Unit Testing Registry access with RhinoMocks and SystemWrapper

As mentioned in the previous Unit Test post (Unit Testing Registry access with RhinoMocks and SystemWrapper) it important to be able to Unit Test code that access the registry without really accessing the registry.

Prerequisites

Step 1 – Download SystemWrapper

You may have already done this when reading the previous post, if not do so now.

  1. Go to https://github.com/jozefizso/SystemWrapper and download the latest dll or the latest source or add the SystemWrapper.Interfaces and SystemWrapper.Wrappers By jozef.izso
  2. Copy the SystemInterface.dll and SystemWrapper.dll into your project (perhaps you already have a libs directory).
  3. Add references to these two dlls in your release code.
  4. Add a reference only to SystemInterface.dll in your Unit Test project.

Step 2 – Change your code to use Interfaces and Wrappers

Ok, so here we are going to start with an example. Here is an object that I wrote myself that uses the registry to check on which versions of .NET Framework are installed. It is currently using Registry and RegistryKey directly.

using System;
using Microsoft.Win32;

namespace SystemInfo
{
    public class DotNetFramework
    {
        #region Constant members
        public const string REGPATH_DOTNET11_VERSION        = @"SOFTWARE\Microsoft\NET Framework Setup\NDP\v1.1.4322";
        public const string REGPATH_DOTNET20_VERSION        = @"SOFTWARE\Microsoft\NET Framework Setup\NDP\v2.0.50727";
        public const string REGPATH_DOTNET30_VERSION        = @"SOFTWARE\Microsoft\NET Framework Setup\NDP\v3.0";
        public const string REGPATH_DOTNET35_VERSION        = @"SOFTWARE\Microsoft\NET Framework Setup\NDP\v3.5";
        public const string REGPATH_DOTNET40_VERSION_CLIENT = @"SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Client";
        public const string REGPATH_DOTNET40_VERSION        = @"SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full";
        #endregion

        #region Properties
        /// <summary>
        /// This returns true if .NET 4 Full is installed.
        /// </summary>
        public bool FoundDotNet4
        {
            get { return HasDotNetFramework(REGPATH_DOTNET40_VERSION, 0); }
        }

        /// <summary>
        /// This returns true if .NET 4 Client is installed.
        /// </summary>
        public bool FoundDotNet4Client
        {
            get { return HasDotNetFramework(REGPATH_DOTNET40_VERSION_CLIENT, 0); }
        }

        /// <summary>
        /// This returns true if .NET 3.5 with SP1 is installed.
        /// </summary>
        public bool FoundDotNet35SP1
        {
            get { return HasDotNetFramework(REGPATH_DOTNET35_VERSION, 1); }
        }

        /// <summary>
        /// This returns true if .NET 3.5 is installed.
        /// </summary>
        public bool FoundDotNet35
        {
            get { return HasDotNetFramework(REGPATH_DOTNET35_VERSION, 0); }
        }

        /// <summary>
        /// This returns true if .NET 3.0 with SP2 is installed.
        /// </summary>
        public bool FoundDotNet30SP2
        {
            get { return HasDotNetFramework(REGPATH_DOTNET30_VERSION, 2); }
        }

        /// <summary>
        /// This returns true if .NET 3.0 with SP1 is installed.
        /// </summary>
        public bool FoundDotNet30SP1
        {
            get { return HasDotNetFramework(REGPATH_DOTNET30_VERSION, 1); }
        }

        /// <summary>
        /// This returns true if .NET 3.0 is installed.
        /// </summary>
        public bool FoundDotNet30
        {
            get { return HasDotNetFramework(REGPATH_DOTNET30_VERSION, 0); }
        }

        /// <summary>
        /// This returns true if .NET 2.0 with SP2 is installed.
        /// </summary>
        public bool FoundDotNet20SP2
        {
            get { return HasDotNetFramework(REGPATH_DOTNET20_VERSION, 2); }
        }

        /// <summary>
        /// This returns true if .NET 2.0 with SP1 is installed.
        /// </summary>
        public bool FoundDotNet20SP1
        {
            get { return HasDotNetFramework(REGPATH_DOTNET20_VERSION, 1); }
        }

        /// <summary>
        /// This returns true if .NET 2.0 is installed.
        /// </summary>
        public bool FoundDotNet20
        {
            get { return HasDotNetFramework(REGPATH_DOTNET20_VERSION, 0); }
        }

        /// <summary>
        /// This returns true if .NET 1.1 is installed.
        /// </summary>
        public bool FoundDotNet11
        {
            get { return HasDotNetFramework(REGPATH_DOTNET11_VERSION, 0); }
        }
        #endregion

        public bool HasDotNetFramework(string dotNetRegPath, int expectedServicePack)
        {
            bool retVal = false;

            try
            {
                RegistryKey localKey = Registry.LocalMachine.OpenSubKey(dotNetRegPath);
                if (localKey != null)
                {
                    int? isInstalled = localKey.GetValue("Install") as int?;
                    if (isInstalled != null)
                    {
                        if (isInstalled == 1)
                        {
                            if (expectedServicePack > 0)
                            {
                                if ((int)localKey.GetValue("SP") >= expectedServicePack)
                                    retVal = true;
                            }
                            else
                            {
                                retVal = true;
                            }
                        }
                    }
                }
                return retVal;
            }
            catch
            {
                return retVal;
            }
        }
    }
}
  1. Find any place in your code where you use touch the system. For example, if you touch the registry, find any place you call Registry or RegistryKey objects or reference Microsoft.Win32.
    Hint: Use the search feature in your IDE.
  2. Replace the reference with a reference to SystemWrapper and SystemInterfaces. For example, if replacingrRegistry code,
    SystemInterface.Microsoft.Win32
    SystemWrapper.Microsoft.Win32In the DotNetFramework.cs file above, there is a using statement to Microsoft.Win32. Our new using statements will be:

    using System;
    using SystemInterface.Microsoft.Win32;
    using SystemWrapper.Microsoft.Win32;
    
  3. For any object that touches the system, change that object to be instantiated using the interface. For example, replace RegistryKey objects with IRegistryKey objects.In the DotNetFramework.cs file, there is only one single line that needs to change to do this, line 113.
    This line…

        RegistryKey localKey = Registry.LocalMachine.OpenSubKey(dotNetRegPath);
    

    …changes to this line.

        IRegistryKey localKey = new RegistryWrap().LocalMachine.OpenSubKey(dotNetRegPath);
    

Step 3 – Allow for replacing the IRegistryKey objects

Create a property or function that allows you to replace the object you are mocking so you can pass in an object that is mocked.

This is done for you to some extent for registry access by using the IAccessTheRegistry interface.

  1. Implementing the IAccessTheRegistry interface from the SystemInterface.Microsoft.Win32 namespace. You can add the following code to the DotNetFramework object.
            #region IAccessTheRegistry Members
    
            public IRegistryKey BaseKey
            {
                get
                {
                    if (null == _BaseKey)
                        _BaseKey = new RegistryWrap().LocalMachine;
                    return _BaseKey;
                }
            } private IRegistryKey _BaseKey;
    
            public void ChangeBaseKey(IRegistryKey inBaseKey)
            {
                _BaseKey = inBaseKey;
            }
    
            #endregion
    

    Note: Notice that the Property is read only. Instead of enabling the set ability, a function is created to allow you to change the IRegistryKey instance. This is by design and keeps you from making a mistake such as BaseKey = BaseKey.OpenSubkey(“…”) and replacing the BaseKey.

    Note: You may want to look into the “Factory” design pattern.

  2. Change line 113 to use the BaseKey.
        IRegistryKey localKey = BaseKey.OpenSubKey(dotNetRegPath);
    

Step 4 – Download and Reference RhinoMocks in your Unit Test

You may have already done this when reading the previous post, if not do so now.

In this step you need to download RhinoMocks and reference it with your Unit Test project. If you don’t have a test project, create one.  Your release project won’t need it.

  1. Go to http://hibernatingrhinos.com/open-source/rhino-mocks and download RhinoMocks.
  2. Add RhinoMocks.dll

Step 5 – Mock IRegistryKey in your Unit Test

For this, you have to understand and know how to use RhinoMocks and this takes some learning. For this we need an example.

  1. Add a new class to your test project.
  2. Add a using statement:
    using&nbsp;Rhino.Mocks;
  3. Add code to create the Mock objects.I put these in separate functions because every test needed the exact same code.
    1. Mock the HKLM key and any calls made using it.
    2. Mock the registry sub key and any calls made using it.
    #region Test Helper Functions
            /// <summary>
            /// Mock to pretend to be this registry subkey:
            /// Hive:   HKLM
            ///
            /// No stubbing is preconfigured
            /// </summary>
            /// <returns>IRegistryKey</returns>
            private IRegistryKey CreateMockOfHKLM()
            {
                // Mock to pretend to be this registry key:
                // Hive:   HKLM
                IRegistryKey hklmMock = MockRepository.GenerateMock<IRegistryKey>();
                hklmMock.Stub(x => x.Name).Return("HKEY_LOCAL_MACHINE");
    
                return hklmMock;
            }
    
            /// <summary>
            /// Mock to pretend to be this registry subkey:
            /// Hive:   HKLM
            ///
            /// It has stubs preconfigured
            /// </summary>
            /// <returns>IRegistry that is a mock of HKLM with IIS Version stubs.</returns>
            private IRegistryKey CreateDotNetRegistryOpenSubKeyMock(string inSubkey, bool inIsInstalled = true, int? inSP = null)
            {
                // Mock to pretend to be this registry subkey:
                // Hive:   HKLM
                IRegistryKey hklmMock = CreateMockOfHKLM();
    
                // Allow to test a key that doesn't exist (null) or one that does.
                IRegistryKey dotNetMock = null;
                if (inIsInstalled)
                {
                    dotNetMock = CreateDotNetRegistryGetValueMock(inSubkey, inSP);
                }
    
                // Stubs using hklmMock to open and return this registry key
                // and return dotNetMock:
                hklmMock.Stub(x => x.OpenSubKey(inSubkey)).Return(dotNetMock);
    
                return hklmMock;
            }
    
            private IRegistryKey CreateDotNetRegistryGetValueMock(string inSubkey, int? inSP)
            {
                // Mock to pretend to be this subkey passed in:
                // Hive:   HKLM
                // SubKey: HKEY_LOCAL_MACHINE\" + inSubkey
                IRegistryKey dotNetMock = MockRepository.GenerateMock<IRegistryKey>();
                dotNetMock.Stub(x => x.Name).Return(@"HKEY_LOCAL_MACHINE\" + inSubkey);
    
                // Stubs checking the available registry properties:
                // Hive:   HKLM
                // SubKey: HKEY_LOCAL_MACHINE\" + inSubkey
                // Properties: "Install", "SP"
                dotNetMock.Stub(x => x.GetValueNames()).Return(new String[] { "Install", "SP" });
    
                // Stubs checking this registry:
                // Hive:   HKLM
                // SubKey: HKEY_LOCAL_MACHINE\" + inSubkey
                // Property: Install
                // Value:  1 - If not installed the whole key shouldn't even exist so it should always be 1
                dotNetMock.Stub(x => x.GetValue("Install")).Return(1);
    
                if (null != inSP)
                {
                    // Stubs checking this registry:
                    // Hive:   HKLM
                    // SubKey: HKEY_LOCAL_MACHINE\" + inSubkey
                    // Property: SP
                    // Value:    null or 1, 2, 3, ...
                    dotNetMock.Stub(x => x.GetValue("SP")).Return(inSP);
                }
                return dotNetMock;
            }
            #endregion
    
  4. Now go forth and mock all your code that uses the Registry.

Here is the final test file.

using System;
using Microsoft.VisualStudio.TestTools.UnitTesting;
using Rhino.Mocks;
using SystemInfo;
using SystemInterface.Microsoft.Win32;

namespace DotNetFrameworkTest
{
    /// <summary>
    ///This is a test class for DotNetFrameworkTest and is intended
    ///to contain all DotNetFrameworkTest Unit Tests
    ///</summary>
    [TestClass()]
    public class DotNetFrameworkTest
    {
        #region Constructor tests
        /// <summary>
        ///A test for DotNetFramework Constructor
        ///</summary>
        [TestMethod()]
        public void DotNetFrameworkConstructorTest()
        {
            DotNetFramework target = new DotNetFramework();
            Assert.IsNotNull(target);
        }
        #endregion

        #region IAccessTheRegistry interface items test
        /// <summary>
        ///A test for ChangeBaseKey
        ///</summary>
        [TestMethod()]
        public void BaseKeyAndChangeBaseKeyTest()
        {
            DotNetFramework target = new DotNetFramework(); // TODO: Initialize to an appropriate value
            IRegistryKey defaultBaseKey = target.BaseKey;
            IRegistryKey inBaseKey = MockRepository.GenerateMock<IRegistryKey>();
            target.ChangeBaseKey(inBaseKey);

            // Make sure the newly assigned is not the same as the original
            Assert.AreNotEqual(target.BaseKey, defaultBaseKey);

            // Make sure that the assignment worked
            Assert.AreEqual(target.BaseKey, inBaseKey);
        }
        #endregion

        #region FoundDotNet11 tests
        /// <summary>
        ///A test for FoundDotNet11 mocking the key so it should return true
        ///</summary>
        [TestMethod()]
        public void FoundDotNet11_Test_KeyExists()
        {
            bool isInstalled = true;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET11_VERSION, isInstalled);
            target.ChangeBaseKey(key);
            bool expected = true;
            bool actual = target.FoundDotNet11;
            Assert.AreEqual(actual, expected);

            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET11_VERSION));
            IRegistryKey innerkey = key.OpenSubKey(DotNetFramework.REGPATH_DOTNET11_VERSION);
            innerkey.AssertWasCalled(x => x.GetValue("Install"));
            innerkey.AssertWasNotCalled(x => x.GetValue("SP"));
        }

        /// <summary>
        ///A test for FoundDotNet11 mocking the lack of a key so it should return false
        ///</summary>
        [TestMethod()]
        public void FoundDotNet11_Test_KeyDoesNotExist()
        {
            bool isInstalled = false;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET11_VERSION, isInstalled);
            target.ChangeBaseKey(key);
            bool expected = false;
            bool actual = target.FoundDotNet11;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET11_VERSION));
            Assert.IsNull(key.OpenSubKey(DotNetFramework.REGPATH_DOTNET11_VERSION));
        }
        #endregion

        #region FoundDotNet20 tests
        /// <summary>
        ///A test for FoundDotNet20 mocking the key so it should return true
        ///</summary>
        [TestMethod()]
        public void FoundDotNet20_Test_KeyExists()
        {
            bool isInstalled = true;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET20_VERSION, isInstalled);
            target.ChangeBaseKey(key);
            bool expected = true;
            bool actual = target.FoundDotNet20;
            Assert.AreEqual(actual, expected);

            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET20_VERSION));
            IRegistryKey innerkey = key.OpenSubKey(DotNetFramework.REGPATH_DOTNET20_VERSION);
            innerkey.AssertWasCalled(x => x.GetValue("Install"));
            innerkey.AssertWasNotCalled(x => x.GetValue("SP"));
        }

        /// <summary>
        ///A test for FoundDotNet20 mocking the lack of a key so it should return false
        ///</summary>
        [TestMethod()]
        public void FoundDotNet20_Test_KeyDoesNotExist()
        {
            bool isInstalled = false;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET20_VERSION, isInstalled);
            target.ChangeBaseKey(key);
            bool expected = false;
            bool actual = target.FoundDotNet20;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET20_VERSION));
            Assert.IsNull(key.OpenSubKey(DotNetFramework.REGPATH_DOTNET20_VERSION));
        }
        #endregion

        #region FoundDOtNet20SP1 tests
        /// <summary>
        ///A test for FoundDotNet20SP1 mocking the key so it should return true
        ///</summary>
        [TestMethod()]
        public void FoundDotNet20SP1_Test_KeyExistsWithSP1()
        {
            bool isInstalled = true;
            int? sp = 1;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET20_VERSION, isInstalled, sp);
            target.ChangeBaseKey(key);
            bool expected = true;
            bool actual = target.FoundDotNet20SP1;
            
            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET20_VERSION));
            IRegistryKey innerkey = key.OpenSubKey(DotNetFramework.REGPATH_DOTNET20_VERSION);
            innerkey.AssertWasCalled(x => x.GetValue("Install"));
            innerkey.AssertWasCalled(x => x.GetValue("SP"));
        }

        /// <summary>
        ///A test for FoundDotNet20SP1 mocking the key so it should return false due to no service pack
        ///</summary>
        [TestMethod()]
        public void FoundDotNet20SP1_Test_KeyExistsWithoutSP1()
        {
            bool isInstalled = true;
            int? sp = null;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET20_VERSION, isInstalled, sp);
            target.ChangeBaseKey(key);
            bool expected = false;
            bool actual = target.FoundDotNet20SP1;
            
            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET20_VERSION));
            IRegistryKey innerkey = key.OpenSubKey(DotNetFramework.REGPATH_DOTNET20_VERSION);
            innerkey.AssertWasCalled(x => x.GetValue("Install"));
            innerkey.AssertWasCalled(x => x.GetValue("SP"));
        }

        /// <summary>
        ///A test for FoundDotNet20SP1 mocking the lack of a key so it should return false
        ///</summary>
        [TestMethod()]
        public void FoundDotNet20SP1_Test_KeyDoesNotExist()
        {
            bool isInstalled = false;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET20_VERSION, isInstalled);
            target.ChangeBaseKey(key);
            bool expected = false;
            bool actual = target.FoundDotNet20SP1;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET20_VERSION));
            Assert.IsNull(key.OpenSubKey(DotNetFramework.REGPATH_DOTNET20_VERSION));
        }
        #endregion

        #region FoundDOtNet20SP2 tests
        /// <summary>
        ///A test for FoundDotNet20SP2 mocking the key so it should return true
        ///</summary>
        [TestMethod()]
        public void FoundDotNet20SP2_Test_KeyExistsWithSP2()
        {
            bool isInstalled = true;
            int? sp = 2;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET20_VERSION, isInstalled, sp);
            target.ChangeBaseKey(key);
            bool expected = true;
            bool actual = target.FoundDotNet20SP2;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET20_VERSION));
            IRegistryKey innerkey = key.OpenSubKey(DotNetFramework.REGPATH_DOTNET20_VERSION);
            innerkey.AssertWasCalled(x => x.GetValue("Install"));
            innerkey.AssertWasCalled(x => x.GetValue("SP"));
        }

        /// <summary>
        ///A test for FoundDotNet20SP2 mocking the key so it should return false because it only has SP1
        ///</summary>
        [TestMethod()]
        public void FoundDotNet20SP2_Test_KeyExistsWithSP1()
        {
            bool isInstalled = true;
            int? sp = 1;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET20_VERSION, isInstalled, sp);
            target.ChangeBaseKey(key);
            bool expected = false;
            bool actual = target.FoundDotNet20SP2;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET20_VERSION));
            IRegistryKey innerkey = key.OpenSubKey(DotNetFramework.REGPATH_DOTNET20_VERSION);
            innerkey.AssertWasCalled(x => x.GetValue("Install"));
            innerkey.AssertWasCalled(x => x.GetValue("SP"));
        }

        /// <summary>
        ///A test for FoundDotNet20SP2 mocking the key so it should return false due to no service pack
        ///</summary>
        [TestMethod()]
        public void FoundDotNet20SP2_Test_KeyExistsWithoutSP()
        {
            bool isInstalled = true;
            int? sp = null;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET20_VERSION, isInstalled, sp);
            target.ChangeBaseKey(key);
            bool expected = false;
            bool actual = target.FoundDotNet20SP2;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET20_VERSION));
            IRegistryKey innerkey = key.OpenSubKey(DotNetFramework.REGPATH_DOTNET20_VERSION);
            innerkey.AssertWasCalled(x => x.GetValue("Install"));
            innerkey.AssertWasCalled(x => x.GetValue("SP"));
        }

        /// <summary>
        ///A test for FoundDotNet20SP2 mocking the lack of a key so it should return false
        ///</summary>
        [TestMethod()]
        public void FoundDotNet20SP2_Test_KeyDoesNotExist()
        {
            bool isInstalled = false;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET20_VERSION, isInstalled);
            target.ChangeBaseKey(key);
            bool expected = false;
            bool actual = target.FoundDotNet20SP2;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET20_VERSION));
            Assert.IsNull(key.OpenSubKey(DotNetFramework.REGPATH_DOTNET20_VERSION));
        }
        #endregion

        #region FoundDotNet30 tests
        /// <summary>
        ///A test for FoundDotNet30 mocking the key so it should return true
        ///</summary>
        [TestMethod()]
        public void FoundDotNet30_Test_KeyExists()
        {
            bool isInstalled = true;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET30_VERSION, isInstalled);
            target.ChangeBaseKey(key);
            bool expected = true;
            bool actual = target.FoundDotNet30;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET30_VERSION));
            IRegistryKey innerkey = key.OpenSubKey(DotNetFramework.REGPATH_DOTNET30_VERSION);
            innerkey.AssertWasCalled(x => x.GetValue("Install"));
            innerkey.AssertWasNotCalled(x => x.GetValue("SP"));
        }

        /// <summary>
        ///A test for FoundDotNet30 mocking the lack of a key so it should return false
        ///</summary>
        [TestMethod()]
        public void FoundDotNet30_Test_KeyDoesNotExist()
        {
            bool isInstalled = false;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET30_VERSION, isInstalled);
            target.ChangeBaseKey(key);
            bool expected = false;
            bool actual = target.FoundDotNet30;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET30_VERSION));
            Assert.IsNull(key.OpenSubKey(DotNetFramework.REGPATH_DOTNET30_VERSION));
        }
        #endregion

        #region FoundDOtNet30SP1 tests
        /// <summary>
        ///A test for FoundDotNet30SP1 mocking the key so it should return true
        ///</summary>
        [TestMethod()]
        public void FoundDotNet30SP1_Test_KeyExistsWithSP1()
        {
            bool isInstalled = true;
            int? sp = 1;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET30_VERSION, isInstalled, sp);
            target.ChangeBaseKey(key);
            bool expected = true;
            bool actual = target.FoundDotNet30SP1;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET30_VERSION));
            IRegistryKey innerkey = key.OpenSubKey(DotNetFramework.REGPATH_DOTNET30_VERSION);
            innerkey.AssertWasCalled(x => x.GetValue("Install"));
            innerkey.AssertWasCalled(x => x.GetValue("SP"));
        }

        /// <summary>
        ///A test for FoundDotNet30SP1 mocking the key so it should return false due to no service pack
        ///</summary>
        [TestMethod()]
        public void FoundDotNet30SP1_Test_KeyExistsWithoutSP()
        {
            bool isInstalled = true;
            int? sp = null;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET30_VERSION, isInstalled, sp);
            target.ChangeBaseKey(key);
            bool expected = false;
            bool actual = target.FoundDotNet30SP1;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET30_VERSION));
            IRegistryKey innerkey = key.OpenSubKey(DotNetFramework.REGPATH_DOTNET30_VERSION);
            innerkey.AssertWasCalled(x => x.GetValue("Install"));
            innerkey.AssertWasCalled(x => x.GetValue("SP"));
        }

        /// <summary>
        ///A test for FoundDotNet30SP1 mocking the lack of a key so it should return false
        ///</summary>
        [TestMethod()]
        public void FoundDotNet30SP1_Test_KeyDoesNotExist()
        {
            bool isInstalled = false;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET30_VERSION, isInstalled);
            target.ChangeBaseKey(key);
            bool expected = false;
            bool actual = target.FoundDotNet30SP1;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET30_VERSION));
            Assert.IsNull(key.OpenSubKey(DotNetFramework.REGPATH_DOTNET30_VERSION));
        }
        #endregion

        #region FoundDOtNet30SP2 tests
        /// <summary>
        ///A test for FoundDotNet30SP2 mocking the key so it should return true
        ///</summary>
        [TestMethod()]
        public void FoundDotNet30SP2_Test_KeyExistsWithSP2()
        {
            bool isInstalled = true;
            int? sp = 2;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET30_VERSION, isInstalled, sp);
            target.ChangeBaseKey(key);
            bool expected = true;
            bool actual = target.FoundDotNet30SP2;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET30_VERSION));
            IRegistryKey innerkey = key.OpenSubKey(DotNetFramework.REGPATH_DOTNET30_VERSION);
            innerkey.AssertWasCalled(x => x.GetValue("Install"));
            innerkey.AssertWasCalled(x => x.GetValue("SP"));
        }

        /// <summary>
        ///A test for FoundDotNet30SP2 mocking the key so it should return false because it only has SP1
        ///</summary>
        [TestMethod()]
        public void FoundDotNet30SP2_Test_KeyExistsWithSP1()
        {
            bool isInstalled = true;
            int? sp = 1;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET30_VERSION, isInstalled, sp);
            target.ChangeBaseKey(key);
            bool expected = false;
            bool actual = target.FoundDotNet30SP2;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET30_VERSION));
            IRegistryKey innerkey = key.OpenSubKey(DotNetFramework.REGPATH_DOTNET30_VERSION);
            innerkey.AssertWasCalled(x => x.GetValue("Install"));
            innerkey.AssertWasCalled(x => x.GetValue("SP"));
        }

        /// <summary>
        ///A test for FoundDotNet30SP2 mocking the key so it should return false due to no service pack
        ///</summary>
        [TestMethod()]
        public void FoundDotNet30SP2_Test_KeyExistsWithoutSP()
        {
            bool isInstalled = true;
            int? sp = null;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET30_VERSION, isInstalled, sp);
            target.ChangeBaseKey(key);
            bool expected = false;
            bool actual = target.FoundDotNet30SP2;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET30_VERSION));
            IRegistryKey innerkey = key.OpenSubKey(DotNetFramework.REGPATH_DOTNET30_VERSION);
            innerkey.AssertWasCalled(x => x.GetValue("Install"));
            innerkey.AssertWasCalled(x => x.GetValue("SP"));
        }

        /// <summary>
        ///A test for FoundDotNet30SP2 mocking the lack of a key so it should return false
        ///</summary>
        [TestMethod()]
        public void FoundDotNet30SP2_Test_KeyDoesNotExist()
        {
            bool isInstalled = false;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET30_VERSION, isInstalled);
            target.ChangeBaseKey(key);
            bool expected = false;
            bool actual = target.FoundDotNet30SP2;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET30_VERSION));
            Assert.IsNull(key.OpenSubKey(DotNetFramework.REGPATH_DOTNET30_VERSION));
        }
        #endregion
        
        #region FoundDotNet35 tests
        /// <summary>
        ///A test for FoundDotNet35 mocking the key so it should return true
        ///</summary>
        [TestMethod()]
        public void FoundDotNet35_Test_KeyExists()
        {
            bool isInstalled = true;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET35_VERSION, isInstalled);
            target.ChangeBaseKey(key);
            bool expected = true;
            bool actual = target.FoundDotNet35;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET35_VERSION));
            IRegistryKey innerkey = key.OpenSubKey(DotNetFramework.REGPATH_DOTNET35_VERSION);
            innerkey.AssertWasCalled(x => x.GetValue("Install"));
            innerkey.AssertWasNotCalled(x => x.GetValue("SP"));
        }

        /// <summary>
        ///A test for FoundDotNet35 mocking the lack of a key so it should return false
        ///</summary>
        [TestMethod()]
        public void FoundDotNet35_Test_KeyDoesNotExist()
        {
            bool isInstalled = false;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET35_VERSION, isInstalled);
            target.ChangeBaseKey(key);
            bool expected = false;
            bool actual = target.FoundDotNet35;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET35_VERSION));
            Assert.IsNull(key.OpenSubKey(DotNetFramework.REGPATH_DOTNET35_VERSION));
        }
        #endregion

        #region FoundDOtNet35SP1 tests
        /// <summary>
        ///A test for FoundDotNet35SP1 mocking the key so it should return true
        ///</summary>
        [TestMethod()]
        public void FoundDotNet35SP1_Test_KeyExistsWithSP1()
        {
            bool isInstalled = true;
            int? sp = 1;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET35_VERSION, isInstalled, sp);
            target.ChangeBaseKey(key);
            bool expected = true;
            bool actual = target.FoundDotNet35SP1;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET35_VERSION));
            IRegistryKey innerkey = key.OpenSubKey(DotNetFramework.REGPATH_DOTNET35_VERSION);
            innerkey.AssertWasCalled(x => x.GetValue("Install"));
            innerkey.AssertWasCalled(x => x.GetValue("SP"));
        }

        /// <summary>
        ///A test for FoundDotNet35SP1 mocking the key so it should return false due to no service pack
        ///</summary>
        [TestMethod()]
        public void FoundDotNet35SP1_Test_KeyExistsWithoutSP()
        {
            bool isInstalled = true;
            int? sp = null;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET35_VERSION, isInstalled, sp);
            target.ChangeBaseKey(key);
            bool expected = false;
            bool actual = target.FoundDotNet35SP1;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET35_VERSION));
            IRegistryKey innerkey = key.OpenSubKey(DotNetFramework.REGPATH_DOTNET35_VERSION);
            innerkey.AssertWasCalled(x => x.GetValue("Install"));
            innerkey.AssertWasCalled(x => x.GetValue("SP"));
        }

        /// <summary>
        ///A test for FoundDotNet35SP1 mocking the lack of a key so it should return false
        ///</summary>
        [TestMethod()]
        public void FoundDotNet35SP1_Test_KeyDoesNotExist()
        {
            bool isInstalled = false;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET35_VERSION, isInstalled);
            target.ChangeBaseKey(key);
            bool expected = false;
            bool actual = target.FoundDotNet35SP1;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET35_VERSION));
            Assert.IsNull(key.OpenSubKey(DotNetFramework.REGPATH_DOTNET35_VERSION));
        }
        #endregion

        #region FoundDotNet 4 Full tests
        /// <summary>
        ///A test for FoundDotNet4 (full) mocking the key so it should return true
        ///</summary>
        [TestMethod()]
        public void FoundDotNet4_Full_Test_KeyExists()
        {
            bool isInstalled = true;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET40_VERSION, isInstalled);
            target.ChangeBaseKey(key);
            bool expected = true;
            bool actual = target.FoundDotNet4;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET40_VERSION));
            IRegistryKey innerkey = key.OpenSubKey(DotNetFramework.REGPATH_DOTNET40_VERSION);
            innerkey.AssertWasCalled(x => x.GetValue("Install"));
            innerkey.AssertWasNotCalled(x => x.GetValue("SP"));
        }

        /// <summary>
        ///A test for FoundDotNet4 (full) mocking the lack of a key so it should return false
        ///</summary>
        [TestMethod()]
        public void FoundDotNet4_Test_KeyDoesNotExist()
        {
            bool isInstalled = false;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET40_VERSION, isInstalled);
            target.ChangeBaseKey(key);
            bool expected = false;
            bool actual = target.FoundDotNet4;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET40_VERSION));
            Assert.IsNull(key.OpenSubKey(DotNetFramework.REGPATH_DOTNET40_VERSION));
        }
        #endregion

        #region FoundDotNet4 Client tests
        /// <summary>
        ///A test for FoundDotNet4Client mocking the key so it should return true
        ///</summary>
        [TestMethod()]
        public void FoundDotNet4Client_Test_KeyExists()
        {
            bool isInstalled = true;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET40_VERSION_CLIENT, isInstalled);
            target.ChangeBaseKey(key);
            bool expected = true;
            bool actual = target.FoundDotNet4Client;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET40_VERSION_CLIENT));
            IRegistryKey innerkey = key.OpenSubKey(DotNetFramework.REGPATH_DOTNET40_VERSION_CLIENT);
            innerkey.AssertWasCalled(x => x.GetValue("Install"));
            innerkey.AssertWasNotCalled(x => x.GetValue("SP"));
        }

        /// <summary>
        ///A test for FoundDotNet4 (client) mocking the lack of a key so it should return false
        ///</summary>
        [TestMethod()]
        public void FoundDotNet4Client_Test_KeyDoesNotExist()
        {
            bool isInstalled = false;
            DotNetFramework target = new DotNetFramework();
            IRegistryKey key = CreateDotNetRegistryOpenSubKeyMock(DotNetFramework.REGPATH_DOTNET40_VERSION_CLIENT, isInstalled);
            target.ChangeBaseKey(key);
            bool expected = false;
            bool actual = target.FoundDotNet4Client;

            Assert.AreEqual(actual, expected);
            key.AssertWasCalled(x => x.OpenSubKey(DotNetFramework.REGPATH_DOTNET40_VERSION_CLIENT));
            Assert.IsNull(key.OpenSubKey(DotNetFramework.REGPATH_DOTNET40_VERSION_CLIENT));
        }
        #endregion

        #region HasDotNetFrameworkTest
        /// <summary>
        ///A test for HasDotNetFramework
        ///</summary>
        [TestMethod()]
        public void HasDotNetFrameworkTest()
        {
            // No need to test this as all properties test this
        }

        #endregion

        #region Test Helper Functions
        /// <summary>
        /// Mock to pretend to be this registry subkey:
        /// Hive:   HKLM
        /// 
        /// No stubbing is preconfigured
        /// </summary>
        /// <returns>IRegistryKey</returns>
        private IRegistryKey CreateMockOfHKLM()
        {
            // Mock to pretend to be this registry key:
            // Hive:   HKLM
            IRegistryKey hklmMock = MockRepository.GenerateMock<IRegistryKey>();
            hklmMock.Stub(x => x.Name).Return("HKEY_LOCAL_MACHINE");

            return hklmMock;
        }

        /// <summary>
        /// Mock to pretend to be this registry subkey:
        /// Hive:   HKLM
        /// 
        /// It has stubs preconfigured
        /// </summary>
        /// <returns>IRegistry that is a mock of HKLM with IIS Version stubs.</returns>
        private IRegistryKey CreateDotNetRegistryOpenSubKeyMock(string inSubkey, bool inIsInstalled = true, int? inSP = null)
        {
            // Mock to pretend to be this registry subkey:
            // Hive:   HKLM
            IRegistryKey hklmMock = CreateMockOfHKLM();

            // Allow to test a key that doesn't exist (null) or one that does.
            IRegistryKey dotNetMock = null;
            if (inIsInstalled)
            {
                dotNetMock = CreateDotNetRegistryGetValueMock(inSubkey, inSP);
            }

            // Stubs using hklmMock to open and return this registry key
            // and return dotNetMock:
            hklmMock.Stub(x => x.OpenSubKey(inSubkey)).Return(dotNetMock);
            
            return hklmMock;
        }

        private IRegistryKey CreateDotNetRegistryGetValueMock(string inSubkey, int? inSP)
        {
            // Mock to pretend to be this subkey passed in:
            // Hive:   HKLM
            // SubKey: HKEY_LOCAL_MACHINE\" + inSubkey
            IRegistryKey dotNetMock = MockRepository.GenerateMock<IRegistryKey>();
            dotNetMock.Stub(x => x.Name).Return(@"HKEY_LOCAL_MACHINE\" + inSubkey);

            // Stubs checking the available registry properties:
            // Hive:   HKLM
            // SubKey: HKEY_LOCAL_MACHINE\" + inSubkey
            // Properties: "Install", "SP"
            dotNetMock.Stub(x => x.GetValueNames()).Return(new String[] { "Install", "SP" });

            // Stubs checking this registry:
            // Hive:   HKLM
            // SubKey: HKEY_LOCAL_MACHINE\" + inSubkey
            // Property: Install
            // Value:  1 - If not installed the whole key shouldn't even exist so it should always be 1
            dotNetMock.Stub(x => x.GetValue("Install")).Return(1);

            if (null != inSP)
            {
                // Stubs checking this registry:
                // Hive:   HKLM
                // SubKey: HKEY_LOCAL_MACHINE\" + inSubkey
                // Property: SP
                // Value:    null or 1, 2, 3, ...
                dotNetMock.Stub(x => x.GetValue("SP")).Return(inSP);
            }
            return dotNetMock;
        }
        #endregion

    }
}

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8 Comments

  1. […] http://www.rhyous.com/2011/11/04/unit-testing-registry-access-with-rhinomocks-and-systemwrapper/ […]

  2. harlan says:

    I cannot find the systeminterface.dll,can you help me please?

    • Rhyous says:

      I think you have to check out the .NET 4 version and build it. I don't think the main developers of the project have created a release since I made the .NET 4 version and enhanced it some.

      • harlan says:

        Thanks very much.I have got the dll,but when I changed the code like below.
        IRegistryKey localKey = new RegistryWrap().LocalMachine.OpenSubKey(dotNetRegPath);
        there is error as follows.
        Error 1 Cannot implicitly convert type 'SystemWrapper.Microsoft.Win32.IRegistryKeyWrap' to 'SystemInterface.Microsoft.Win32.IRegistryKey'. An explicit conversion exists (are you missing a cast?) C:\VS2012\Unit Tests\MockRegistry\MockRegistry\DotNetFramework\DotNetFramework.cs 120 41 DotNetFramework

        could you please give some tips?

  3. [...] Unit Testing Registry access with RhinoMocks and SystemWrapper [...]

  4. Vadim says:

    Nice post. Keep spreading the word about SystemWrapper.

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