Fix issue with ToLowerInvariant() method in LiteDBRepository.cs Setup…

… failed: Method ToLowerInvariant() in String are not supported when convert to BsonExpression #479

src/Core/Grand.Data/LiteDb/LiteDBRepository.cs

@@ -100,7 +100,10 @@ public virtual async Task<T> GetByIdAsync(string id)
         /// <returns>Entity</returns>
         public virtual Task<T> GetOneAsync(Expression<Func<T, bool>> predicate)
         {
-            return Task.FromResult(_collection.Find(predicate).FirstOrDefault());
+            var visitor = new ToLowerInvariantVisitor();
+            //WORKAROUND Issue #479 - Method ToLowerInvariant() in String are not supported when convert to BsonExpression
+            var modifiedExpression = (Expression<Func<T, bool>>)visitor.Visit(predicate);
+            return Task.FromResult(_collection.Find(modifiedExpression).FirstOrDefault());
         }
 
         /// <summary>

src/Core/Grand.Data/LiteDb/ToLowerInvariantVisitor.cs

@@ -0,0 +1,19 @@
+using System.Linq.Expressions;
+
+namespace Grand.Data.LiteDb;
+public class ToLowerInvariantVisitor : ExpressionVisitor
+{
+    protected override Expression VisitMethodCall(MethodCallExpression node)
+    {
+        if (node.Method == typeof(string).GetMethod("ToLowerInvariant", Type.EmptyTypes))
+        {
+            var invariantMethod = typeof(string).GetMethod("ToLower", Type.EmptyTypes);
+            if (invariantMethod != null)
+            {
+                return Expression.Call(node.Object, invariantMethod);
+            }
+
+        }
+        return base.VisitMethodCall(node);
+    }
+}

src/Tests/Grand.Data.Tests/LiteDb/LiteDbRepositoryTests.cs

@@ -66,7 +66,7 @@ public async Task GetByIdAsync_LiteRepository_Success()
         }
 
         [TestMethod()]
-        public async Task GetOneAsyncAsync_LiteRepository_Success()
+        public async Task GetOneAsync_LiteRepository_Success()
         {
             var myRepository = new LiteDBRepositoryMock<SampleCollection>();
             var product = new SampleCollection { Id = "1" };
@@ -76,7 +76,17 @@ public async Task GetOneAsyncAsync_LiteRepository_Success()
 
             Assert.IsNotNull(p);
         }
+        [TestMethod()]
+        public async Task GetOneAsync_ToLowerInvariant_LiteRepository_Success()
+        {
+            var myRepository = new LiteDBRepositoryMock<SampleCollection>();
+            var product = new SampleCollection { Id = "1" };
+            await myRepository.InsertAsync(product);
+
+            var p = await myRepository.GetOneAsync(x => x.Id == "1".ToLowerInvariant());
 
+            Assert.IsNotNull(p);
+        }
         [TestMethod()]
         public async Task ClearAsync_LiteRepository_Success()
         {