initial commit

src/libraries/Microsoft.PowerFx.Core/Functions/UserDefinedFunction.cs

@@ -3,6 +3,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Data;
 using System.Linq;
 using Microsoft.CodeAnalysis;
 using Microsoft.PowerFx.Core.App;
@@ -11,6 +12,7 @@
 using Microsoft.PowerFx.Core.Binding.BindInfo;
 using Microsoft.PowerFx.Core.Entities;
 using Microsoft.PowerFx.Core.Errors;
+using Microsoft.PowerFx.Core.Functions.FunctionArgValidators;
 using Microsoft.PowerFx.Core.Glue;
 using Microsoft.PowerFx.Core.IR;
 using Microsoft.PowerFx.Core.IR.Nodes;
@@ -23,6 +25,7 @@
 using Microsoft.PowerFx.Syntax;
 using Microsoft.PowerFx.Types;
 using static Microsoft.PowerFx.Core.Localization.TexlStrings;
+using CallNode = Microsoft.PowerFx.Syntax.CallNode;
 
 namespace Microsoft.PowerFx.Core.Functions
 {
@@ -31,18 +34,29 @@ namespace Microsoft.PowerFx.Core.Functions
  /// This includings the binding (and hence IR for evaluation) - 
  /// This is conceptually immutable after initialization - if the body or signature changes, you need to create a new instance.
  /// </summary>
- internal class UserDefinedFunction : TexlFunction
+ internal class UserDefinedFunction : TexlFunction, IExternalPageableSymbol, IExternalDelegatableSymbol
  {
  private readonly bool _isImperative;
  private readonly IEnumerable<UDFArg> _args;
  private TexlBinding _binding;
 
  public override bool IsAsync => _binding?.IsAsync(UdfBody) ?? false;
 
+ public bool IsPageable => _binding?.IsPageable(_binding.Top) ?? false;
+
+ public bool IsDelegatable => _binding?.IsDelegatable(_binding.Top) ?? false;
+
+ public override bool IsServerDelegatable(CallNode callNode, TexlBinding binding)
+ {
+ return base.IsServerDelegatable(callNode, binding) || IsDelegatable;
+ }
+
  public override bool SupportsParamCoercion => true;
 
  public TexlNode UdfBody { get; }
 
+ public TexlBinding Binding => _binding;
+
  public override bool IsSelfContained => !_isImperative;
 
  /// <summary>
@@ -142,7 +156,7 @@ public void CheckTypesOnDeclaration(CheckTypesContext context, DType actualBodyR
  }
  else
  {
- binding.ErrorContainer.EnsureError(DocumentErrorSeverity.Severe, UdfBody, TexlStrings.ErrUDF_ReturnTypeDoesNotMatch, ReturnType.GetKindString(), actualBodyReturnType.GetKindString());
+ binding.ErrorContainer.EnsureError(DocumentErrorSeverity.Severe, UdfBody, TexlStrings.ErrUDF_ReturnTypeDoesNotMatch);
  }
  }
  }
@@ -292,27 +306,25 @@ private static bool CheckReturnType(IdentToken returnTypeToken, List<TexlError>
  errors.Add(new TexlError(returnTypeToken, DocumentErrorSeverity.Severe, TexlStrings.ErrUDF_UnknownType, returnTypeToken.Name));
  returnType = DType.Invalid;
  return false;
- }
- 
+ }
+
  if (IsRestrictedType(returnTypeFormulaType))
  {
  errors.Add(new TexlError(returnTypeToken, DocumentErrorSeverity.Severe, TexlStrings.ErrUDF_InvalidReturnType, returnTypeToken.Name));
  returnType = DType.Invalid;
  return false;
- }
- 
+ }
+
  returnType = returnTypeFormulaType._type;
- return true; 
+ return true;
  }
 
  // To prevent aggregate types from containing restricted types
  internal static bool IsRestrictedType(FormulaType ft)
  {
  Contracts.AssertValue(ft);
 
- // Datasource types may contain fields that may expand to other datasource types or refernce themselves.
- // We can avoid calling this method on these types containing expand info.
- if (!ft._type.HasExpandInfo && ft is AggregateType aggType)
+ if (ft is AggregateType aggType)
  {
  if (aggType.GetFieldTypes().Any(ct => IsRestrictedType(ct.Type)))
  {
@@ -391,8 +403,8 @@ public bool LookupDataControl(DName name, out NameLookupInfo lookupInfo, out DNa
  }
 
  public IEnumerable<TexlFunction> LookupFunctions(DPath theNamespace, string name, bool localeInvariant = false)
- {
- return _globalNameResolver.LookupFunctions(theNamespace, name, localeInvariant);
+ {
+  return _globalNameResolver.LookupFunctions(theNamespace, name, localeInvariant);
  }
 
  public IEnumerable<TexlFunction> LookupFunctionsInNamespace(DPath nameSpace)