System.Data.SQLite

            int u = arAtt.Length;
            for (int y = 0; y < u; y++)
            {
              at = arAtt[y] as SQLiteFunctionAttribute;
              if (at != null)
              {
                at.InstanceType = arTypes[x];
                ReplaceFunction(at, null);
              }
            }
          }
        }
#endif
      }
      catch // SQLite provider can continue without being able to find built-in functions

        SQLiteFunctionAttribute at = new SQLiteFunctionAttribute(
            name, argumentCount, functionType);

        at.InstanceType = instanceType;
        at.Callback1 = callback1;
        at.Callback2 = callback2;

        ReplaceFunction(at, null);
    }

    /// <summary>
    /// Replaces a registered function, disposing of the associated (old)
    /// value if necessary.
    /// </summary>
    /// <param name="at">
    /// The attribute that describes the function to replace.
    /// </param>
    /// <param name="newValue">
    /// The new value to use.
    /// </param>
    /// <returns>
    /// Non-zero if an existing registered function was replaced; otherwise,
    /// zero.
    /// </returns>
    private static bool ReplaceFunction(
        SQLiteFunctionAttribute at,
        object newValue
        )
    {
        object oldValue;

        if (_registeredFunctions.TryGetValue(at, out oldValue))
        {
            IDisposable disposable = oldValue as IDisposable;

            if (disposable != null)
            {
                disposable.Dispose();
                disposable = null;
            }

            _registeredFunctions[at] = newValue;
            return true;
        }
        else
        {
            _registeredFunctions.Add(at, newValue);
            return false;
        }
    }

    /// <summary>
    /// Creates a <see cref="SQLiteFunction" /> instance based on the specified
    /// <see cref="SQLiteFunctionAttribute" />.
    /// </summary>
    /// <param name="functionAttribute">

###############################################################################
#
# tkt-2556655d1b.eagle --
#
# Written by Joe Mistachkin.
# Released to the public domain, use at your own risk!
#
###############################################################################

package require Eagle
package require Eagle.Library
package require Eagle.Test

runTestPrologue

###############################################################################

package require System.Data.SQLite.Test
runSQLiteTestPrologue

###############################################################################

###############################################################################

runTest {test tkt-2556655d1b-1.1 {duplicate functions} -setup {
  set fileName tkt-2556655d1b-1.1.db
} -body {
  set id [object invoke Interpreter.GetActive NextId]

  unset -nocomplain results errors

  set code [compileCSharpWith [subst {
    using System;
    using System.Data.SQLite;

    namespace _Dynamic${id}
    {
      \[SQLiteFunction(Name = "Base64", FuncType = FunctionType.Scalar)\]
      public class Test${id} : SQLiteFunction
      {
        public override object Invoke(
          object\[\] args
          )
        {
          if (args == null)
            return null;

          if (args.Length != 1)
            return new ArgumentException(String.Format(
              "need exactly one argument, got {0}", args.Length));

          object arg = args\[0\];

          if (arg == null)
            return String.Empty;

          Type type = arg.GetType();

          if (type == typeof(DBNull))
            return String.Empty;

          if (type != typeof(byte\[\]))
            return new ArgumentException(String.Format(
              "argument must be byte array, got {0}", type));

          return Convert.ToBase64String((byte\[\]) arg);
        }

        ///////////////////////////////////////////////////////////////////////

        public static void Main()
        {
          SQLiteFunction.RegisterFunction(typeof(Test${id}));
          SQLiteFunction.RegisterFunction(typeof(Test${id}));
        }
      }
    }
  }] true true true results errors System.Data.SQLite.dll]

  #
  # NOTE: Compile the C# code (above) to register the custom SQLite function
  #       and then open the database for this test case and attempt to execute
  #       the function.  Normally, we would open the database in the test setup
  #       phase; however, that will not work correctly because newly registered
  #       functions are only picked up and used by databases opened after they
  #       have been registered.
  #
  list $code $results \
      [expr {[info exists errors] ? $errors : ""}] \
      [expr {$code eq "Ok" ? [catch {
        object invoke _Dynamic${id}.Test${id} Main
      } result] : [set result ""]}] $result [setupDb $fileName] \
      [sql execute -execute scalar $db "SELECT Base64(CAST(NULL AS BLOB));"] \
      [sql execute -execute scalar $db "SELECT Base64(CAST('' AS BLOB));"] \
      [sql execute -execute scalar $db "SELECT Base64(CAST('foo' AS BLOB));"]
} -cleanup {
  cleanupDb $fileName

  unset -nocomplain result code results errors id db fileName
} -constraints {eagle command.object monoBug28 command.sql compile.DATA SQLite\
System.Data.SQLite compileCSharp} -match regexp -result {^Ok\
System#CodeDom#Compiler#CompilerResults#\d+ \{\} 0 \{\}\
System#Data#SQLite#SQLiteConnection#\d+ \{\} \{\} Zm9v$}}

###############################################################################

runSQLiteTestEpilogue
runTestEpilogue