Adding tests

test/Microsoft.AspNet.Mvc.Core.Test/ModelBinding/GenericModelBinderTest.cs

@@ -0,0 +1,149 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using Microsoft.AspNet.Http.Internal;
+using Microsoft.AspNet.Mvc.ModelBinding;
+using Xunit;
+
+namespace Microsoft.AspNet.Mvc
+{
+    public class GenericModelBinderTest
+    {
+        [Fact]
+        public async Task GenericModelBinder_DoesNotCreateCollection_ForTopLevelModel_OnFirstPass()
+        {
+            // Arrange
+            var binder = new GenericModelBinder();
+
+            var context = CreateContext();
+            context.ModelName = "param";
+
+            var metadataProvider = context.OperationBindingContext.MetadataProvider;
+            context.ModelMetadata = metadataProvider.GetMetadataForType(typeof(List<string>));
+
+            context.ValueProvider = new TestValueProvider(new Dictionary<string, object>());
+
+            // Act
+            var result = await binder.BindModelAsync(context);
+
+            // Assert
+            Assert.NotNull(result);
+
+            Assert.Null(result.Model);
+            Assert.Equal("param", result.Key);
+            Assert.False(result.IsModelSet);
+            Assert.Null(result.ValidationNode);
+        }
+
+        [Fact]
+        public async Task GenericModelBinder_CreatesEmptyCollection_ForTopLevelModel_OnFallback()
+        {
+            // Arrange
+            var binder = new GenericModelBinder();
+
+            var context = CreateContext();
+            context.ModelName = string.Empty;
+
+            var metadataProvider = context.OperationBindingContext.MetadataProvider;
+            context.ModelMetadata = metadataProvider.GetMetadataForType(typeof(List<string>));
+
+            context.ValueProvider = new TestValueProvider(new Dictionary<string, object>());
+
+            // Act
+            var result = await binder.BindModelAsync(context);
+
+            // Assert
+            Assert.NotNull(result);
+
+            Assert.Empty(Assert.IsType<List<string>>(result.Model));
+            Assert.Equal(string.Empty, result.Key);
+            Assert.True(result.IsModelSet);
+
+            Assert.Same(result.ValidationNode.Model, result.Model);
+            Assert.Same(result.ValidationNode.Key, result.Key);
+            Assert.Same(result.ValidationNode.ModelMetadata, context.ModelMetadata);
+        }
+
+        [Fact]
+        public async Task GenericModelBinder_CreatesEmptyCollection_ForTopLevelModel_WithExplicitPrefix()
+        {
+            // Arrange
+            var binder = new GenericModelBinder();
+
+            var context = CreateContext();
+            context.ModelName = "prefix";
+            context.BinderModelName = "prefix";
+
+            var metadataProvider = context.OperationBindingContext.MetadataProvider;
+            context.ModelMetadata = metadataProvider.GetMetadataForType(typeof(List<string>));
+
+            context.ValueProvider = new TestValueProvider(new Dictionary<string, object>());
+
+            // Act
+            var result = await binder.BindModelAsync(context);
+
+            // Assert
+            Assert.NotNull(result);
+
+            Assert.Empty(Assert.IsType<List<string>>(result.Model));
+            Assert.Equal("prefix", result.Key);
+            Assert.True(result.IsModelSet);
+
+            Assert.Same(result.ValidationNode.Model, result.Model);
+            Assert.Same(result.ValidationNode.Key, result.Key);
+            Assert.Same(result.ValidationNode.ModelMetadata, context.ModelMetadata);
+        }
+
+        [Theory]
+        [InlineData("")]
+        [InlineData("param")]
+        public async Task GenericModelBinder_DoesNotCreateCollection_ForNonTopLevelModel(string prefix)
+        {
+            // Arrange
+            var binder = new GenericModelBinder();
+
+            var context = CreateContext();
+            context.ModelName = ModelNames.CreatePropertyModelName(prefix, "ListProperty");
+
+            var metadataProvider = context.OperationBindingContext.MetadataProvider;
+            context.ModelMetadata = metadataProvider.GetMetadataForProperty(
+                typeof(ModelWithListProperty),
+                nameof(ModelWithListProperty.ListProperty));
+
+            context.ValueProvider = new TestValueProvider(new Dictionary<string, object>());
+
+            // Act
+            var result = await binder.BindModelAsync(context);
+
+            // Assert
+            Assert.NotNull(result);
+
+            Assert.Null(result.Model);
+            Assert.Same(context.ModelName, result.Key);
+            Assert.False(result.IsModelSet);
+            Assert.Null(result.ValidationNode);
+        }
+
+        private class ModelWithListProperty
+        {
+            public List<string> ListProperty { get; set; }
+        }
+
+        private static ModelBindingContext CreateContext()
+        {
+            var modelBindingContext = new ModelBindingContext()
+            {
+                OperationBindingContext = new OperationBindingContext()
+                {
+                    HttpContext = new DefaultHttpContext(),
+                    MetadataProvider = new TestModelMetadataProvider(),
+                }
+            };
+
+            return modelBindingContext;
+        }
+    }
+}