add in #1928 removed NullValueRetriever back (#2067)

TechTalk.SpecFlow/Assist/ValueRetrievers/NullValueRetriever.cs

@@ -0,0 +1,33 @@
+using System;
+using System.Collections.Generic;
+
+namespace TechTalk.SpecFlow.Assist.ValueRetrievers
+{
+    public class NullValueRetriever : IValueRetriever
+    {
+        private readonly string _nullText;
+
+        public NullValueRetriever(string nullText)
+        {
+            _nullText = nullText;
+        }
+
+        public bool CanRetrieve(KeyValuePair<string, string> keyValuePair, Type targetType, Type propertyType)
+        {
+            return IsNullableType(propertyType) &&
+                   keyValuePair.Value != null &&
+                   string.Compare(keyValuePair.Value.Trim(), _nullText, StringComparison.InvariantCultureIgnoreCase) == 0;
+        }
+
+        public object Retrieve(KeyValuePair<string, string> keyValuePair, Type targetType, Type propertyType)
+        {
+            return null;
+        }
+
+        private static bool IsNullableType(Type type)
+        {
+            return !type.IsValueType || 
+                (type.IsGenericType && type.GetGenericTypeDefinition() == typeof(Nullable<>));
+        }
+    }
+}

Tests/TechTalk.SpecFlow.RuntimeTests/AssistTests/ValueRetrieverTests/NullValueRetrieverTests.cs

@@ -0,0 +1,105 @@
+using System;
+using FluentAssertions;
+using TechTalk.SpecFlow.Assist.ValueRetrievers;
+using Xunit;
+
+namespace TechTalk.SpecFlow.RuntimeTests.AssistTests.ValueRetrieverTests
+{
+    public class NullValueRetrieverTests
+    {
+        private const string TestNullValue = "MyNullValue";
+
+        [Theory]
+        [InlineData("MyNullValue")]
+        [InlineData(" \tMyNullValue\t ")]
+        [InlineData("MyNuLLValue")]
+        [InlineData("\tMyNuLLValue\t")]
+        public void Can_retrieve_null_value(string value)
+        {
+            var retriever = CreateTestee();
+
+            var actual = retriever.CanRetrieve<object>(value);
+
+            actual.Should().BeTrue();
+        }
+
+        [Theory]
+        [InlineData(typeof(object))]
+        [InlineData(typeof(bool?))]
+        public void Can_retrieve_nullable_types(Type propertyType)
+        {
+            var retriever = CreateTestee();
+
+            var actual = retriever.CanRetrieve(TestNullValue, propertyType);
+
+            actual.Should().BeTrue();
+        }
+
+        [Theory]
+        [InlineData(null)]
+        [InlineData("")]
+        [InlineData("Any string")]
+        [InlineData("30.0")]
+        [InlineData("true")]
+        [InlineData(" \t ")]
+        public void Cannot_retrieve_non_null_values(string value)
+        {
+            var retriever = CreateTestee();
+
+            var actual = retriever.CanRetrieve<object>(value);
+
+            actual.Should().BeFalse();
+        }
+
+        [Theory]
+        [InlineData(typeof(bool))]
+        [InlineData(typeof(Guid))]
+        [InlineData(typeof(StringSplitOptions))]
+        public void Cannot_retrieve_non_nullable_types(Type propertyType)
+        {
+            var retriever = CreateTestee();
+
+            var actual = retriever.CanRetrieve(TestNullValue, propertyType);
+
+            actual.Should().BeFalse();
+        }
+
+        [Theory]
+        [InlineData(null)]
+        [InlineData("")]
+        [InlineData("Any string")]
+        [InlineData("30.0")]
+        [InlineData("true")]
+        [InlineData(" \t ")]
+        [InlineData(" \tMyNullValue\t ")]
+        [InlineData("MyNuLLValue")]
+        public void Retrieves_null_for_any_value(string value)
+        {
+            var retriever = CreateTestee();
+
+            var actual = retriever.GetValue<object>(value);
+
+            actual.Should().BeNull();
+        }
+
+        [Theory]
+        [InlineData(typeof(object))]
+        [InlineData(typeof(bool?))]
+        [InlineData(typeof(bool))]
+        [InlineData(typeof(Guid))]
+        [InlineData(typeof(StringSplitOptions))]
+        public void Retrieves_null_for_any_type(Type propertyType)
+        {
+            var retriever = CreateTestee();
+
+            var actual = retriever.GetValue("Any value", propertyType);
+
+            actual.Should().BeNull();
+        }
+
+        private NullValueRetriever CreateTestee()
+        {
+            return new NullValueRetriever(TestNullValue);
+        }
+    }
+}

Tests/TechTalk.SpecFlow.RuntimeTests/AssistTests/ValueRetrieverTests/ValueRetrieverTestsUtils.cs

@@ -0,0 +1,29 @@
+using System;
+using System.Collections.Generic;
+using TechTalk.SpecFlow.Assist;
+
+namespace TechTalk.SpecFlow.RuntimeTests.AssistTests.ValueRetrieverTests
+{
+    internal static class ValueRetrieverTestsUtils
+    {
+        internal static bool CanRetrieve<TProperty>(this IValueRetriever retriever, string value)
+        {
+            return retriever.CanRetrieve(value, typeof(TProperty));
+        }
+
+        internal static bool CanRetrieve(this IValueRetriever retriever, string value, Type propertyType)
+        {
+            return retriever.CanRetrieve(new KeyValuePair<string, string>("Value", value), typeof(object), propertyType);
+        }
+
+        internal static TProperty GetValue<TProperty>(this IValueRetriever retriever, string value)
+        {
+            return (TProperty)retriever.GetValue(value, typeof(TProperty));
+        }
+
+        internal static object GetValue(this IValueRetriever retriever, string value, Type propertyType)
+        {
+            return retriever.Retrieve(new KeyValuePair<string, string>("Value", value), typeof(object), propertyType);
+        }
+    }
+}

changelog.txt

@@ -4,6 +4,7 @@ Fixes:
 + Fix step definition attribute support for the Visual Studio Extension #2065
 
 Changes:
++ Add NullValueRetriever back again (was accidential removed with https://github.com/SpecFlowOSS/SpecFlow/pull/1928) - https://github.com/SpecFlowOSS/SpecFlow/pull/2067
 + Add a new `TestRunEnd` extension point for plugins
 
 3.3.57