBase (MetaType type)
 866                 {
 867                         TypeSpec spec = import_cache[type];
 868                         if (spec != null)
 869                                 ImportTypeBase (spec, type);
 870                 }
 871
 872                 TypeParameterSpec CreateTypeParameter (MetaType type, TypeSpec declaringType)
 873                 {
 874                         Variance variance;
 875                         switch (type.GenericParameterAttributes & GenericParameterAttributes.VarianceMask) {
 876                         case GenericParameterAttributes.Covariant:
 877                                 variance = Variance.Covariant;
 878                                 break;
 879                         case GenericParameterAttributes.Contravariant:
 880                                 variance = Variance.Contravariant;
 881                                 break;
 882                         default:
 883                                 variance = Variance.None;
 884                                 break;
 885                         }
 886
 887                         SpecialConstraint special = SpecialConstraint.None;
 888                         var import_special = type.GenericParameterAttributes & GenericParameterAttributes.SpecialConstraintMask;
 889
 890                         if ((import_special & GenericParameterAttributes.NotNullableValueTypeConstraint) != 0) {
 891                                 special |= SpecialConstraint.Struct;
 892                         } else if ((import_special & GenericParameterAttributes.DefaultConstructorConstraint) != 0) {
 893                                 special = SpecialConstraint.Constructor;
 894                         }
 895
 896                         if ((import_special & GenericParameterAttributes.ReferenceTypeConstraint) != 0) {
 897                                 special |= SpecialConstraint.Class;
 898                         }
 899
 900                         TypeParameterSpec spec;
 901                         var def = new ImportedTypeParameterDefinition (type, this);
 902                         if (type.DeclaringMethod != null) {
 903                                 spec = new TypeParameterSpec (type.GenericParameterPosition, def, special, variance, type);
 904                         } else {
 905                                 spec = new TypeParameterSpec (declaringType, type.GenericParameterPosition, def, special, variance, type);
 906                         }
 907
 908                         return spec;
 909                 }
 910
 911                 //
 912                 // Test for a custom attribute type match. Custom attributes are not really predefined globaly
 913                 // they can be assembly specific therefore we do check based on names only
 914                 //
 915                 public bool HasAttribute (IList<CustomAttributeData> attributesData, string attrName, string attrNamespace)
 916                 {
 917                         if (attributesData.Count == 0)
 918                                 return false;
 919
 920                         string ns, name;
 921                         foreach (var attr in attributesData) {
 922                                 GetCustomAttributeTypeName (attr, out ns, out name);
 923                                 if (name == attrName && ns == attrNamespace)
 924                                         return true;
 925                         }
 926
 927                         return false;
 928                 }
 929
 930                 void ImportTypeBase (TypeSpec spec, MetaType type)
 931                 {
 932                         if (spec.Kind == MemberKind.Interface)
 933                                 spec.BaseType = module.Compiler.BuiltinTypes.Object;
 934                         else if (type.BaseType != null) {
 935                                 TypeSpec base_type;
 936                                 if (!IsMissingType (type.BaseType) && type.BaseType.IsGenericType)
 937                                         base_type = CreateType (type.BaseType, new DynamicTypeReader (type), true);
 938                                 else
 939                                         base_type = CreateType (type.BaseType);
 940
 941                                 spec.BaseType = base_type;
 942                         }
 943
 944                         MetaType[] ifaces;
 945 #if STATIC
 946                         ifaces = type.__GetDeclaredInterfaces ();
 947                         if (ifaces.Length != 0) {
 948                                 foreach (var iface in ifaces) {
 949                                         var it = CreateType (iface);
 950                                         if (it == null)
 951                                                 continue;
 952
 953                                         spec.AddInterface (it);
 954
 955                                         // Unfortunately not all languages expand inherited interfaces
 956                                         var bifaces = it.Interfaces;
 957                                         if (bifaces != null) {
 958                                                 foreach (var biface in bifaces) {
 959                                                         spec.AddInterface (biface);
 960                                                 }
 961                                         }
 962                                 }
 963                         }
 964
 965                         if (spec.BaseType != null) {
 966                                 var bifaces = spec.BaseType.Interfaces;
 967                                 if (bifaces != null) {
 968                                         foreach (var iface in bifaces)
 969                                                 spec.AddInterface (iface);
 970                                 }
 971                         }
 972 #else
 973                         ifaces = type.GetInterfaces ();
 974
 975                         if (ifaces.Length > 0) {
 976                                 foreach (var iface in ifaces) {
 977                                         spec.AddInterface (CreateType (iface));
 978                                 }
 979                         }
 980 #endif
 981
 982                         if (spec.MemberDefinition.TypeParametersCount > 0) {
 983                                 foreach (var tp in spec.MemberDefinition.TypeParameters) {
 984                                         ImportTypeParameterTypeConstraints (tp, tp.GetMetaInfo ());
 985                                 }
 986                         }
 987
 988                 }
 989
 990                 protected void ImportTypes (MetaType[] types, Namespace targetNamespace, bool hasExtensionTypes)
 991                 {
 992                         Namespace ns = targetNamespace;
 993                         string prev_namespace = null;
 994                         foreach (var t in types) {
 995                                 if (t == null)
 996                                         continue;
 997
 998                                 // Be careful not to trigger full parent type loading
 999                                 if (t.MemberType == MemberTypes.NestedType)
1000                                         continue;
1001
1002                                 if (t.Name[0] == '<')
1003                                         continue;
1004
1005                                 var it = CreateType (t, null, new DynamicTypeReader (t), true);
1006                                 if (it == null)
1007                                         continue;
1008
1009                                 if (prev_namespace != t.Namespace) {
1010                                         ns = t.Namespace == null ? targetNamespace : targetNamespace.GetNamespace (t.Namespace, true);
1011                                         prev_namespace = t.Namespace;
1012                                 }
1013
1014                                 ns.AddType (module, it);
1015
1016                                 if (it.IsStatic && hasExtensionTypes &&
1017                                         HasAttribute (CustomAttributeData.GetCustomAttributes (t), "ExtensionAttribute", CompilerServicesNamespace)) {
1018                                         it.SetExtensionMethodContainer ();
1019                                 }
1020                         }
1021                 }
1022
1023                 void ImportTypeParameterTypeConstraints (TypeParameterSpec spec, MetaType type)
1024                 {
1025                         var constraints = type.GetGenericParameterConstraints ();
1026                         List<TypeSpec> tparams = null;
1027                         foreach (var ct in constraints) {
1028                                 if (ct.IsGenericParameter) {
1029                                         if (tparams == null)
1030                                                 tparams = new List<TypeSpec> ();
1031
1032                                         tparams.Add (CreateType (ct));
1033                                         continue;
1034                                 }
1035
1036                                 if (!IsMissingType (ct) && ct.IsClass) {
1037                                         spec.BaseType = CreateType (ct);
1038                                         continue;
1039                                 }
1040
1041                                 spec.AddInterface (CreateType (ct));
1042                         }
1043
1044                         if (spec.BaseType == null)
1045                                 spec.BaseType = module.Compiler.BuiltinTypes.Object;
1046
1047                         if (tparams != null)
1048                                 spec.TypeArguments = tparams.ToArray ();
1049                 }
1050
1051                 Constant ImportParameterConstant (object value)
1052                 {
1053                         //
1054                         // Get type of underlying value as int constant can be used for object
1055                         // parameter type. This is not allowed in C# but other languages can do that
1056                         //
1057                         var types = module.Compiler.BuiltinTypes;
1058                         switch (System.Type.GetTypeCode (value.GetType ())) {
1059                         case TypeCode.Boolean:
1060                                 return new BoolConstant (types, (bool) value, Location.Null);
1061                         case TypeCode.Byte:
1062                                 return new ByteConstant (types, (byte) value, Location.Null);
1063                         case TypeCode.Char:
1064                                 return new CharConstant (types, (char) value, Location.Null);
1065                         case TypeCode.Decimal:
1066                                 return new DecimalConstant (types, (decimal) value, Location.Null);
1067                         case TypeCode.Double:
1068                                 return new DoubleConstant (types, (double) value, Location.Null);
1069                         case TypeCode.Int16:
1070                                 return new ShortConstant (types, (short) value, Location.Null);
1071                         case TypeCode.Int32:
1072                                 return new IntConstant (types, (int) value, Location.Null);
1073                         case TypeCode.Int64:
1074                                 return new LongConstant (types, (long) value, Location.Null);
1075                         case TypeCode.SByte:
1076                                 return new SByteConstant (types, (sbyte) value, Location.Null);
1077                         case TypeCode.Single:
1078                                 return new FloatConstant (types, (float) value, Location.Null);
1079                         case TypeCode.String:
1080                                 return new StringConstant (types, (string) value, Location.Null);
1081                         case TypeCode.UInt16:
1082                                 return new UShortConstant (types, (ushort) value, Location.Null);
1083                         case TypeCode.UInt32:
1084                                 return new UIntConstant (types, (uint) value, Location.Null);
1085                         case TypeCode.UInt64:
1086                                 return new ULongConstant (types, (ulong) value, Location.Null);
1087                         }
1088
1089                         throw new NotImplementedException (value.GetType ().ToString ());
1090                 }
1091
1092                 public TypeSpec ImportType (MetaType type)
1093                 {
1094                         return ImportType (type, new DynamicTypeReader (type));
1095                 }
1096
1097                 TypeSpec ImportType (MetaType type, DynamicTypeReader dtype)
1098                 {
1099                         if (type.HasElementType) {
1100                                 var element = type.GetElementType ();
1101                                 ++dtype.Position;
1102                                 var spec = ImportType (element, dtype);
1103
1104                                 if (type.IsArray)
1105                                         return ArrayContainer.MakeType (module, spec, type.GetArrayRank ());
1106                                 if (type.IsByRef)
1107                                         return ReferenceContainer.MakeType (module, spec);
1108                                 if (type.IsPointer)
1109                                         return PointerContainer.MakeType (module, spec);
1110
1111                                 throw new NotImplementedException ("Unknown element type " + type.ToString ());
1112                         }
1113
1114                         return CreateType (type, dtype, true);
1115                 }
1116
1117                 static bool IsMissingType (MetaType type)
1118                 {
1119 #if STATIC
1120                         return type.__IsMissing;
1121 #else
1122                         return false;
1123 #endif
1124                 }
1125
1126                 //
1127                 // Decimal constants cannot be encoded in the constant blob, and thus are marked
1128                 // as IsInitOnly ('readonly' in C# parlance).  We get its value from the
1129                 // DecimalConstantAttribute metadata.
1130                 //
1131                 Constant ReadDecimalConstant (IList<CustomAttributeData> attrs)
1132                 {
1133                         if (attrs.Count == 0)
1134                                 return null;
1135
1136                         string name, ns;
1137                         foreach (var ca in attrs) {
1138                                 GetCustomAttributeTypeName (ca, out ns, out name);
1139                                 if (name != "DecimalConstantAttribute" || ns != CompilerServicesNamespace)
1140                                         continue;
1141
1142                                 var value = new decimal (
1143                                         (int) (uint) ca.ConstructorArguments[4].Value,
1144                                         (int) (uint) ca.ConstructorArguments[3].Value,
1145                                         (int) (uint) ca.ConstructorArguments[2].Value,
1146                                         (byte) ca.ConstructorArguments[1].Value != 0,
1147                                         (byte) ca.ConstructorArguments[0].Value);
1148
1149                                 return new DecimalConstant (module.Compiler.BuiltinTypes, value, Location.Null);
1150                         }
1151
1152                         return null;
1153                 }
1154
1155                 static Modifiers ReadMethodModifiers (MethodBase mb, TypeSpec declaringType)
1156                 {
1157                         Modifiers mod;
1158                         var ma = mb.Attributes;
1159                         switch (ma & MethodAttributes.MemberAccessMask) {
1160                         case MethodAttributes.Public:
1161                                 mod = Modifiers.PUBLIC;
1162                                 break;
1163                         case MethodAttributes.Assembly:
1164                                 mod = Modifiers.INTERNAL;
1165                                 break;
1166                         case MethodAttributes.Family:
1167                                 mod = Modifiers.PROTECTED;
1168                                 break;
1169                         case MethodAttributes.FamORAssem:
1170                                 mod = Modifiers.PROTECTED | Modifiers.INTERNAL;
1171                                 break;
1172                         default:
1173                                 mod = Modifiers.PRIVATE;
1174                                 break;
1175                         }
1176
1177                         if ((ma & MethodAttributes.Static) != 0) {
1178                                 mod |= Modifiers.STATIC;
1179                                 return mod;
1180                         }
1181                         if ((ma & MethodAttributes.Abstract) != 0 && declaringType.IsClass) {
1182                                 mod |= Modifiers.ABSTRACT;
1183                                 return mod;
1184                         }
1185
1186                         // It can be sealed and override
1187                         if ((ma & MethodAttributes.Final) != 0)
1188                                 mod |= Modifiers.SEALED;
1189
1190                         if ((ma & MethodAttributes.Virtual) != 0) {
1191                                 // Not every member can be detected based on MethodAttribute, we
1192                                 // set virtual or non-virtual only when we are certain. Further checks
1193                                 // to really find out what `virtual' means for this member are done
1194                                 // later
1195                                 if ((ma & MethodAttributes.NewSlot) != 0) {
1196                                         if ((mod & Modifiers.SEALED) != 0) {
1197                                                 mod &= ~Modifiers.SEALED;
1198                                         } else {
1199                                                 mod |= Modifiers.VIRTUAL;
1200                                         }
1201                                 } else {
1202                                         mod |= Modifiers.OVERRIDE;
1203                                 }
1204                         }
1205
1206                         return mod;
1207                 }
1208         }
1209
1210         abstract class ImportedDefinition : IMemberDefinition
1211         {
1212                 protected class AttributesBag
1213                 {
1214                         public static readonly AttributesBag Default = new AttributesBag ();
1215
1216                         public AttributeUsageAttribute AttributeUsage;
1217                         public ObsoleteAttribute Obsolete;
1218                         public string[] Conditionals;
1219                         public string DefaultIndexerName;
1220                         public bool? CLSAttributeValue;
1221                         public TypeSpec CoClass;
1222
1223                         public static AttributesBag Read (MemberInfo mi, MetadataImporter importer)
1224                         {
1225                                 AttributesBag bag = null;
1226                                 List<string> conditionals = null;
1227
1228                                 // It should not throw any loading exception
1229                                 IList<CustomAttributeData> attrs = CustomAttributeData.GetCustomAttributes (mi);
1230
1231                                 string ns, name;
1232                                 foreach (var a in attrs) {
1233                                         importer.GetCustomAttributeTypeName (a, out ns, out name);
1234                                         if (name == "ObsoleteAttribute") {
1235                                                 if (ns != "System")
1236                                                         continue;
1237
1238                                                 if (bag == null)
1239                                                         bag = new AttributesBag ();
1240
1241                                                 var args = a.ConstructorArguments;
1242
1243                                                 if (args.Count == 1) {
1244                                                         bag.Obsolete = new ObsoleteAttribute ((string) args[0].Value);
1245                                                 } else if (args.Count == 2) {
1246                                                         bag.Obsolete = new ObsoleteAttribute ((string) args[0].Value, (bool) args[1].Value);
1247                                                 } else {
1248                                                         bag.Obsolete = new ObsoleteAttribute ();
1249                                                 }
1250
1251                                                 continue;
1252                                         }
1253
1254                                         if (name == "ConditionalAttribute") {
1255                                                 if (ns != "System.Diagnostics")
1256                                                         continue;
1257
1258                                                 if (bag == null)
1259                                                         bag = new AttributesBag ();
1260
1261                                                 if (conditionals == null)
1262                                                         conditionals = new List<string> (2);
1263
1264                                                 conditionals.Add ((string) a.ConstructorArguments[0].Value);
1265                                                 continue;
1266                                         }
1267
1268                                         if (name == "CLSCompliantAttribute") {
1269                                                 if (ns != "System")
1270                                                         continue;
1271
1272                                                 if (bag == null)
1273                                                         bag = new AttributesBag ();
1274
1275                                                 bag.CLSAttributeValue = (bool) a.ConstructorArguments[0].Value;
1276                                                 continue;
1277                                         }
1278
1279                                         // Type only attributes
1280                                         if (mi.MemberType == MemberTypes.TypeInfo || mi.MemberType == MemberTypes.NestedType) {
1281                                                 if (name == "DefaultMemberAttribute") {
1282                                                         if (ns != "System.Reflection")
1283                                                                 continue;
1284
1285                                                         if (bag == null)
1286                                                                 bag = new AttributesBag ();
1287
1288                                                         bag.DefaultIndexerName = (string) a.ConstructorArguments[0].Value;
1289                                                         continue;
1290                                                 }
1291
1292                                                 if (name == "AttributeUsageAttribute") {
1293                                                         if (ns != "System")
1294                                                                 continue;
1295
1296                                                         if (bag == null)
1297                                                                 bag = new AttributesBag ();
1298
1299                                                         bag.AttributeUsage = new AttributeUsageAttribute ((AttributeTargets) a.ConstructorArguments[0].Value);
1300                                                         foreach (var named in a.NamedArguments) {
1301                                                                 if (named.MemberInfo.Name == "AllowMultiple")
1302                                                                         bag.AttributeUsage.AllowMultiple = (bool) named.TypedValue.Value;
1303                                                                 else if (named.MemberInfo.Name == "Inherited")
1304                                                                         bag.AttributeUsage.Inherited = (bool) named.TypedValue.Value;
1305                                                         }
1306                                                         continue;
1307                                                 }
1308
1309                                                 // Interface only attribute
1310                                                 if (name == "CoClassAttribute") {
1311                                                         if (ns != "System.Runtime.InteropServices")
1312                                                                 continue;
1313
1314                                                         if (bag == null)
1315                                                                 bag = new AttributesBag ();
1316
1317                                                         bag.CoClass = importer.ImportType ((MetaType) a.ConstructorArguments[0].Value);
1318                                                         continue;
1319                                                 }
1320                                         }
1321                                 }
1322
1323                                 if (bag == null)
1324                                         return Default;
1325
1326                                 if (conditionals != null)
1327                                         bag.Conditionals = conditionals.ToArray ();
1328
1329                                 return bag;
1330                         }
1331                 }
1332
1333                 protected readonly MemberInfo provider;
1334                 protected AttributesBag cattrs;
1335                 protected readonly MetadataImporter importer;
1336
1337                 public ImportedDefinition (MemberInfo provider, MetadataImporter importer)
1338                 {
1339                         this.provider = provider;
1340                         this.importer = importer;
1341                 }
1342
1343                 #region Properties
1344
1345                 public bool IsImported {
1346                         get {
1347                                 return true;
1348                         }
1349                 }
1350
1351                 public virtual string Name {
1352                         get {
1353                                 return provider.Name;
1354                         }
1355                 }
1356
1357                 #endregion
1358
1359                 public string[] ConditionalConditions ()
1360                 {
1361                         if (cattrs == null)
1362                                 ReadAttributes ();
1363
1364                         return cattrs.Conditionals;
1365                 }
1366
1367                 public ObsoleteAttribute GetAttributeObsolete ()
1368                 {
1369                         if (cattrs == null)
1370                                 ReadAttributes ();
1371
1372                         return cattrs.Obsolete;
1373                 }
1374
1375                 public bool? CLSAttributeValue {
1376                         get {
1377                                 if (cattrs == null)
1378                                         ReadAttributes ();
1379
1380                                 return cattrs.CLSAttributeValue;
1381                         }
1382                 }
1383
1384                 protected void ReadAttributes ()
1385                 {
1386                         cattrs = AttributesBag.Read (provider, importer);
1387                 }
1388
1389                 public void SetIsAssigned ()
1390                 {
1391                         // Unused for imported members
1392                 }
1393
1394                 public void SetIsUsed ()
1395                 {
1396                         // Unused for imported members
1397                 }
1398         }
1399
1400         public class ImportedModuleDefinition
1401         {
1402                 readonly Module module;
1403                 bool cls_compliant;
1404                 readonly MetadataImporter importer;
1405
1406                 public ImportedModuleDefinition (Module module, MetadataImporter importer)
1407                 {
1408                         this.module = module;
1409                         this.importer = importer;
1410                 }
1411
1412                 #region Properties
1413
1414                 public bool IsCLSCompliant {
1415                         get {
1416                                 return cls_compliant;
1417                         }
1418                 }
1419
1420                 public string Name {
1421                         get {
1422                                 return module.Name;
1423                         }
1424                 }
1425
1426                 #endregion
1427
1428                 public void ReadAttributes ()
1429                 {
1430                         IList<CustomAttributeData> attrs = CustomAttributeData.GetCustomAttributes (module);
1431
1432                         string ns, name;
1433                         foreach (var a in attrs) {
1434                                 importer.GetCustomAttributeTypeName (a, out ns, out name);
1435                                 if (name == "CLSCompliantAttribute") {
1436                                         if (ns != "System")
1437                                                 continue;
1438
1439                                         cls_compliant = (bool) a.ConstructorArguments[0].Value;
1440                                         continue;
1441                                 }
1442                         }
1443                 }
1444
1445                 //
1446                 // Reads assembly attributes which where attached to a special type because
1447                 // module does have assembly manifest
1448                 //
1449                 public List<Attribute> ReadAssemblyAttributes ()
1450                 {
1451                         var t = module.GetType (AssemblyAttributesPlaceholder.GetGeneratedName (Name));
1452                         if (t == null)
1453                                 return null;
1454
1455                         var field = t.GetField (AssemblyAttributesPlaceholder.AssemblyFieldName, BindingFlags.NonPublic | BindingFlags.Static);
1456                         if (field == null)
1457                                 return null;
1458
1459                         // TODO: implement, the idea is to fabricate specil Attribute class and
1460                         // add it to OptAttributes before resolving the source code attributes
1461                         // Need to build module location as well for correct error reporting
1462
1463                         //var assembly_attributes = CustomAttributeData.GetCustomAttributes (field);
1464                         //var attrs = new List<Attribute> (assembly_attributes.Count);
1465                         //foreach (var a in assembly_attributes)
1466                         //{
1467                         //    var type = metaImporter.ImportType (a.Constructor.DeclaringType);
1468                         //    var ctor = metaImporter.CreateMethod (a.Constructor, type);
1469
1470                         //    foreach (var carg in a.ConstructorArguments) {
1471                         //        carg.Value
1472                         //    }
1473
1474                         //    attrs.Add (new Attribute ("assembly", ctor, null, Location.Null, true));
1475                         //}
1476
1477                         return null;
1478                 }
1479         }
1480
1481         public class ImportedAssemblyDefinition : IAssemblyDefinition
1482         {
1483                 readonly Assembly assembly;
1484                 readonly AssemblyName aname;
1485                 readonly MetadataImporter importer;
1486                 bool cls_compliant;
1487                 bool contains_extension_methods;
1488
1489                 List<AssemblyName> internals_visible_to;
1490                 Dictionary<IAssemblyDefinition, AssemblyName> internals_visible_to_cache;
1491
1492                 public ImportedAssemblyDefinition (Assembly assembly, MetadataImporter importer)
1493                 {
1494                         this.assembly = assembly;
1495                         this.aname = assembly.GetName ();
1496                         this.importer = importer;
1497                 }
1498
1499                 #region Properties
1500
1501                 public Assembly Assembly {
1502                         get {
1503                                 return assembly;
1504                         }
1505                 }
1506
1507                 public string FullName {
1508                         get {
1509                                 return aname.FullName;
1510                         }
1511                 }
1512
1513                 public bool HasExtensionMethod {
1514                         get {
1515                                 return contains_extension_methods;
1516                         }
1517                 }
1518
1519                 public bool HasStrongName {
1520                         get {
1521                                 return aname.GetPublicKey ().Length != 0;
1522                         }
1523                 }
1524
1525                 public bool IsMissing {
1526                         get {
1527 #if STATIC
1528                                 return assembly.__IsMissing;
1529 #else
1530                                 return false;
1531 #endif
1532                         }
1533                 }
1534
1535                 public bool IsCLSCompliant {
1536                         get {
1537                                 return cls_compliant;
1538                         }
1539                 }
1540
1541                 public string Location {
1542                         get {
1543                                 return assembly.Location;
1544                         }
1545                 }
1546
1547                 public string Name {
1548                         get {
1549                                 return aname.Name;
1550                         }
1551                 }
1552
1553                 #endregion
1554
1555                 public byte[] GetPublicKeyToken ()
1556                 {
1557                         return aname.GetPublicKeyToken ();
1558                 }
1559
1560                 public AssemblyName GetAssemblyVisibleToName (IAssemblyDefinition assembly)
1561                 {
1562                         return internals_visible_to_cache [assembly];
1563                 }
1564
1565                 public bool IsFriendAssemblyTo (IAssemblyDefinition assembly)
1566                 {
1567                         if (internals_visible_to == null)
1568                                 return false;
1569
1570                         AssemblyName is_visible = null;
1571                         if (internals_visible_to_cache == null) {
1572                                 internals_visible_to_cache = new Dictionary<IAssemblyDefinition, AssemblyName> ();
1573                         } else {
1574                                 if (internals_visible_to_cache.TryGetValue (assembly, out is_visible))
1575                                         return is_visible != null;
1576                         }
1577
1578                         var token = assembly.GetPublicKeyToken ();
1579                         if (token != null && token.Length == 0)
1580                                 token = null;
1581
1582                         foreach (var internals in internals_visible_to) {
1583                                 if (internals.Name != assembly.Name)
1584                                         continue;
1585
1586                                 if (token == null && assembly is AssemblyDefinition) {
1587                                         is_visible = internals;
1588                                         break;
1589                                 }
1590
1591                                 if (!ArrayComparer.IsEqual (token, internals.GetPublicKeyToken ()))
1592                                         continue;
1593
1594                                 is_visible = internals;
1595                                 break;
1596                         }
1597
1598                         internals_visible_to_cache.Add (assembly, is_visible);
1599                         return is_visible != null;
1600                 }
1601
1602                 public void ReadAttributes ()
1603                 {
1604 #if STATIC
1605                         if (assembly.__IsMissing)
1606                                 return;
1607 #endif
1608
1609                         IList<CustomAttributeData> attrs = CustomAttributeData.GetCustomAttributes (assembly);
1610
1611                         string ns, name;
1612                         foreach (var a in attrs) {
1613                                 importer.GetCustomAttributeTypeName (a, out ns, out name);
1614
1615                                 if (name == "CLSCompliantAttribute") {
1616                                         if (ns == "System") {
1617                                                 try {
1618                                                         cls_compliant = (bool) a.ConstructorArguments[0].Value;
1619                                                 } catch {
1620                                                 }
1621                                         }
1622                                         continue;
1623                                 }
1624
1625                                 if (name == "InternalsVisibleToAttribute") {
1626                                         if (ns != MetadataImporter.CompilerServicesNamespace)
1627                                                 continue;
1628
1629                                         string s;
1630                                         try {
1631                                                 s = a.ConstructorArguments[0].Value as string;
1632                                         } catch {
1633                                                 s = null;
1634                                         }
1635
1636                                         if (s == null)
1637                                                 continue;
1638
1639                                         var an = new AssemblyName (s);
1640                                         if (internals_visible_to == null)
1641                                                 internals_visible_to = new List<AssemblyName> ();
1642
1643                                         internals_visible_to.Add (an);
1644                                         continue;
1645                                 }
1646
1647                                 if (name == "ExtensionAttribute") {
1648                                         if (ns == MetadataImporter.CompilerServicesNamespace)
1649                                                 contains_extension_methods = true;
1650
1651                                         continue;
1652                                 }
1653                         }
1654                 }
1655
1656                 public override string ToString ()
1657                 {
1658                         return FullName;
1659                 }
1660         }
1661
1662         class ImportedMemberDefinition : ImportedDefinition
1663         {
1664                 readonly TypeSpec type;
1665
1666                 public ImportedMemberDefinition (MemberInfo member, TypeSpec type, MetadataImporter importer)
1667                         : base (member, importer)
1668                 {
1669                         this.type = type;
1670                 }
1671
1672                 #region Properties
1673
1674                 public TypeSpec MemberType {
1675                         get {
1676                                 return type;
1677                         }
1678                 }
1679
1680                 #endregion
1681         }
1682
1683         class ImportedParameterMemberDefinition : ImportedMemberDefinition, IParametersMember
1684         {
1685                 readonly AParametersCollection parameters;
1686
1687                 public ImportedParameterMemberDefinition (MethodBase provider, TypeSpec type, AParametersCollection parameters, MetadataImporter importer)
1688                         : base (provider, type, importer)
1689                 {
1690                         this.parameters = parameters;
1691                 }
1692
1693                 public ImportedParameterMemberDefinition (PropertyInfo provider, TypeSpec type, AParametersCollection parameters, MetadataImporter importer)
1694                         : base (provider, type, importer)
1695                 {
1696                         this.parameters = parameters;
1697                 }
1698
1699                 #region Properties
1700
1701                 public AParametersCollection Parameters {
1702                         get {
1703                                 return parameters;
1704                         }
1705                 }
1706
1707                 #endregion
1708         }
1709
1710         class ImportedGenericMethodDefinition : ImportedParameterMemberDefinition, IGenericMethodDefinition
1711         {
1712                 readonly TypeParameterSpec[] tparams;
1713
1714                 public ImportedGenericMethodDefinition (MethodInfo provider, TypeSpec type, AParametersCollection parameters, TypeParameterSpec[] tparams, MetadataImporter importer)
1715                         : base (provider, type, parameters, importer)
1716                 {
1717                         this.tparams = tparams;
1718                 }
1719
1720                 #region Properties
1721
1722                 public TypeParameterSpec[] TypeParameters {
1723                         get {
1724                                 return tparams;
1725                         }
1726                 }
1727
1728                 public int TypeParametersCount {
1729                         get {
1730                                 return tparams.Length;
1731                         }
1732                 }
1733
1734                 #endregion
1735         }
1736
1737         class ImportedTypeDefinition : ImportedDefinition, ITypeDefinition
1738         {
1739                 TypeParameterSpec[] tparams;
1740                 string name;
1741
1742                 public ImportedTypeDefinition (MetaType type, MetadataImporter importer)
1743                         : base (type, importer)
1744                 {
1745                 }
1746
1747                 #region Properties
1748
1749                 public IAssemblyDefinition DeclaringAssembly {
1750                         get {
1751                                 return importer.GetAssemblyDefinition (provider.Module.Assembly);
1752                         }
1753                 }
1754
1755                 public override string Name {
1756                         get {
1757                                 if (name == null) {
1758                                         name = base.Name;
1759                                         if (tparams != null) {
1760                                                 int arity_start = name.IndexOf ('`');
1761                                                 if (arity_start > 0)
1762                                                         name = name.Substring (0, arity_start);
1763                                         }
1764                                 }
1765
1766                                 return name;
1767                         }
1768                 }
1769
1770                 public string Namespace {
1771                         get {
1772                                 return ((MetaType) provider).Namespace;
1773                         }
1774                 }
1775
1776                 public int TypeParametersCount {
1777                         get {
1778                                 return tparams == null ? 0 : tparams.Length;
1779                         }
1780                 }
1781
1782                 public TypeParameterSpec[] TypeParameters {
1783                         get {
1784                                 return tparams;
1785                         }
1786                         set {
1787                                 tparams = value;
1788                         }
1789                 }
1790
1791                 #endregion
1792
1793                 public static void Error_MissingDependency (IMemberContext ctx, List<TypeSpec> types, Location loc)
1794                 {
1795                         //
1796                         // Report details about missing type and most likely cause of the problem.
1797                         // csc reports 1683, 1684 as warnings but we report them only when used
1798                         // or referenced from the user core in which case compilation error has to
1799                         // be reported because compiler cannot continue anyway
1800                         //
1801                         foreach (var t in types) {
1802                                 string name = t.GetSignatureForError ();
1803
1804                                 if (t.MemberDefinition.DeclaringAssembly == ctx.Module.DeclaringAssembly) {
1805                                         ctx.Module.Compiler.Report.Error (1683, loc,
1806                                                 "Reference to type `{0}' claims it is defined in this assembly, but it is not defined in source or any added modules",
1807                                                 name);
1808                                 } else if (t.MemberDefinition.DeclaringAssembly.IsMissing) {
1809                                         ctx.Module.Compiler.Report.Error (12, loc,
1810                                                 "The type `{0}' is defined in an assembly that is not referenced. Consider adding a reference to assembly `{1}'",
1811                                                 name, t.MemberDefinition.DeclaringAssembly.FullName);
1812                                 } else {
1813                                         ctx.Module.Compiler.Report.Error (1684, loc,
1814                                                 "Reference to type `{0}' claims it is defined assembly `{1}', but it could not be found",
1815                                                 name, t.MemberDefinition.DeclaringAssembly.FullName);
1816                                 }
1817                         }
1818                 }
1819
1820                 public TypeSpec GetAttributeCoClass ()
1821                 {
1822                         if (cattrs == null)
1823                                 ReadAttributes ();
1824
1825                         return cattrs.CoClass;
1826                 }
1827
1828                 public string GetAttributeDefaultMember ()
1829                 {
1830                         if (cattrs == null)
1831                                 ReadAttributes ();
1832
1833                         return cattrs.DefaultIndexerName;
1834                 }
1835
1836                 public AttributeUsageAttribute GetAttributeUsage (PredefinedAttribute pa)
1837                 {
1838                         if (cattrs == null)
1839                                 ReadAttributes ();
1840
1841                         return cattrs.AttributeUsage;
1842                 }
1843
1844                 bool ITypeDefinition.IsInternalAsPublic (IAssemblyDefinition assembly)
1845                 {
1846                         var a = importer.GetAssemblyDefinition (provider.Module.Assembly);
1847                         return a == assembly || a.IsFriendAssemblyTo (assembly);
1848                 }
1849
1850                 public void LoadMembers (TypeSpec declaringType, bool onlyTypes, ref MemberCache cache)
1851                 {
1852                         //
1853                         // Not interested in members of nested private types unless the importer needs them
1854                         //
1855                         if (declaringType.IsPrivate && importer.IgnorePrivateMembers) {
1856                                 cache = MemberCache.Empty;
1857                                 return;
1858                         }
1859
1860                         var loading_type = (MetaType) provider;
1861                         const BindingFlags all_members = BindingFlags.DeclaredOnly |
1862                                 BindingFlags.Static | BindingFlags.Instance |
1863                                 BindingFlags.Public | BindingFlags.NonPublic;
1864
1865                         const MethodAttributes explicit_impl = MethodAttributes.NewSlot |
1866                                         MethodAttributes.Virtual | MethodAttributes.HideBySig |
1867                                         MethodAttributes.Final;
1868
1869                         Dictionary<MethodBase, MethodSpec> possible_accessors = null;
1870                         List<EventSpec> imported_events = null;
1871                         EventSpec event_spec;
1872                         MemberSpec imported;
1873                         MethodInfo m;
1874                         MemberInfo[] all;
1875                         try {
1876                                 all = loading_type.GetMembers (all_members);
1877                         } catch (Exception e) {
1878                                 throw new InternalErrorException (e, "Could not import type `{0}' from `{1}'",
1879                                         declaringType.GetSignatureForError (), declaringType.MemberDefinition.DeclaringAssembly.FullName);
1880                         }
1881
1882                         if (cache == null) {
1883                                 cache = new MemberCache (all.Length);
1884
1885                                 //
1886                                 // Do the types first as they can be referenced by the members before
1887                                 // they are found or inflated
1888                                 //
1889                                 foreach (var member in all) {
1890                                         if (member.MemberType != MemberTypes.NestedType)
1891                                                 continue;
1892
1893                                         var t = (MetaType) member;
1894
1895                                         // Ignore compiler generated types, mostly lambda containers
1896                                         if ((t.Attributes & TypeAttributes.VisibilityMask) == TypeAttributes.NestedPrivate && importer.IgnorePrivateMembers)
1897                                                 continue;
1898
1899                                         imported = importer.CreateNestedType (t, declaringType);
1900                                         cache.AddMemberImported (imported);
1901                                 }
1902
1903                                 foreach (var member in all) {
1904                                         if (member.MemberType != MemberTypes.NestedType)
1905                                                 continue;
1906
1907                                         var t = (MetaType) member;
1908
1909                                         if ((t.Attributes & TypeAttributes.VisibilityMask) == TypeAttributes.NestedPrivate && importer.IgnorePrivateMembers)
1910                                                 continue;
1911
1912                                         importer.ImportTypeBase (t);
1913                                 }
1914                         }
1915
1916                         if (!onlyTypes) {
1917                                 //
1918                                 // The logic here requires methods to be returned first which seems to work for both Mono and .NET
1919                                 //
1920                                 foreach (var member in all) {
1921                                         switch (member.MemberType) {
1922                                         case MemberTypes.Constructor:
1923                                         case MemberTypes.Method:
1924                                                 MethodBase mb = (MethodBase) member;
1925                                                 var attrs = mb.Attributes;
1926
1927                                                 if ((attrs & MethodAttributes.MemberAccessMask) == MethodAttributes.Private) {
1928                                                         if (importer.IgnorePrivateMembers)
1929                                                                 continue;
1930
1931                                                         // Ignore explicitly implemented members
1932                                                         if ((attrs & explicit_impl) == explicit_impl)
1933                                                                 continue;
1934
1935                                                         // Ignore compiler generated methods
1936                                                         if (importer.HasAttribute (CustomAttributeData.GetCustomAttributes (mb), "CompilerGeneratedAttribute", MetadataImporter.CompilerServicesNamespace))
1937                                                                 continue;
1938                                                 }
1939
1940                                                 imported = importer.CreateMethod (mb, declaringType);
1941                                                 if (imported.Kind == MemberKind.Method && !imported.IsGeneric) {
1942                                                         if (possible_accessors == null)
1943                                                                 possible_accessors = new Dictionary<MethodBase, MethodSpec> (ReferenceEquality<MethodBase>.Default);
1944
1945                                                         // There are no metadata rules for accessors, we have to consider any method as possible candidate
1946                                                         possible_accessors.Add (mb, (MethodSpec) imported);
1947                                                 }
1948
1949                                                 break;
1950                                         case MemberTypes.Property:
1951                                                 if (possible_accessors == null)
1952                                                         continue;
1953
1954                                                 var p = (PropertyInfo) member;
1955                                                 //
1956                                                 // Links possible accessors with property
1957                                                 //
1958                                                 MethodSpec get, set;
1959                                                 m = p.GetGetMethod (true);
1960                                                 if (m == null || !possible_accessors.TryGetValue (m, out get))
1961                                                         get = null;
1962
1963                                                 m = p.GetSetMethod (true);
1964                                                 if (m == null || !possible_accessors.TryGetValue (m, out set))
1965                                                         set = null;
1966
1967                                                 // No accessors registered (e.g. explicit implementation)
1968                                                 if (get == null && set == null)
1969                                                         continue;
1970
1971                                                 imported = importer.CreateProperty (p, declaringType, get, set);
1972                                                 if (imported == null)
1973                                                         continue;
1974
1975                                                 break;
1976                                         case MemberTypes.Event:
1977                                                 if (possible_accessors == null)
1978                                                         continue;
1979
1980                                                 var e = (EventInfo) member;
1981                                                 //
1982                                                 // Links accessors with event
1983                                                 //
1984                                                 MethodSpec add, remove;
1985                                                 m = e.GetAddMethod (true);
1986                                                 if (m == null || !possible_accessors.TryGetValue (m, out add))
1987                                                         add = null;
1988
1989                                                 m = e.GetRemoveMethod (true);
1990                                                 if (m == null || !possible_accessors.TryGetValue (m, out remove))
1991                                                         remove = null;
1992
1993                                                 // Both accessors are required
1994                                                 if (add == null || remove == null)
1995                                                         continue;
1996
1997                                                 event_spec = importer.CreateEvent (e, declaringType, add, remove);
1998                                                 if (!importer.IgnorePrivateMembers) {
1999                                                         if (imported_events == null)
2000                                                                 imported_events = new List<EventSpec> ();
2001
2002                                                         imported_events.Add (event_spec);
2003                                                 }
2004
2005                                                 imported = event_spec;
2006                                                 break;
2007                                         case MemberTypes.Field:
2008                                                 var fi = (FieldInfo) member;
2009
2010                                                 imported = importer.CreateField (fi, declaringType);
2011                                                 if (imported == null)
2012                                                         continue;
2013
2014                                                 //
2015                                                 // For dynamic binder event has to be fully restored to allow operations
2016                                                 // within the type container to work correctly
2017                                                 //
2018                                                 if (imported_events != null) {
2019                                                         // The backing event field should be private but it may not
2020                                                         int i;
2021                                                         for (i = 0; i < imported_events.Count; ++i) {
2022                                                                 var ev = imported_events[i];
2023                                                                 if (ev.Name == fi.Name) {
2024                                                                         ev.BackingField = (FieldSpec) imported;
2025                                                                         imported_events.RemoveAt (i);
2026                                                                         i = -1;
2027                                                                         break;
2028                                                                 }
2029                                                         }
2030
2031                                                         if (i < 0)
2032                                                                 continue;
2033                                                 }
2034
2035                                                 break;
2036                                         case MemberTypes.NestedType:
2037                                                 // Already in the cache from the first pass
2038                                                 continue;
2039                                         default:
2040                                                 throw new NotImplementedException (member.ToString ());
2041                                         }
2042
2043                                         cache.AddMemberImported (imported);
2044                                 }
2045                         }
2046
2047                         if (declaringType.IsInterface && declaringType.Interfaces != null) {
2048                                 foreach (var iface in declaringType.Interfaces) {
2049                                         cache.AddInterface (iface);
2050                                 }
2051                         }
2052                 }
2053         }
2054
2055         class ImportedTypeParameterDefinition : ImportedDefinition, ITypeDefinition
2056         {
2057                 public ImportedTypeParameterDefinition (MetaType type, MetadataImporter importer)
2058                         : base (type, importer)
2059                 {
2060                 }
2061
2062                 #region Properties
2063
2064                 public IAssemblyDefinition DeclaringAssembly {
2065                         get {
2066                                 throw new NotImplementedException ();
2067                         }
2068                 }
2069
2070                 public string Namespace {
2071                         get {
2072                                 return null;
2073                         }
2074                 }
2075
2076                 public int TypeParametersCount {
2077                         get {
2078                                 return 0;
2079                         }
2080                 }
2081
2082                 public TypeParameterSpec[] TypeParameters {
2083                         get {
2084                                 return null;
2085                         }
2086                 }
2087
2088                 #endregion
2089
2090                 public TypeSpec GetAttributeCoClass ()
2091                 {
2092                         return null;
2093                 }
2094
2095                 public string GetAttributeDefaultMember ()
2096                 {
2097                         throw new NotSupportedException ();
2098                 }
2099
2100                 public AttributeUsageAttribute GetAttributeUsage (PredefinedAttribute pa)
2101                 {
2102                         throw new NotSupportedException ();
2103                 }
2104
2105                 bool ITypeDefinition.IsInternalAsPublic (IAssemblyDefinition assembly)
2106                 {
2107                         throw new NotImplementedException ();
2108                 }
2109
2110                 public void LoadMembers (TypeSpec declaringType, bool onlyTypes, ref MemberCache cache)
2111                 {
2112                         throw new NotImplementedException ();
2113                 }
2114         }
2115 }