Fix String.Equals together with other condition (#800)

Author: StefH

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

@@ -2065,17 +2065,17 @@ private bool TryParseEnumerable(Expression instance, Type elementType, string me
 
         args = ParseArgumentList();
 
-        var t = type ?? instance.Type;
-        if (t == typeof(string) && _methodFinder.ContainsMethod(t, methodName, false, instance, ref args))
+        _it = outerIt;
+        _parent = oldParent;
+
+        var typeToCheckForTypeOfString = type ?? instance.Type;
+        if (typeToCheckForTypeOfString == typeof(string) && _methodFinder.ContainsMethod(typeToCheckForTypeOfString, methodName, false, instance, ref args))
         {
             // In case the type is a string, and does contain the methodName (like "IndexOf"), then return false to indicate that the methodName is not an Enumerable method.
             expression = null;
             return false;
         }
-
-        _it = outerIt;
-        _parent = oldParent;
-
+        
         if (type != null && TypeHelper.IsDictionary(type) && _methodFinder.ContainsMethod(type, methodName, false))
         {
             var dictionaryMethod = type.GetMethod(methodName)!;

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

@@ -1595,7 +1595,7 @@ public void DynamicExpressionParser_ParseLambda_RenameEmptyParameterExpressionNa
     [Theory]
     [InlineData(@"p0.Equals(""Testing"", 3)", "testinG", true)]
     [InlineData(@"p0.Equals(""Testing"", StringComparison.InvariantCultureIgnoreCase)", "testinG", true)]
-    public void DynamicExpressionParser_ParseLambda_SupportEnumerationStringComparison(string expressionAsString, string testValue, bool expectedResult)
+    public void DynamicExpressionParser_ParseLambda_StringEquals(string expressionAsString, string testValue, bool expectedResult)
     {
         // Arrange
         var p0 = Expression.Parameter(typeof(string), "p0");
@@ -1609,6 +1609,26 @@ public void DynamicExpressionParser_ParseLambda_SupportEnumerationStringComparis
         Check.That(result).IsEqualTo(expectedResult);
     }
 
+    // #799
+    [Theory]
+    [InlineData(@"UserName.Equals(""Testing"", 3) and Income > 0")]
+    [InlineData(@"UserName.Equals(""Testing"", StringComparison.InvariantCultureIgnoreCase) and Income > 0")]
+    [InlineData(@"Income > 0 && UserName.Equals(""Testing"", 3)")]
+    [InlineData(@"Income > 0 && UserName.Equals(""Testing"", StringComparison.InvariantCultureIgnoreCase)")]
+    public void DynamicExpressionParser_ParseLambda_StringEquals_WithCombinedCondition(string expressionAsString)
+    {
+        // Arrange
+        var u = Expression.Parameter(typeof(User), "u");
+
+        // Act
+        var expression = DynamicExpressionParser.ParseLambda(new[] { u }, typeof(bool), expressionAsString);
+        var del = expression.Compile();
+        var result = del.DynamicInvoke(new User { UserName = "testinG", Income = 10 }) as bool?;
+
+        // Assert
+        Check.That(result).IsEqualTo(true);
+    }
+
     [Fact]
     public void DynamicExpressionParser_ParseLambda_NullPropagation_InstanceMethod_0_Arguments()
     {

test/System.Linq.Dynamic.Core.Tests/QueryableTests.Is,OfType,As,Cast.cs

@@ -508,10 +508,12 @@ public void CastToIntUsingParentheses()
             }.AsQueryable();
 
             // Act
-            var result = qry.Where("DisplayName.Any(int(it) >= 109)").ToDynamicArray<User>();
+            var result1 = qry.Where("DisplayName.Any(int(it) >= 109) and Id > 0").ToDynamicArray<User>();
+            var result2 = qry.Where("Id > 0 && DisplayName.Any(int(it) >= 109)").ToDynamicArray<User>();
 
             // Assert
-            result.Should().HaveCount(1).And.Subject.First().Id.Should().Be(1);
+            result1.Should().HaveCount(1).And.Subject.First().Id.Should().Be(1);
+            result2.Should().HaveCount(1).And.Subject.First().Id.Should().Be(1);
         }
 
         [Fact]