Equality operators now work for non-constants as well

Author: nothrow

src/System.Linq.Dynamic.Core/Parser/ExpressionParser.cs

@@ -1920,10 +1920,10 @@ void CheckAndPromoteOperands(Type signatures, TokenId opId, string opName, ref E
 
             if (nativeOperation != null)
             {
-                if (left is ConstantExpression)
+                // first try left operand's equality operators
+                found = _methodFinder.ContainsMethod(left.Type, nativeOperation, true, args);
+                if (!found)
                     found = _methodFinder.ContainsMethod(right.Type, nativeOperation, true, args);
-                else if (right is ConstantExpression)
-                    found = _methodFinder.ContainsMethod(left.Type, nativeOperation, true, args);
             }
 
             if (!found && !_methodFinder.ContainsMethod(signatures, "F", false, args))

src/System.Linq.Dynamic.Core/System.Linq.Dynamic.Core.csproj

@@ -3,7 +3,7 @@
         <Description>This is a .NETStandard / .NET Core port of the the Microsoft assembly for the .Net 4.0 Dynamic language functionality.</Description>
         <AssemblyTitle>System.Linq.Dynamic.Core</AssemblyTitle>
         <Authors>Microsoft;Scott Guthrie;King Wilder;Nathan Arnott;Stef Heyenrath</Authors>
-        <TargetFrameworks>net35;net40;net45;net46;netstandard1.3;netstandard2.0;uap10.0;netcoreapp2.1</TargetFrameworks>
+        <TargetFrameworks>net35;net40;net45;net46;netstandard1.3;netstandard2.0;netcoreapp2.1</TargetFrameworks>
         <GenerateDocumentationFile>true</GenerateDocumentationFile>
         <AssemblyName>System.Linq.Dynamic.Core</AssemblyName>
         <AssemblyOriginatorKeyFile>System.Linq.Dynamic.Core.snk</AssemblyOriginatorKeyFile>

test/System.Linq.Dynamic.Core.Tests/ExpressionTests.cs

@@ -1715,6 +1715,43 @@ public void ExpressionTests_Type_StructWithIntegerEquality()
             Assert.Equal(resultValuesL.ToArray(), resultIn);
         }
 
+        [Fact]
+        public void ExpressionTests_Type_StructWithIntegerEquality_BothVariablesInStruct()
+        {
+            // Arrange
+            var valuesL = new[]
+            {
+                new
+                {
+                    Id = new SnowflakeId(1L), 
+                    Var = 1
+                },
+                new
+                {
+                    Id = new SnowflakeId(2L), 
+                    Var = 1
+                },
+                new
+                {
+                    Id = new SnowflakeId(1L), 
+                    Var = 2
+                }
+            }.AsQueryable();
+
+            var resultValuesL = new[] { 
+                new {
+                    Id = new SnowflakeId(1L), 
+                    Var = 1
+                }
+            }.AsQueryable();
+
+            // Act
+            var resultL = valuesL.Where("it.Id == it.Var");
+
+            // Assert
+            Assert.Equal(resultValuesL.ToArray(), resultL);
+        }
+
         [Fact]
         public void ExpressionTests_Type_Integer_Qualifiers_Negative()
         {