source: branches/2389-EpsLexicase/HeuristicLab.ExtLibs/HeuristicLab.NRefactory/5.5.0/NRefactory.CSharp-5.5.0/Parser/mcs/report.cs

//
// report.cs: report errors and warnings.
//
// Author: Miguel de Icaza (miguel@ximian.com)
//         Marek Safar (marek.safar@gmail.com)         
//
// Copyright 2001 Ximian, Inc. (http://www.ximian.com)
// Copyright 2011 Xamarin, Inc (http://www.xamarin.com)
//

using System;
using System.IO;
using System.Text;
using System.Collections.Generic;
using System.Diagnostics;

namespace Mono.CSharp {

  //
  // Errors and warnings manager
  //
  public class Report
  {
    public const int RuntimeErrorId = 10000;

    Dictionary<int, WarningRegions> warning_regions_table;

    ReportPrinter printer;

    int reporting_disabled;

    readonly CompilerSettings settings;
    
    /// <summary>
    /// List of symbols related to reported error/warning. You have to fill it before error/warning is reported.
    /// </summary>
    List<string> extra_information = new List<string> ();

    // 
    // IF YOU ADD A NEW WARNING YOU HAVE TO ADD ITS ID HERE
    //
    public static readonly int[] AllWarnings = new int[] {
      28, 67, 78,
      105, 108, 109, 114, 162, 164, 168, 169, 183, 184, 197,
      219, 251, 252, 253, 278, 282,
      402, 414, 419, 420, 429, 436, 437, 440, 458, 464, 465, 467, 469, 472, 473,
      612, 618, 626, 628, 642, 649, 652, 657, 658, 659, 660, 661, 665, 672, 675, 693,
      728,
      809, 824,
      1030, 1058, 1060, 1066,
      1522, 1570, 1571, 1572, 1573, 1574, 1580, 1581, 1584, 1587, 1589, 1590, 1591, 1592,
      1607, 1616, 1633, 1634, 1635, 1685, 1690, 1691, 1692, 1695, 1696, 1697, 1699,
      1700, 1701, 1702, 1709, 1711, 1717, 1718, 1720, 1735,
      1901, 1956, 1981, 1998,
      2002, 2023, 2029,
      3000, 3001, 3002, 3003, 3005, 3006, 3007, 3008, 3009,
      3010, 3011, 3012, 3013, 3014, 3015, 3016, 3017, 3018, 3019,
      3021, 3022, 3023, 3024, 3026, 3027,
      4014, 4024, 4025, 4026,
      7035, 7080, 7081, 7082, 7095,
      8009,
    };

    static HashSet<int> AllWarningsHashSet;

    public Report (CompilerContext context, ReportPrinter printer)
    {
      if (context == null)
        throw new ArgumentNullException ("settings");
      if (printer == null)
        throw new ArgumentNullException ("printer");

      this.settings = context.Settings;
      this.printer = printer;
    }

    public void DisableReporting ()
    {
      ++reporting_disabled;
    }

    public void EnableReporting ()
    {
      --reporting_disabled;
    }

    public void FeatureIsNotAvailable (CompilerContext compiler, Location loc, string feature)
    {
      string version;
      switch (compiler.Settings.Version) {
      case LanguageVersion.ISO_1:
        version = "1.0";
        break;
      case LanguageVersion.ISO_2:
        version = "2.0";
        break;
      case LanguageVersion.V_3:
        version = "3.0";
        break;
      case LanguageVersion.V_4:
        version = "4.0";
        break;
      case LanguageVersion.V_5:
        version = "5.0";
        break;
      case LanguageVersion.V_6:
        version = "6.0";
        break;
      default:
        throw new InternalErrorException ("Invalid feature version", compiler.Settings.Version);
      }

      Error (1644, loc,
        "Feature `{0}' cannot be used because it is not part of the C# {1} language specification",
              feature, version);
    }

    public void FeatureIsNotSupported (Location loc, string feature)
    {
      Error (1644, loc,
        "Feature `{0}' is not supported in Mono mcs1 compiler. Consider using the `gmcs' compiler instead",
        feature);
    }
            
    public void RuntimeMissingSupport (Location loc, string feature) 
    {
      Error (-88, loc, "Your .NET Runtime does not support `{0}'. Please use the latest Mono runtime instead.", feature);
    }

    /// <summary>
    /// In most error cases is very useful to have information about symbol that caused the error.
    /// Call this method before you call Report.Error when it makes sense.
    /// </summary>
    public void SymbolRelatedToPreviousError (Location loc, string symbol)
    {
      SymbolRelatedToPreviousError (loc.ToString ());
    }

    public void SymbolRelatedToPreviousError (MemberSpec ms)
    {
      if (reporting_disabled > 0 || !printer.HasRelatedSymbolSupport)
        return;

      var mc = ms.MemberDefinition as MemberCore;
      while (ms is ElementTypeSpec) {
        ms = ((ElementTypeSpec) ms).Element;
        mc = ms.MemberDefinition as MemberCore;
      }

      if (mc != null) {
        SymbolRelatedToPreviousError (mc);
      } else {
        if (ms.DeclaringType != null)
          ms = ms.DeclaringType;

        var imported_type = ms.MemberDefinition as ImportedTypeDefinition;
        if (imported_type != null) {
          var iad = imported_type.DeclaringAssembly as ImportedAssemblyDefinition;
          SymbolRelatedToPreviousError (iad.Location);
        }
      }
    }

    public void SymbolRelatedToPreviousError (MemberCore mc)
    {
      SymbolRelatedToPreviousError (mc.Location, mc.GetSignatureForError ());
    }

    public void SymbolRelatedToPreviousError (string loc)
    {
      string msg = String.Format ("{0} (Location of the symbol related to previous ", loc);
      if (extra_information.Contains (msg))
        return;

      extra_information.Add (msg);
    }

    public bool CheckWarningCode (int code, Location loc)
    {
      if (AllWarningsHashSet == null)
        AllWarningsHashSet = new HashSet<int> (AllWarnings);

      if (AllWarningsHashSet.Contains (code))
        return true;

      Warning (1691, 1, loc, "`{0}' is not a valid warning number", code);
      return false;
    }

    public void ExtraInformation (Location loc, string msg)
    {
      extra_information.Add (String.Format ("{0} {1}", loc, msg));
    }

    public WarningRegions RegisterWarningRegion (Location location)
    {
      WarningRegions regions;
      if (warning_regions_table == null) {
        regions = null;
        warning_regions_table = new Dictionary<int, WarningRegions> ();
      } else {
        warning_regions_table.TryGetValue (location.File, out regions);
      }

      if (regions == null) {
        regions = new WarningRegions ();
        warning_regions_table.Add (location.File, regions);
      }

      return regions;
    }

    public void Warning (int code, int level, Location loc, string message)
    {
      if (reporting_disabled > 0)
        return;

      if (!settings.IsWarningEnabled (code, level))
        return;

      if (warning_regions_table != null && !loc.IsNull) {
        WarningRegions regions;
        if (warning_regions_table.TryGetValue (loc.File, out regions) && !regions.IsWarningEnabled (code, loc.Row))
          return;
      }

      AbstractMessage msg;
      if (settings.IsWarningAsError (code)) {
        message = "Warning as Error: " + message;
        msg = new ErrorMessage (code, loc, message, extra_information);
      } else {
        msg = new WarningMessage (code, loc, message, extra_information);
      }

      extra_information.Clear ();
      printer.Print (msg, settings.ShowFullPaths);
    }

    public void Warning (int code, int level, Location loc, string format, string arg)
    {
      Warning (code, level, loc, String.Format (format, arg));
    }

    public void Warning (int code, int level, Location loc, string format, string arg1, string arg2)
    {
      Warning (code, level, loc, String.Format (format, arg1, arg2));
    }

    public void Warning (int code, int level, Location loc, string format, params object[] args)
    {
      Warning (code, level, loc, String.Format (format, args));
    }

    public void Warning (int code, int level, string message)
    {
      Warning (code, level, Location.Null, message);
    }

    public void Warning (int code, int level, string format, string arg)
    {
      Warning (code, level, Location.Null, format, arg);
    }

    public void Warning (int code, int level, string format, string arg1, string arg2)
    {
      Warning (code, level, Location.Null, format, arg1, arg2);
    }

    public void Warning (int code, int level, string format, params string[] args)
    {
      Warning (code, level, Location.Null, String.Format (format, args));
    }

    //
    // Warnings encountered so far
    //
    public int Warnings {
      get { return printer.WarningsCount; }
    }

    public void Error (int code, Location loc, string error)
    {
      if (reporting_disabled > 0)
        return;

      ErrorMessage msg = new ErrorMessage (code, loc, error, extra_information);
      extra_information.Clear ();

      printer.Print (msg, settings.ShowFullPaths);

      if (settings.Stacktrace)
        Console.WriteLine (FriendlyStackTrace (new StackTrace (true)));

      if (printer.ErrorsCount == settings.FatalCounter)
        throw new FatalException (msg.Text);
    }

    public void Error (int code, Location loc, string format, string arg)
    {
      Error (code, loc, String.Format (format, arg));
    }

    public void Error (int code, Location loc, string format, string arg1, string arg2)
    {
      Error (code, loc, String.Format (format, arg1, arg2));
    }

    public void Error (int code, Location loc, string format, params string[] args)
    {
      Error (code, loc, String.Format (format, args));
    }

    public void Error (int code, string error)
    {
      Error (code, Location.Null, error);
    }

    public void Error (int code, string format, string arg)
    {
      Error (code, Location.Null, format, arg);
    }

    public void Error (int code, string format, string arg1, string arg2)
    {
      Error (code, Location.Null, format, arg1, arg2);
    }

    public void Error (int code, string format, params string[] args)
    {
      Error (code, Location.Null, String.Format (format, args));
    }

    //
    // Errors encountered so far
    //
    public int Errors {
      get { return printer.ErrorsCount; }
    }

    public bool IsDisabled {
      get {
        return reporting_disabled > 0;
      }
    }

    public ReportPrinter Printer {
      get { return printer; }
    }

    public ReportPrinter SetPrinter (ReportPrinter printer)
    {
      ReportPrinter old = this.printer;
      this.printer = printer;
      return old;
    }

    [Conditional ("MCS_DEBUG")]
    static public void Debug (string message, params object[] args)
    {
      Debug (4, message, args);
    }
      
    [Conditional ("MCS_DEBUG")]
    static public void Debug (int category, string message, params object[] args)
    {
//      if ((category & DebugFlags) == 0)
//        return;

      StringBuilder sb = new StringBuilder (message);

      if ((args != null) && (args.Length > 0)) {
        sb.Append (": ");

        bool first = true;
        foreach (object arg in args) {
          if (first)
            first = false;
          else
            sb.Append (", ");
          if (arg == null)
            sb.Append ("null");
//          else if (arg is ICollection)
//            sb.Append (PrintCollection ((ICollection) arg));
          else
            sb.Append (arg);
        }
      }

      Console.WriteLine (sb.ToString ());
    }
/*
    static public string PrintCollection (ICollection collection)
    {
      StringBuilder sb = new StringBuilder ();

      sb.Append (collection.GetType ());
      sb.Append ("(");

      bool first = true;
      foreach (object o in collection) {
        if (first)
          first = false;
        else
          sb.Append (", ");
        sb.Append (o);
      }

      sb.Append (")");
      return sb.ToString ();
    }
*/
    static string FriendlyStackTrace (StackTrace t)
    {
      StringBuilder sb = new StringBuilder ();

      bool foundUserCode = false;

      for (int i = 0; i < t.FrameCount; i++) {
        StackFrame f = t.GetFrame (i);
        var mb = f.GetMethod ();

        if (!foundUserCode && mb.ReflectedType == typeof (Report))
          continue;

        foundUserCode = true;

        sb.Append ("\tin ");

        if (f.GetFileLineNumber () > 0)
          sb.AppendFormat ("(at {0}:{1}) ", f.GetFileName (), f.GetFileLineNumber ());

        sb.AppendFormat ("{0}.{1} (", mb.ReflectedType.Name, mb.Name);

        bool first = true;
        foreach (var pi in mb.GetParameters ()) {
          if (!first)
            sb.Append (", ");
          first = false;

          sb.Append (pi.ParameterType.FullName);
        }
        sb.Append (")\n");
      }

      return sb.ToString ();
    }
  }

  public abstract class AbstractMessage
  {
    readonly string[] extra_info;
    protected readonly int code;
    protected readonly Location location;
    readonly string message;

    protected AbstractMessage (int code, Location loc, string msg, List<string> extraInfo)
    {
      this.code = code;
      if (code < 0)
        this.code = 8000 - code;

      this.location = loc;
      this.message = msg;
      if (extraInfo.Count != 0) {
        this.extra_info = extraInfo.ToArray ();
      }
    }

    protected AbstractMessage (AbstractMessage aMsg)
    {
      this.code = aMsg.code;
      this.location = aMsg.location;
      this.message = aMsg.message;
      this.extra_info = aMsg.extra_info;
    }

    public int Code {
      get { return code; }
    }

    public override bool Equals (object obj)
    {
      AbstractMessage msg = obj as AbstractMessage;
      if (msg == null)
        return false;

      return code == msg.code && location.Equals (msg.location) && message == msg.message;
    }

    public override int GetHashCode ()
    {
      return code.GetHashCode ();
    }

    public abstract bool IsWarning { get; }

    public Location Location {
      get { return location; }
    }

    public abstract string MessageType { get; }

    public string[] RelatedSymbols {
      get { return extra_info; }
    }

    public string Text {
      get { return message; }
    }
  }

  sealed class WarningMessage : AbstractMessage
  {
    public WarningMessage (int code, Location loc, string message, List<string> extra_info)
      : base (code, loc, message, extra_info)
    {
    }

    public override bool IsWarning {
      get { return true; }
    }

    public override string MessageType {
      get {
        return "warning";
      }
    }
  }

  sealed class ErrorMessage : AbstractMessage
  {
    public ErrorMessage (int code, Location loc, string message, List<string> extraInfo)
      : base (code, loc, message, extraInfo)
    {
    }

    public ErrorMessage (AbstractMessage aMsg)
      : base (aMsg)
    {
    }

    public override bool IsWarning {
      get { return false; }
    }

    public override string MessageType {
      get {
        return "error";
      }
    }
  }

  //
  // Generic base for any message writer
  //
  public abstract class ReportPrinter
  {
    protected HashSet<ITypeDefinition> reported_missing_definitions;

    #region Properties

    public int ErrorsCount { get; protected set; }
    
    public int WarningsCount { get; private set; }
  
    //
    // When (symbols related to previous ...) can be used
    //
    public virtual bool HasRelatedSymbolSupport {
      get { return true; }
    }

    #endregion


    protected virtual string FormatText (string txt)
    {
      return txt;
    }

    public virtual void Print (AbstractMessage msg, bool showFullPath)
    {
      if (msg.IsWarning) {
        ++WarningsCount;
      } else {
        ++ErrorsCount;
      }
    }

    protected void Print (AbstractMessage msg, TextWriter output, bool showFullPath)
    {
      StringBuilder txt = new StringBuilder ();
      if (!msg.Location.IsNull) {
        if (showFullPath)
          txt.Append (msg.Location.ToStringFullName ());
        else
          txt.Append (msg.Location.ToString ());

        txt.Append (" ");
      }

      txt.AppendFormat ("{0} CS{1:0000}: {2}", msg.MessageType, msg.Code, msg.Text);

      if (!msg.IsWarning)
        output.WriteLine (FormatText (txt.ToString ()));
      else
        output.WriteLine (txt.ToString ());

      if (msg.RelatedSymbols != null) {
        foreach (string s in msg.RelatedSymbols)
          output.WriteLine (s + msg.MessageType + ")");
      }
    }

    //
    // Tracks reported missing types. It needs to be session specific 
    // because we can run in probing mode
    //
    public bool MissingTypeReported (ITypeDefinition typeDefinition)
    {
      if (reported_missing_definitions == null)
        reported_missing_definitions = new HashSet<ITypeDefinition> ();

      if (reported_missing_definitions.Contains (typeDefinition))
        return true;

      reported_missing_definitions.Add (typeDefinition);
      return false;
    }

    public void Reset ()
    {
      // HACK: Temporary hack for broken repl flow
      ErrorsCount = WarningsCount = 0;
    }
  }

  sealed class NullReportPrinter : ReportPrinter
  {
  }

  //
  // Default message recorder, it uses two types of message groups.
  // Common messages: messages reported in all sessions.
  // Merged messages: union of all messages in all sessions. 
  //
  // Used by the Lambda expressions to compile the code with various
  // parameter values, or by attribute resolver
  //
  class SessionReportPrinter : ReportPrinter
  {
    List<AbstractMessage> session_messages;
    //
    // A collection of exactly same messages reported in all sessions
    //
    List<AbstractMessage> common_messages;

    //
    // A collection of unique messages reported in all sessions
    //
    List<AbstractMessage> merged_messages;

    bool showFullPaths;

    public void ClearSession ()
    {
      session_messages = null;
    }

    public override void Print (AbstractMessage msg, bool showFullPath)
    {
      //
      // This line is useful when debugging recorded messages
      //
      // Console.WriteLine ("RECORDING: {0}", msg.Text);

      if (session_messages == null)
        session_messages = new List<AbstractMessage> ();

      session_messages.Add (msg);

      this.showFullPaths = showFullPath;
      base.Print (msg, showFullPath);
    }

    public void EndSession ()
    {
      if (session_messages == null)
        return;

      //
      // Handles the first session
      //
      if (common_messages == null) {
        common_messages = new List<AbstractMessage> (session_messages);
        merged_messages = session_messages;
        session_messages = null;
        return;
      }

      //
      // Store common messages if any
      //
      for (int i = 0; i < common_messages.Count; ++i) {
        AbstractMessage cmsg = common_messages[i];
        bool common_msg_found = false;
        foreach (AbstractMessage msg in session_messages) {
          if (cmsg.Equals (msg)) {
            common_msg_found = true;
            break;
          }
        }

        if (!common_msg_found)
          common_messages.RemoveAt (i);
      }

      //
      // Merge session and previous messages
      //
      for (int i = 0; i < session_messages.Count; ++i) {
        AbstractMessage msg = session_messages[i];
        bool msg_found = false;
        for (int ii = 0; ii < merged_messages.Count; ++ii) {
          if (msg.Equals (merged_messages[ii])) {
            msg_found = true;
            break;
          }
        }

        if (!msg_found)
          merged_messages.Add (msg);
      }
    }

    public bool IsEmpty {
      get {
        return merged_messages == null && common_messages == null;
      }
    }

    //
    // Prints collected messages, common messages have a priority
    //
    public bool Merge (ReportPrinter dest)
    {
      var messages_to_print = merged_messages;
      if (common_messages != null && common_messages.Count > 0) {
        messages_to_print = common_messages;
      }

      if (messages_to_print == null)
        return false;

      bool error_msg = false;
      foreach (AbstractMessage msg in messages_to_print) {
        dest.Print (msg, showFullPaths);
        error_msg |= !msg.IsWarning;
      }

      if (reported_missing_definitions != null) {
        foreach (var missing in reported_missing_definitions)
          dest.MissingTypeReported (missing);
      }

      return error_msg;
    }
  }

  public class StreamReportPrinter : ReportPrinter
  {
    readonly TextWriter writer;

    public StreamReportPrinter (TextWriter writer)
    {
      this.writer = writer;
    }

    public override void Print (AbstractMessage msg, bool showFullPath)
    {
      Print (msg, writer, showFullPath);
      base.Print (msg, showFullPath);
    }
  }

  public class ConsoleReportPrinter : StreamReportPrinter
  {
    static readonly string prefix, postfix;

    static ConsoleReportPrinter ()
    {
      string term = Environment.GetEnvironmentVariable ("TERM");
      bool xterm_colors = false;
      
      switch (term){
      case "xterm":
      case "rxvt":
      case "rxvt-unicode": 
        if (Environment.GetEnvironmentVariable ("COLORTERM") != null){
          xterm_colors = true;
        }
        break;

      case "xterm-color":
      case "xterm-256color":
        xterm_colors = true;
        break;
      }
      if (!xterm_colors)
        return;

      if (!(UnixUtils.isatty (1) && UnixUtils.isatty (2)))
        return;
      
      string config = Environment.GetEnvironmentVariable ("MCS_COLORS");
      if (config == null){
        config = "errors=red";
        //config = "brightwhite,red";
      }

      if (config == "disable")
        return;

      if (!config.StartsWith ("errors="))
        return;

      config = config.Substring (7);
      
      int p = config.IndexOf (",");
      if (p == -1)
        prefix = GetForeground (config);
      else
        prefix = GetBackground (config.Substring (p+1)) + GetForeground (config.Substring (0, p));
      postfix = "\x001b[0m";
    }

    public ConsoleReportPrinter ()
      : base (Console.Error)
    {
    }

    public ConsoleReportPrinter (TextWriter writer)
      : base (writer)
    {
    }

    static int NameToCode (string s)
    {
      switch (s) {
      case "black":
        return 0;
      case "red":
        return 1;
      case "green":
        return 2;
      case "yellow":
        return 3;
      case "blue":
        return 4;
      case "magenta":
        return 5;
      case "cyan":
        return 6;
      case "grey":
      case "white":
        return 7;
      }
      return 7;
    }

    //
    // maps a color name to its xterm color code
    //
    static string GetForeground (string s)
    {
      string highcode;

      if (s.StartsWith ("bright")) {
        highcode = "1;";
        s = s.Substring (6);
      } else
        highcode = "";

      return "\x001b[" + highcode + (30 + NameToCode (s)).ToString () + "m";
    }

    static string GetBackground (string s)
    {
      return "\x001b[" + (40 + NameToCode (s)).ToString () + "m";
    }

    protected override string FormatText (string txt)
    {
      if (prefix != null)
        return prefix + txt + postfix;

      return txt;
    }
  }

  class TimeReporter
  {
    public enum TimerType
    {
      ParseTotal,
      AssemblyBuilderSetup,
      CreateTypeTotal,
      ReferencesLoading,
      ReferencesImporting,
      PredefinedTypesInit,
      ModuleDefinitionTotal,
      EmitTotal,
      CloseTypes,
      Resouces,
      OutputSave,
      DebugSave,
    }

    readonly Stopwatch[] timers;
    Stopwatch total;

    public TimeReporter (bool enabled)
    {
      if (!enabled)
        return;

      timers = new Stopwatch[System.Enum.GetValues(typeof (TimerType)).Length];
    }

    public void Start (TimerType type)
    {
      if (timers != null) {
        var sw = new Stopwatch ();
        timers[(int) type] = sw;
        sw.Start ();
      }
    }

    public void StartTotal ()
    {
      total = new Stopwatch ();
      total.Start ();
    }

    public void Stop (TimerType type)
    {
      if (timers != null) {
        timers[(int) type].Stop ();
      }
    }

    public void StopTotal ()
    {
      total.Stop ();
    }

    public void ShowStats ()
    {
      if (timers == null)
        return;

      Dictionary<TimerType, string> timer_names = new Dictionary<TimerType,string> {
        { TimerType.ParseTotal, "Parsing source files" },
        { TimerType.AssemblyBuilderSetup, "Assembly builder setup" },
        { TimerType.CreateTypeTotal, "Compiled types created" },
        { TimerType.ReferencesLoading, "Referenced assemblies loading" },
        { TimerType.ReferencesImporting, "Referenced assemblies importing" },
        { TimerType.PredefinedTypesInit, "Predefined types initialization" },
        { TimerType.ModuleDefinitionTotal, "Module definition" },
        { TimerType.EmitTotal, "Resolving and emitting members blocks" },
        { TimerType.CloseTypes, "Module types closed" },
        { TimerType.Resouces, "Embedding resources" },
        { TimerType.OutputSave, "Writing output file" },
        { TimerType.DebugSave, "Writing debug symbols file" },
      };

      int counter = 0;
      double percentage = (double) total.ElapsedMilliseconds / 100;
      long subtotal = total.ElapsedMilliseconds;
      foreach (var timer in timers) {
        string msg = timer_names[(TimerType) counter++];
        var ms = timer == null ? 0 : timer.ElapsedMilliseconds;
        Console.WriteLine ("{0,4:0.0}% {1,5}ms {2}", ms / percentage, ms, msg);
        subtotal -= ms;
      }

      Console.WriteLine ("{0,4:0.0}% {1,5}ms Other tasks", subtotal / percentage, subtotal);
      Console.WriteLine ();
      Console.WriteLine ("Total elapsed time: {0}", total.Elapsed);
    }
  }

  public class InternalErrorException : Exception {
    public InternalErrorException (MemberCore mc, Exception e)
      : base (mc.Location + " " + mc.GetSignatureForError (), e)
    {
    }

    public InternalErrorException ()
      : base ("Internal error")
    {
    }

    public InternalErrorException (string message)
      : base (message)
    {
    }

    public InternalErrorException (string message, params object[] args)
      : base (String.Format (message, args))
    {
    }

    public InternalErrorException (Exception exception, string message, params object[] args)
      : base (String.Format (message, args), exception)
    {
    }
    
    public InternalErrorException (Exception e, Location loc)
      : base (loc.ToString (), e)
    {
    }
  }

  class FatalException : Exception
  {
    public FatalException (string message)
      : base (message)
    {
    }
  }

  /// <summary>
  /// Handles #pragma warning
  /// </summary>
  public class WarningRegions {

    abstract class PragmaCmd
    {
      public int Line;

      protected PragmaCmd (int line)
      {
        Line = line;
      }

      public abstract bool IsEnabled (int code, bool previous);
    }
    
    class Disable : PragmaCmd
    {
      int code;
      public Disable (int line, int code)
        : base (line)
      {
        this.code = code;
      }

      public override bool IsEnabled (int code, bool previous)
      {
        return this.code != code && previous;
      }
    }

    class DisableAll : PragmaCmd
    {
      public DisableAll (int line)
        : base (line) {}

      public override bool IsEnabled(int code, bool previous)
      {
        return false;
      }
    }

    class Enable : PragmaCmd
    {
      int code;
      public Enable (int line, int code)
        : base (line)
      {
        this.code = code;
      }

      public override bool IsEnabled(int code, bool previous)
      {
        return this.code == code || previous;
      }
    }

    class EnableAll : PragmaCmd
    {
      public EnableAll (int line)
        : base (line) {}

      public override bool IsEnabled(int code, bool previous)
      {
        return true;
      }
    }


    List<PragmaCmd> regions = new List<PragmaCmd> ();

    public void WarningDisable (int line)
    {
      regions.Add (new DisableAll (line));
    }

    public void WarningDisable (Location location, int code, Report Report)
    {
      if (Report.CheckWarningCode (code, location))
        regions.Add (new Disable (location.Row, code));
    }

    public void WarningEnable (int line)
    {
      regions.Add (new EnableAll (line));
    }

    public void WarningEnable (Location location, int code, CompilerContext context)
    {
      if (!context.Report.CheckWarningCode (code, location))
        return;

      if (context.Settings.IsWarningDisabledGlobally (code))
        context.Report.Warning (1635, 1, location, "Cannot restore warning `CS{0:0000}' because it was disabled globally", code);

      regions.Add (new Enable (location.Row, code));
    }

    public bool IsWarningEnabled (int code, int src_line)
    {
      bool result = true;
      foreach (PragmaCmd pragma in regions) {
        if (src_line < pragma.Line)
          break;

        result = pragma.IsEnabled (code, result);
      }
      return result;
    }
  }
}