//public override SqlExpression VisitConstant(SqlConstantExpression constant) {
// var value = constant.Value;
// if (value.IsNull)
// return constant;
// var obj = value.Value;
// if (obj is SqlQueryObject) {
// return EvaluateQueryPlan((SqlQueryObject) obj);
// }
// return base.VisitConstant(constant);
//}
//private SqlConstantExpression EvaluateQueryPlan(SqlQueryObject obj) {
// if (context.QueryContext == null)
// throw new ExpressionEvaluateException("A query context is required to evaluate a query.");
// try {
// var plan = obj.QueryPlan;
// var result = plan.Evaluate(context.QueryContext);
// return SqlExpression.Constant(new DataObject(new TabularType(), SqlTabular.From(result)));
// } catch (ExpressionEvaluateException) {
// throw;
// } catch (Exception ex) {
// throw new ExpressionEvaluateException("Could not evaluate a query.", ex);
// }
//}
public override SqlExpression VisitFunctionCall(SqlFunctionCallExpression expression)
{
try {
var invoke = new Invoke(expression.FunctioName, expression.Arguments);
IRequest request = null;
IVariableResolver variableResolver = null;
IGroupResolver groupResolver = null;
if (context != null)
{
request = context.Request;
variableResolver = context.VariableResolver;
groupResolver = context.GroupResolver;
}
// TODO: if we don't have a return value (PROCEDURES) what should w return?
var result = invoke.Execute(request, variableResolver, groupResolver);
if (!result.HasReturnValue)
{
return(SqlExpression.Constant(DataObject.Null()));
}
return(SqlExpression.Constant(result.ReturnValue));
} catch (ExpressionEvaluateException) {
throw;
} catch (Exception ex) {
throw new ExpressionEvaluateException(String.Format("Could not evaluate function expression '{0}' because of an error.", expression), ex);
}
}
public void ShouldInvokeMethods()
{
var @case = Case("Returns");
invoke.Execute(@case, this);
invoked.ShouldBeTrue();
@case.Exceptions.Count.ShouldEqual(0);
}
public InvokeResult Execute(InvokeContext context)
{
// Rewrite the function to the object initialization
var sourceArgs = context.Arguments == null ? new InvokeArgument[1] : context.Arguments;
var args = new InvokeArgument[sourceArgs.Length + 1];
Array.Copy(sourceArgs, 0, args, 1, sourceArgs.Length);
args[0] = new InvokeArgument(SqlExpression.Constant(FunctionInfo.RoutineName.FullName));
var initFunction = context.Request.Access().ResolveObjectName(DbObjectType.Routine, ObjectName.Parse("SYSTEM.NEW_OBJECT"));
if (initFunction == null)
{
throw new InvalidOperationException("The object initialization function was not defined.");
}
var invoke = new Invoke(initFunction, args);
return(invoke.Execute(context.Request, context.VariableResolver, context.GroupResolver));
}
public Field InvokeFunction(IRequest request, Invoke invoke)
{
var result = invoke.Execute(request);
return(result.ReturnValue);
}
static void Main(string[] args)
{
Invoke.Execute();
}
