Handle protected and internal property setters

src/NSubstitute/Core/PropertyHelper.cs

@@ -25,7 +25,7 @@ public bool IsCallToSetAReadWriteProperty(ICall call)
 
         private bool PropertySetterExistsAndHasAGetMethod(PropertyInfo propertySetter)
         {
-            return propertySetter != null && propertySetter.GetGetMethod() != null;
+            return propertySetter != null && propertySetter.GetGetMethod(nonPublic: true) != null;
         }
 
         private PropertyInfo GetPropertyFromSetterCallOrNull(ICall call)
@@ -41,7 +41,7 @@ public ICall CreateCallToPropertyGetterFromSetterCall(ICall callToSetter)
                 throw new InvalidOperationException("Could not find a GetMethod for \"" + callToSetter.GetMethodInfo() + "\"");
             }
 
-            var getter = propertyInfo.GetGetMethod();
+            var getter = propertyInfo.GetGetMethod(nonPublic: true);
             var getterArgs = SkipLast(callToSetter.GetOriginalArguments());
             var getterArgumentSpecifications = GetGetterCallSpecificationsFromSetterCall(callToSetter);
 

src/NSubstitute/Core/ReflectionExtensions.cs

@@ -10,26 +10,24 @@ public static PropertyInfo GetPropertyFromSetterCallOrNull(this MethodInfo call)
         {
             if (!CanBePropertySetterCall(call)) return null;
 
-            var properties = call.DeclaringType.GetProperties();
-
             // Don't use .FirstOrDefault() lambda, as closure leads to allocation even if not reached.
-            foreach (var property in properties)
+            foreach (var property in GetAllProperties(call.DeclaringType))
             {
-                if (property.GetSetMethod() == call) return property;
+                if (property.GetSetMethod(nonPublic: true) == call) return property;
             }
 
             return null;
         }
 
         public static PropertyInfo GetPropertyFromGetterCallOrNull(this MethodInfo call)
         {
-            var properties = call.DeclaringType.GetProperties();
-            return properties.FirstOrDefault(x => x.GetGetMethod() == call);
+            return GetAllProperties(call.DeclaringType)
+                .FirstOrDefault(x => x.GetGetMethod(nonPublic: true) == call);
         }
 
         public static bool IsParams(this ParameterInfo parameterInfo)
         {
-            return parameterInfo.IsDefined(typeof(ParamArrayAttribute), false);
+            return parameterInfo.IsDefined(typeof(ParamArrayAttribute), inherit: false);
         }
 
         private static bool CanBePropertySetterCall(MethodInfo call)
@@ -42,5 +40,11 @@ private static bool CanBePropertySetterCall(MethodInfo call)
             // misbehaves in those cases. We use slightly slower, but robust check.
             return call.Name.StartsWith("set_", StringComparison.Ordinal);
         }
+
+        private static PropertyInfo[] GetAllProperties(Type type)
+        {
+            // return type.GetProperties();
+            return type.GetProperties(BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
+        }
     }
 }

tests/NSubstitute.Acceptance.Specs/FieldReports/Issue262_NonPublicSetterCall.cs

@@ -0,0 +1,53 @@
+using NUnit.Framework;
+
+namespace NSubstitute.Acceptance.Specs.FieldReports
+{
+    /// <summary>
+    /// Scenarios for the issue: https://github.com/nsubstitute/NSubstitute/issues/626
+    ///
+    /// Do not test internal members, as we don't want to set InternalsVisibleTo attribute.
+    /// </summary>
+    public class Issue262_NonPublicSetterCall
+    {
+        [Test]
+        public void ShouldHandleProtectedProperties()
+        {
+            var substitute = Substitute.For<TestClass>();
+
+            substitute.ProtectedPropProxy = 42;
+
+            var result = substitute.ProtectedPropProxy;
+            Assert.That(result, Is.EqualTo(expected: 42));
+            substitute.Received().ProtectedPropProxy = Arg.Any<int>();
+        }
+
+        [Test]
+        public void ShouldHandlePropertiesWithDifferentAccessorVisibility()
+        {
+            var subs = Substitute.For<TestClass>();
+
+            subs.PublicGetProtectedSetPropSetter = 42;
+
+            var result = subs.PublicGetProtectedSetProp;
+            Assert.That(result, Is.EqualTo(expected: 42));
+        }
+
+        public abstract class TestClass
+        {
+            protected abstract int ProtectedProp { get; set; }
+
+            public int ProtectedPropProxy
+            {
+                get => ProtectedProp;
+                set => ProtectedProp = value;
+            }
+
+            public abstract int PublicGetProtectedSetProp { get; protected set; }
+
+            public int PublicGetProtectedSetPropSetter
+            {
+                set => PublicGetProtectedSetProp = value;
+            }
+        }
+    }
+}