Update capabilities to support different Join types (#2805)

This is to support datasources that don't necessarily support all Join
types like DV which doesn't support right joins

Author: LucGenetier

src/libraries/Microsoft.PowerFx.Core/Functions/Delegation/DelegationCapability.cs

@@ -88,7 +88,10 @@ internal struct DelegationCapability
                 { DelegationMetadataOperatorConstants.AsType, new DelegationCapability(AsType) },
                 { DelegationMetadataOperatorConstants.ArrayLookup, new DelegationCapability(ArrayLookup) },
                 { DelegationMetadataOperatorConstants.Distinct, new DelegationCapability(Distinct) },
-                { DelegationMetadataOperatorConstants.Join, new DelegationCapability(Join) }
+                { DelegationMetadataOperatorConstants.JoinInner, new DelegationCapability(JoinInner) },
+                { DelegationMetadataOperatorConstants.JoinLeft, new DelegationCapability(JoinLeft) },
+                { DelegationMetadataOperatorConstants.JoinRight, new DelegationCapability(JoinRight) },
+                { DelegationMetadataOperatorConstants.JoinFull, new DelegationCapability(JoinFull) }
             }, isThreadSafe: true);
 
         // Supported delegatable operations.
@@ -140,10 +143,13 @@ internal struct DelegationCapability
         public static readonly BigInteger AsType = BigInteger.Pow(2, 44);                       //    0x100000000000
         public static readonly BigInteger ArrayLookup = BigInteger.Pow(2, 45);                  //    0x200000000000
         public static readonly BigInteger Distinct = BigInteger.Pow(2, 46);                     //    0x400000000000
-        public static readonly BigInteger Join = BigInteger.Pow(2, 47);                         //    0x800000000000
+        public static readonly BigInteger JoinInner = BigInteger.Pow(2, 47);                    //    0x800000000000
+        public static readonly BigInteger JoinLeft = BigInteger.Pow(2, 48);                     //   0x1000000000000
+        public static readonly BigInteger JoinRight = BigInteger.Pow(2, 49);                    //   0x2000000000000
+        public static readonly BigInteger JoinFull = BigInteger.Pow(2, 50);                     //   0x4000000000000
 
         // Please update it as max value changes.
-        private static BigInteger maxSingleCapabilityValue = Join;
+        private static BigInteger maxSingleCapabilityValue = JoinFull;
 
         // Indicates support all functionality.
         public static BigInteger SupportsAll
@@ -481,10 +487,28 @@ internal string DebugString
                     sb.Append(nameof(Distinct));
                 }
 
-                if (HasCapability(Join))
+                if (HasCapability(JoinInner))
                 {
                     AddCommaIfNeeded(sb);
-                    sb.Append(nameof(Join));
+                    sb.Append(nameof(JoinInner));
+                }
+
+                if (HasCapability(JoinLeft))
+                {
+                    AddCommaIfNeeded(sb);
+                    sb.Append(nameof(JoinLeft));
+                }
+
+                if (HasCapability(JoinRight))
+                {
+                    AddCommaIfNeeded(sb);
+                    sb.Append(nameof(JoinRight));
+                }
+
+                if (HasCapability(JoinFull))
+                {
+                    AddCommaIfNeeded(sb);
+                    sb.Append(nameof(JoinFull));
                 }
 
                 return sb.ToString();

src/libraries/Microsoft.PowerFx.Core/Functions/Delegation/DelegationMetadataOperatorConstants.cs

@@ -52,7 +52,10 @@ internal static class DelegationMetadataOperatorConstants
         public const string AsType = "astype";
         public const string ArrayLookup = "arraylookup";
         public const string Distinct = "distinct";
-        public const string Join = "join";
+        public const string JoinInner = "joininner";
+        public const string JoinLeft = "joinleft";
+        public const string JoinRight = "joinright";
+        public const string JoinFull = "joinfull";
     }
 
     public enum DelegationOperator
@@ -98,6 +101,9 @@ public enum DelegationOperator
         Astype,
         Arraylookup,
         Distinct,
-        Join
+        JoinInner,
+        JoinLeft,
+        JoinRight,
+        JoinFull
     }
 }