Adding PropertyInfo.IsReadable() and .IsWritable() / Adding MemberInfo.HasAttribute<TAttribute>()

Author: SteveWilkes

NetStandardPolyfills.UnitTests.Net40/WhenRetrievingTypeMembers.cs

@@ -5,6 +5,12 @@ namespace AgileObjects.NetStandardPolyfills.UnitTests.Net40
     [TestFixture]
     public class WhenRetrievingTypeMembers : MemberTestsBase
     {
+        [Test]
+        public override void ShouldFlagAMemberWithAnAttribute() => DoShouldFlagAMemberWithAnAttribute();
+
+        [Test]
+        public override void ShouldFlagAMemberWithoutAnAttribute() => DoShouldFlagAMemberWithoutAnAttribute();
+
         [Test]
         public override void ShouldRetrievePublicStaticMembers() => DoShouldRetrievePublicStaticMembers();
 

NetStandardPolyfills.UnitTests.Net40/WhenRetrievingTypeProperties.cs

@@ -5,6 +5,18 @@ namespace AgileObjects.NetStandardPolyfills.UnitTests.Net40
     [TestFixture]
     public class WhenRetrievingTypeProperties : PropertyTestsBase
     {
+        [Test]
+        public override void ShouldFlagAReadableProperty() => DoShouldFlagAReadableProperty();
+
+        [Test]
+        public override void ShouldFlagANonReadableProperty() => DoShouldFlagANonReadableProperty();
+
+        [Test]
+        public override void ShouldFlagAWritableProperty() => DoShouldFlagAWritableProperty();
+
+        [Test]
+        public override void ShouldFlagANonWritableProperty() => DoShouldFlagANonWritableProperty();
+
         [Test]
         public override void ShouldRetrievePublicStaticProperties() => DoShouldRetrievePublicStaticProperties();
 

NetStandardPolyfills.UnitTests.NetCore/WhenRetrievingTypeMembers.cs

@@ -4,6 +4,12 @@ namespace AgileObjects.NetStandardPolyfills.UnitTests.NetCore
 
     public class WhenRetrievingTypeMembers : MemberTestsBase
     {
+        [Fact]
+        public override void ShouldFlagAMemberWithAnAttribute() => DoShouldFlagAMemberWithAnAttribute();
+
+        [Fact]
+        public override void ShouldFlagAMemberWithoutAnAttribute() => DoShouldFlagAMemberWithoutAnAttribute();
+
         [Fact]
         public override void ShouldRetrievePublicStaticMembers() => DoShouldRetrievePublicStaticMembers();
 

NetStandardPolyfills.UnitTests.NetCore/WhenRetrievingTypeProperties.cs

@@ -4,6 +4,18 @@ namespace AgileObjects.NetStandardPolyfills.UnitTests.NetCore
 
     public class WhenRetrievingTypeProperties : PropertyTestsBase
     {
+        [Fact]
+        public override void ShouldFlagAReadableProperty() => DoShouldFlagAReadableProperty();
+
+        [Fact]
+        public override void ShouldFlagANonReadableProperty() => DoShouldFlagANonReadableProperty();
+
+        [Fact]
+        public override void ShouldFlagAWritableProperty() => DoShouldFlagAWritableProperty();
+
+        [Fact]
+        public override void ShouldFlagANonWritableProperty() => DoShouldFlagANonWritableProperty();
+
         [Fact]
         public override void ShouldRetrievePublicStaticProperties() => DoShouldRetrievePublicStaticProperties();
 

NetStandardPolyfills.UnitTests/MemberTestsBase.cs

@@ -6,6 +6,10 @@ namespace AgileObjects.NetStandardPolyfills.UnitTests
 
     public abstract class MemberTestsBase
     {
+        public abstract void ShouldFlagAMemberWithAnAttribute();
+
+        public abstract void ShouldFlagAMemberWithoutAnAttribute();
+
         public abstract void ShouldRetrievePublicStaticMembers();
 
         public abstract void ShouldRetrievePublicStaticMembersByName();
@@ -40,6 +44,22 @@ public abstract class MemberTestsBase
 
         #region Test Implementations
 
+        protected void DoShouldFlagAMemberWithAnAttribute()
+        {
+            typeof(TestHelper)
+                .GetPublicInstanceMember(nameof(TestHelper.PublicInstanceProperty))
+                .HasAttribute<MyAttribute>()
+                .ShouldBeTrue();
+        }
+
+        protected void DoShouldFlagAMemberWithoutAnAttribute()
+        {
+            typeof(TestHelper)
+                .GetPublicStaticMember(nameof(TestHelper.PublicStaticProperty))
+                .HasAttribute<MyAttribute>()
+                .ShouldBeFalse();
+        }
+
         protected void DoShouldRetrievePublicStaticMembers()
         {
             var members = typeof(TestHelper)

NetStandardPolyfills.UnitTests/PropertyTestsBase.cs

@@ -5,6 +5,14 @@ namespace AgileObjects.NetStandardPolyfills.UnitTests
 
     public abstract class PropertyTestsBase
     {
+        public abstract void ShouldFlagAReadableProperty();
+
+        public abstract void ShouldFlagANonReadableProperty();
+
+        public abstract void ShouldFlagAWritableProperty();
+
+        public abstract void ShouldFlagANonWritableProperty();
+
         public abstract void ShouldRetrievePublicStaticProperties();
 
         public abstract void ShouldRetrieveAPublicStaticPropertyByName();
@@ -49,6 +57,38 @@ public abstract class PropertyTestsBase
 
         #region Test Implementations
 
+        protected void DoShouldFlagAReadableProperty()
+        {
+            typeof(TestHelper)
+                .GetPublicInstanceProperty(nameof(TestHelper.PublicInstanceProperty))
+                .IsReadable()
+                .ShouldBeTrue();
+        }
+
+        protected void DoShouldFlagANonReadableProperty()
+        {
+            typeof(TestHelper)
+                .GetPublicInstanceProperty(nameof(TestHelper.PublicWriteOnlyProperty))
+                .IsReadable()
+                .ShouldBeFalse();
+        }
+
+        protected void DoShouldFlagAWritableProperty()
+        {
+            typeof(TestHelper)
+                .GetPublicInstanceProperty(nameof(TestHelper.PublicInstanceProperty))
+                .IsWritable()
+                .ShouldBeTrue();
+        }
+
+        protected void DoShouldFlagANonWritableProperty()
+        {
+            typeof(TestHelper)
+                .GetPublicInstanceProperty(nameof(TestHelper.PublicReadOnlyProperty))
+                .IsWritable()
+                .ShouldBeFalse();
+        }
+
         protected void DoShouldRetrievePublicStaticProperties()
         {
             typeof(TestHelper)

NetStandardPolyfills.UnitTests/TestClasses/TestHelper.cs

@@ -14,6 +14,7 @@ public class TestHelper
         internal int NonPublicInstanceField = 0;
         internal static int NonPublicStaticField = 0;
         private readonly Dictionary<string, string> _dictionary;
+        private int _value;
 
         public TestHelper()
         {
@@ -32,8 +33,16 @@ protected TestHelper(string something)
         public static explicit operator int[] (TestHelper testHelper) => new[] { 1, 2, 3 };
         public static explicit operator TestHelper(long value) => new TestHelper();
 
+        [My]
         public int PublicInstanceProperty { get; set; }
 
+        public int PublicReadOnlyProperty => _value;
+
+        public int PublicWriteOnlyProperty
+        {
+            set => _value = value;
+        }
+
         public static int PublicStaticProperty { get; set; }
 
         internal int NonPublicInstanceProperty { get; set; }

NetStandardPolyfills/MemberExtensionsPolyfill.cs

@@ -11,6 +11,29 @@
     /// </summary>
     public static class MemberExtensionsPolyfill
     {
+        /// <summary>
+        /// Returns a value indicating if the <paramref name="memberInfo"/> has the Attribute given
+        /// in the <typeparamref name="TAttribute"/> type argument.
+        /// </summary>
+        /// <typeparam name="TAttribute">The Attribute type for which to make the determination.</typeparam>
+        /// <param name="memberInfo">The MemberInfo for which to make the determination.</param>
+        /// <returns>
+        /// True if the <paramref name="memberInfo"/> has the given <typeparamref name="TAttribute"/>,
+        /// otherwise false.
+        /// </returns>
+        public static bool HasAttribute<TAttribute>(this MemberInfo memberInfo)
+        {
+#if NET_STANDARD
+            return memberInfo
+                .CustomAttributes
+                .Any(a => a.AttributeType == typeof(TAttribute));
+#else
+            return memberInfo
+                .GetCustomAttributes(typeof(TAttribute), inherit: false)
+                .Any();
+#endif
+        }
+
         /// <summary>
         /// Gets the public, static-scoped members for the given <paramref name="type"/>.
         /// </summary>

NetStandardPolyfills/PropertyExtensionsPolyfill.cs

@@ -13,6 +13,20 @@
     /// </summary>
     public static class PropertyExtensionsPolyfill
     {
+        /// <summary>
+        /// Returns a value indicating whether the <paramref name="property"/> is readable.
+        /// </summary>
+        /// <param name="property">The property for which to make the determination.</param>
+        /// <returns>True if the <paramref name="property"/> is readable, otherwise false.</returns>
+        public static bool IsReadable(this PropertyInfo property) => property.GetGetter() != null;
+
+        /// <summary>
+        /// Returns a value indicating whether the <paramref name="property"/> is writable.
+        /// </summary>
+        /// <param name="property">The property for which to make the determination.</param>
+        /// <returns>True if the <paramref name="property"/> is writable, otherwise false.</returns>
+        public static bool IsWritable(this PropertyInfo property) => property.GetSetter() != null;
+
         /// <summary>
         /// Gets the public, static-scoped properties for the given <paramref name="type"/>.
         /// </summary>