A type parameter can never be optional.
[mono.git] / mcs / gmcs / support.cs
index 522686cb61451b2397a691f135c4178152fc2f26..59989b5b4d40ff2e8e1668e9cfb702c837b530ee 100755 (executable)
@@ -18,8 +18,18 @@ using System.Globalization;
 
 namespace Mono.CSharp {
 
+       public interface GenericConstraints {
+               bool HasConstructor { get; }
+               bool IsReferenceType { get; }
+               bool IsValueType { get; }
+               bool HasClassConstraint { get; }
+               Type ClassConstraint { get; }
+               Type[] InterfaceConstraints { get; }
+       }
+
        public interface ParameterData {
                Type ParameterType (int pos);
+               GenericConstraints GenericConstraints (int pos);
                bool HasArrayParameter { get; }
                int  Count { get; }
                string ParameterName (int pos);
@@ -30,32 +40,34 @@ namespace Mono.CSharp {
        public class ReflectionParameters : ParameterData {
                ParameterInfo [] pi;
                bool last_arg_is_params = false;
-               
+               ParameterData gpd;
+
                public ReflectionParameters (MethodBase method)
                {
                        object [] attrs;
-                       
+
                        this.pi = method.GetParameters ();
                        int count = pi.Length-1;
 
                        if (count < 0)
                                return;
 
-                       if (method.HasGenericParameters) {
+                       if (method.Mono_IsInflatedMethod) {
                                MethodInfo generic = method.GetGenericMethodDefinition ();
-                               ParameterData gpd = Invocation.GetParameterData (generic);
+                               gpd = Invocation.GetParameterData (generic);
 
                                last_arg_is_params = gpd.HasArrayParameter;
-                       } else {
-                               attrs = pi [count].GetCustomAttributes (TypeManager.param_array_type, true);
-                               if (attrs == null)
-                                       return;
-                               
-                               if (attrs.Length == 0)
-                                       return;
-
-                               last_arg_is_params = true;
+                               return;
                        }
+
+                       attrs = pi [count].GetCustomAttributes (TypeManager.param_array_type, true);
+                       if (attrs == null)
+                               return;
+
+                       if (attrs.Length == 0)
+                               return;
+
+                       last_arg_is_params = true;
                }
 
                public bool HasArrayParameter {
@@ -73,6 +85,18 @@ namespace Mono.CSharp {
                        }
                }
 
+               public GenericConstraints GenericConstraints (int pos)
+               {
+                       if (gpd != null)
+                               return gpd.GenericConstraints (pos);
+
+                       Type t = ParameterType (pos);
+                       if (!t.IsGenericParameter)
+                               return null;
+
+                       return ReflectionConstraints.Create (t);
+               }
+
                public string ParameterName (int pos)
                {
                        if (last_arg_is_params && pos >= pi.Length - 1)
@@ -130,7 +154,67 @@ namespace Mono.CSharp {
                                return pi.Length;
                        }
                }
-               
+
+               protected class ReflectionConstraints : GenericConstraints
+               {
+                       bool has_ctor;
+                       bool is_reference_type;
+                       bool is_value_type;
+                       Type class_constraint;
+                       Type[] iface_constraints;
+
+                       protected ReflectionConstraints (bool has_ctor, Type class_constr,
+                                                        Type[] iface_constrs)
+                       {
+                               this.has_ctor = has_ctor;
+                               this.class_constraint = class_constr;
+                               this.iface_constraints = iface_constrs;
+
+                               if (class_constraint != null) {
+                                       if (class_constraint == TypeManager.object_type)
+                                               is_reference_type = true;
+                                       else if (class_constraint == TypeManager.value_type)
+                                               is_value_type = true;
+                               }
+                       }
+
+                       public static GenericConstraints Create (Type t)
+                       {
+                               Type class_constr = null;
+                               Type[] iface_constrs = t.GetInterfaces ();
+                               if (iface_constrs ==  null)
+                                       iface_constrs = Type.EmptyTypes;
+                               if (t.BaseType != TypeManager.object_type)
+                                       class_constr = t.BaseType;
+
+                               return new ReflectionConstraints (
+                                       false, class_constr, iface_constrs);
+                       }
+
+                       public bool HasConstructor {
+                               get { return has_ctor; }
+                       }
+
+                       public bool HasClassConstraint {
+                               get { return class_constraint != null; }
+                       }
+
+                       public bool IsReferenceType {
+                               get { return is_reference_type; }
+                       }
+
+                       public bool IsValueType {
+                               get { return is_value_type; }
+                       }
+
+                       public Type ClassConstraint {
+                               get { return class_constraint; }
+                       }
+
+                       public Type[] InterfaceConstraints {
+                               get { return iface_constraints; }
+                       }
+               }
        }
 
        public class InternalParameters : ParameterData {
@@ -182,6 +266,13 @@ namespace Mono.CSharp {
                        return GetParameter (pos).ExternalType ();
                }
 
+               public GenericConstraints GenericConstraints (int pos)
+               {
+                       if (param_types == null)
+                               return null;
+
+                       return GetParameter (pos).GenericConstraints;
+               }
 
                public string ParameterName (int pos)
                {
@@ -328,6 +419,42 @@ namespace Mono.CSharp {
                {
                        this.reader = reader;
                        this.buffer = new char [DefaultCacheSize];
+                       
+                       // Compute the preamble size
+                       
+                       // Let the StreamWriter autodetect the encoder
+                       reader.Peek ();
+                       
+                       reader.BaseStream.Position = 0;
+                       Encoding enc = reader.CurrentEncoding;
+                       // First of all, get at least a char
+                       
+                       byte[] auxb = new byte [50];
+                       int num_bytes = 0;
+                       int num_chars = 0;
+                       int br = 0;
+                       do {
+                               br = reader.BaseStream.Read (auxb, num_bytes, auxb.Length - num_bytes);
+                               num_bytes += br;
+                               num_chars = enc.GetCharCount (auxb, 0, num_bytes);
+                       }
+                       while (num_chars == 0 && br > 0);
+                       
+                       if (num_chars != 0)
+                       {
+                               // Now, check which bytes at the beginning have no effect in the
+                               // char count
+                               
+                               int p = 0;
+                               while (enc.GetCharCount (auxb, p, num_bytes-p) >= num_chars)
+                                       p++;
+                               
+                               preamble_size = p - 1;
+                               reader.BaseStream.Position = 0;
+                               reader.DiscardBufferedData ();
+                               
+                               buffer_start = preamble_size;
+                       }
                }
 
                public SeekableStreamReader (Stream stream, Encoding encoding, bool detect_encoding_from_bytemarks)
@@ -343,6 +470,7 @@ namespace Mono.CSharp {
                int buffer_size;        // in bytes
                int char_count;         // count buffer[] valid characters
                int pos;                // index into buffer[]
+               int preamble_size;
 
                /// <remarks>
                ///   The difference to the StreamReader's BaseStream.Position is that this one is reliable; ie. it
@@ -365,6 +493,9 @@ namespace Mono.CSharp {
                                        
                                        return;
                                }
+                               
+                               if (value == 0) // Skip preamble
+                                       value = preamble_size;
 
                                // Ok, now we need to seek.
                                reader.DiscardBufferedData ();