removed implicit null check on object

Author: Jamess-Lucass

example/Controllers/UserController.cs

@@ -1,3 +1,5 @@
+using AutoMapper;
+using AutoMapper.QueryableExtensions;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.EntityFrameworkCore;
 
@@ -6,24 +8,28 @@
 public class UsersController : ControllerBase
 {
     private readonly ApplicationDbContext _db;
-    public UsersController(ApplicationDbContext db)
+    private readonly IMapper _mapper;
+
+    public UsersController(ApplicationDbContext db, IMapper mapper)
     {
         _db = db;
+        _mapper = mapper;
     }
 
     // GET: /controller/users
     [HttpGet]
-    [ProducesResponseType(typeof(IEnumerable<User>), StatusCodes.Status200OK)]
-    [EnableQuery<User>(maxTop: 10)]
-    public ActionResult<IEnumerable<User>> Get()
+    [ProducesResponseType(typeof(IEnumerable<UserDto>), StatusCodes.Status200OK)]
+    [EnableQuery<UserDto>(maxTop: 10)]
+    public ActionResult<IEnumerable<UserDto>> Get()
     {
         var users = _db.Users
             .Include(x => x.Company)
             .Include(x => x.Addresses)
                 .ThenInclude(x => x.City)
             .Include(x => x.Manager)
                 .ThenInclude(x => x.Manager)
-            .Where(x => !x.IsDeleted);
+            .Where(x => !x.IsDeleted)
+            .ProjectTo<UserDto>(_mapper.ConfigurationProvider);
 
         return Ok(users);
     }

example/Dto/UserDto.cs

@@ -0,0 +1,38 @@
+using System.Text.Json.Serialization;
+
+public record UserDto
+{
+    public Guid Id { get; set; }
+
+    [JsonPropertyName("first_name")]
+    public string Firstname { get; set; } = string.Empty;
+    public string Lastname { get; set; } = string.Empty;
+    public int Age { get; set; }
+    public bool IsEmailVerified { get; set; }
+    public double Test { get; set; }
+    public int? NullableInt { get; set; }
+    public DateTime DateOfBirthUtc { get; set; }
+    public DateTime DateOfBirthTz { get; set; }
+    public User? Manager { get; set; }
+    public IEnumerable<AddressDto> Addresses { get; set; } = Array.Empty<AddressDto>();
+    public IEnumerable<string> Tags { get; set; } = Array.Empty<string>();
+    public CompanyDto? Company { get; set; }
+}
+
+public record AddressDto
+{
+    public string AddressLine1 { get; set; } = string.Empty;
+    public CityDto City { get; set; } = new CityDto();
+}
+
+public record CityDto
+{
+    public string Name { get; set; } = string.Empty;
+    public string Country { get; set; } = string.Empty;
+}
+
+public record CompanyDto
+{
+    public string Name { get; set; } = string.Empty;
+    public string Department { get; set; } = string.Empty;
+}

example/Profiles/AutoMapperProfile.cs

@@ -0,0 +1,12 @@
+using AutoMapper;
+
+public class AutoMapperProfile : Profile
+{
+    public AutoMapperProfile()
+    {
+        CreateMap<User, UserDto>();
+        CreateMap<Address, AddressDto>();
+        CreateMap<City, CityDto>();
+        CreateMap<Company, CompanyDto>();
+    }
+}

example/Program.cs

@@ -1,4 +1,8 @@
+using System.Reflection;
+using AutoMapper;
+using AutoMapper.QueryableExtensions;
 using Bogus;
+using Microsoft.AspNetCore.Mvc;
 using Microsoft.EntityFrameworkCore;
 using Testcontainers.PostgreSql;
 
@@ -19,6 +23,8 @@
     options.UseNpgsql(postgreSqlContainer.GetConnectionString());
 });
 
+builder.Services.AddAutoMapper(Assembly.GetExecutingAssembly());
+
 var app = builder.Build();
 
 using (var scope = app.Services.CreateScope())
@@ -71,7 +77,7 @@
 
 Console.WriteLine($"Postgres connection string: {postgreSqlContainer.GetConnectionString()}");
 
-app.MapGet("/minimal/users", (ApplicationDbContext db, [AsParameters] Query query) =>
+app.MapGet("/minimal/users", (ApplicationDbContext db, [FromServices] IMapper mapper, [AsParameters] Query query) =>
 {
     var result = db.Users
         .Include(x => x.Company)
@@ -80,14 +86,15 @@
             .Include(x => x.Manager)
                 .ThenInclude(x => x.Manager)
             .Where(x => !x.IsDeleted)
+        .ProjectTo<UserDto>(mapper.ConfigurationProvider)
         .Apply(query);
 
     if (result.IsFailed)
     {
         return Results.BadRequest(new { message = result.Errors });
     }
 
-    var response = new PagedResponse<User>(result.Value.Query.ToList(), result.Value.Count);
+    var response = new PagedResponse<UserDto>(result.Value.Query.ToList(), result.Value.Count);
 
     return Results.Ok(response);
 });

example/example.csproj

@@ -7,6 +7,7 @@
   </PropertyGroup>
 
   <ItemGroup>
+    <PackageReference Include="AutoMapper.Extensions.Microsoft.DependencyInjection" Version="12.0.1" />
     <PackageReference Include="Bogus" Version="35.6.3" />
     <PackageReference Include="Npgsql.EntityFrameworkCore.PostgreSQL" Version="9.0.4" />
     <PackageReference Include="Testcontainers" Version="4.5.0" />

src/GoatQuery/src/Evaluator/FilterEvaluator.cs

@@ -55,27 +55,26 @@ private static Result<Expression> EvaluatePropertyPathExpression(
         var propertyPathResult = BuildPropertyPath(propertyPath, baseExpression, context.PropertyMappingTree);
         if (propertyPathResult.IsFailed) return Result.Fail(propertyPathResult.Errors);
 
-        var (finalProperty, nullChecks) = propertyPathResult.Value;
+        var finalProperty = propertyPathResult.Value;
 
         if (exp.Right is NullLiteral)
         {
             var nullComparison = CreateNullComparison(exp, finalProperty);
-            return CombineWithNullChecks(nullComparison, nullChecks);
+            return nullComparison;
         }
 
         var comparisonResult = EvaluateValueComparison(exp, finalProperty);
         if (comparisonResult.IsFailed) return comparisonResult;
 
-        return CombineWithNullChecks(comparisonResult.Value, nullChecks);
+        return comparisonResult.Value;
     }
 
-    private static Result<(MemberExpression Property, List<Expression> NullChecks)> BuildPropertyPath(
+    private static Result<MemberExpression> BuildPropertyPath(
         PropertyPath propertyPath,
         Expression startExpression,
         PropertyMappingTree propertyMappingTree)
     {
         var current = startExpression;
-        var nullChecks = new List<Expression>();
         var currentMappingTree = propertyMappingTree;
 
         foreach (var (segment, isLast) in propertyPath.Segments.Select((s, i) => (s, i == propertyPath.Segments.Count - 1)))
@@ -85,12 +84,6 @@ private static Result<Expression> EvaluatePropertyPathExpression(
 
             current = Expression.Property(current, propertyNode.ActualPropertyName);
 
-            // Add null check for intermediate reference types only (not the final property)
-            if (!isLast && IsNullableReferenceType(current.Type))
-            {
-                nullChecks.Add(Expression.NotEqual(current, Expression.Constant(null, current.Type)));
-            }
-
             // Navigate to nested mapping for next segment
             if (!isLast)
             {
@@ -101,7 +94,7 @@ private static Result<Expression> EvaluatePropertyPathExpression(
             }
         }
 
-        return Result.Ok(((MemberExpression)current, nullChecks));
+        return Result.Ok((MemberExpression)current);
     }
 
     private static Result<MemberExpression> ResolvePropertyPathForCollection(
@@ -185,17 +178,6 @@ private static Expression CreateDateComparison(Expression dateProperty, Constant
         };
     }
 
-    private static Result<Expression> CombineWithNullChecks(Expression comparison, List<Expression> nullChecks)
-    {
-        if (!nullChecks.Any())
-        {
-            return comparison;
-        }
-
-        var allNullChecks = nullChecks.Aggregate(Expression.AndAlso);
-
-        return Expression.AndAlso(allNullChecks, comparison);
-    }
 
     private static Result<Expression> EvaluateValueComparison(InfixExpression exp, MemberExpression property)
     {