Add support for indexers

Documentation/Tutorial.md

@@ -105,6 +105,28 @@ var stub = new StubIPhoneBook()
     .MyNumber_Set(value => newNumber = value);
 ```
 
+## Stubbing indexers
+```csharp
+var stub = new StubIGenericContainer<int>();
+
+// stubbing indexer getter
+stub.Item_Get(index =>
+{
+    // we're expecting the code under test to get index 5
+    if (index != 5) throw new IndexOutOfRangeException();
+    return 99;
+});
+
+// stubbing indexer setter
+int res = -1;
+stub.Item_Set((index, value) =>
+{
+    // we're expecting the code under test to only set index 7
+    if (index != 7) throw new IndexOutOfRangeException();
+    res = value;
+});
+```
+
 ## Stubbing events
 
 ```csharp

NuGet/SimpleStubs.nuspec

@@ -2,7 +2,7 @@
 <package >
   <metadata>
     <id>Etg.SimpleStubs</id>
-    <version>2.2.0</version>
+    <version>2.3.0</version>
     <title>SimpleStubs mocking framework</title>
     <authors>Microsoft Studios (BigPark)</authors>
     <owners>Microsoft Studios (BigPark)</owners>

src/SimpleStubs.CodeGen/CodeGen/IPropertyStubber.cs

@@ -0,0 +1,11 @@
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp.Syntax;
+
+namespace Etg.SimpleStubs.CodeGen
+{
+    internal interface IPropertyStubber
+    {
+        ClassDeclarationSyntax StubProperty(ClassDeclarationSyntax classDclr, IPropertySymbol propertySymbol,
+            INamedTypeSymbol stubbedInterface);
+    }
+}

src/SimpleStubs.CodeGen/CodeGen/InterfaceStubber.cs

@@ -12,9 +12,11 @@ namespace Etg.SimpleStubs.CodeGen
     internal class InterfaceStubber : IInterfaceStubber
     {
         private readonly IEnumerable<IMethodStubber> _methodStubbers;
+        private readonly IEnumerable<IPropertyStubber> _propertyStubbers; 
 
-        public InterfaceStubber(IEnumerable<IMethodStubber> methodStubbers)
+        public InterfaceStubber(IEnumerable<IMethodStubber> methodStubbers, IEnumerable<IPropertyStubber> propertyStubbers)
         {
+            _propertyStubbers = propertyStubbers;
             _methodStubbers = new List<IMethodStubber>(methodStubbers);
         }
 
@@ -32,6 +34,7 @@ namespace Etg.SimpleStubs.CodeGen
 
             classDclr = RoslynUtils.CopyGenericConstraints(interfaceType, classDclr);
             classDclr = AddStubContainerField(classDclr, stubName);
+            classDclr = StubProperties(interfaceType, classDclr);
             classDclr = StubMethods(interfaceType, classDclr);
 
             string fullNameSpace = semanticModel.GetDeclaredSymbol(namespaceNode).ToString();
@@ -42,9 +45,22 @@ namespace Etg.SimpleStubs.CodeGen
             return cu;
         }
 
+        private ClassDeclarationSyntax StubProperties(INamedTypeSymbol interfaceType, ClassDeclarationSyntax classDclr)
+        {
+            IEnumerable<IPropertySymbol> propertiesToStub = RoslynUtils.GetAllMembers<IPropertySymbol>(interfaceType);
+            foreach (IPropertySymbol propertySymbol in propertiesToStub)
+            {
+                foreach (IPropertyStubber propertyStubber in _propertyStubbers)
+                {
+                    classDclr = propertyStubber.StubProperty(classDclr, propertySymbol, interfaceType);
+                }
+            }
+            return classDclr;
+        }
+
         private ClassDeclarationSyntax StubMethods(INamedTypeSymbol interfaceType, ClassDeclarationSyntax classDclr)
         {
-            List<IMethodSymbol> methodsToStub = RoslynUtils.GetAllMethods(interfaceType);
+            IEnumerable<IMethodSymbol> methodsToStub = RoslynUtils.GetAllMembers<IMethodSymbol>(interfaceType);
             foreach (IMethodSymbol methodSymbol in methodsToStub)
             {
                 foreach (IMethodStubber methodStubber in _methodStubbers)

src/SimpleStubs.CodeGen/CodeGen/OrdinaryMethodStubber.cs

@@ -27,7 +27,7 @@ namespace Etg.SimpleStubs.CodeGen
                         SF.IdentifierName(methodSymbol.GetContainingInterfaceGenericQualifiedName())));
 
             string delegateTypeName = NamingUtils.GetDelegateTypeName(methodSymbol, stubbedInterface);
-            string parameters = FormatParameters(methodSymbol);
+            string parameters = StubbingUtils.FormatParameters(methodSymbol);
 
             string callDelegateStmt = StubbingUtils.GenerateInvokeDelegateStmt(delegateTypeName, methodSymbol.GetGenericName(), parameters);
             if (!methodSymbol.ReturnsVoid)
@@ -40,21 +40,5 @@ namespace Etg.SimpleStubs.CodeGen
 
             return classDclr;
         }
-
-	    private static string FormatParameters(IMethodSymbol methodSymbol)
-	    {
-		    return string.Join(", ", methodSymbol.Parameters.Select(p =>
-		    {
-			    if (p.RefKind == RefKind.Out)
-			    {
-				    return $"out {p.Name}";
-			    }
-			    if (p.RefKind == RefKind.Ref)
-			    {
-				    return $"ref {p.Name}";
-			    }
-			    return p.Name;
-		    }));
-	    }
     }
 }

src/SimpleStubs.CodeGen/CodeGen/PropertyStubber.cs

@@ -1,79 +1,75 @@
-using System;
-using Microsoft.CodeAnalysis;
-using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Etg.SimpleStubs.CodeGen.Utils;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
+using Microsoft.CodeAnalysis.CSharp.Syntax;
 
 namespace Etg.SimpleStubs.CodeGen
 {
-    using Microsoft.CodeAnalysis.CSharp;
-    using System.Linq;
-    using SF = Microsoft.CodeAnalysis.CSharp.SyntaxFactory;
+    using SF = SyntaxFactory;
 
-    internal class PropertyStubber : IMethodStubber
+    internal class PropertyStubber : IPropertyStubber
     {
-        public ClassDeclarationSyntax StubMethod(ClassDeclarationSyntax classDclr, IMethodSymbol methodSymbol,
+        public ClassDeclarationSyntax StubProperty(ClassDeclarationSyntax classDclr, IPropertySymbol propertySymbol,
             INamedTypeSymbol stubbedInterface)
         {
-            if (!methodSymbol.IsPropertyAccessor())
-            {
-                return classDclr;
-            }
+            string indexerType = propertySymbol.Type.ToDisplayString(SymbolDisplayFormat.FullyQualifiedFormat);
+            BasePropertyDeclarationSyntax propDclr = null;
 
-            string delegateTypeName = NamingUtils.GetDelegateTypeName(methodSymbol, stubbedInterface);
-
-            string propName = methodSymbol.AssociatedSymbol.Name;
-            string propType =
-                ((IPropertySymbol) methodSymbol.AssociatedSymbol).Type.ToDisplayString(
-                    SymbolDisplayFormat.FullyQualifiedFormat);
-            var propDclr = GetPropDclr(classDclr, propName);
-            if (propDclr == null)
+            if (propertySymbol.GetMethod != null)
             {
-                propDclr = SF.PropertyDeclaration(SF.ParseTypeName(propType), SF.Identifier(propName))
-                    .WithExplicitInterfaceSpecifier(SF.ExplicitInterfaceSpecifier(
-                        SF.IdentifierName(methodSymbol.GetContainingInterfaceGenericQualifiedName())));
-            }
+                IMethodSymbol getMethodSymbol = propertySymbol.GetMethod;
+                string parameters = StubbingUtils.FormatParameters(getMethodSymbol);
 
-            if (methodSymbol.IsPropertyGetter())
-            {
+                string delegateTypeName = NamingUtils.GetDelegateTypeName(getMethodSymbol, stubbedInterface);
                 var accessorDclr = SF.AccessorDeclaration(SyntaxKind.GetAccessorDeclaration, SF.Block(
                     SF.List(new[]
                     {
-                        SF.ParseStatement("return " + StubbingUtils.GenerateInvokeDelegateStmt(delegateTypeName, methodSymbol.Name, ""))
+                        SF.ParseStatement("return " + StubbingUtils.GenerateInvokeDelegateStmt(delegateTypeName, getMethodSymbol.Name, parameters))
                     })));
+
+                propDclr = CreatePropertyDclr(getMethodSymbol, indexerType);
                 propDclr = propDclr.AddAccessorListAccessors(accessorDclr);
+                
             }
-            else if (methodSymbol.IsPropertySetter())
+            if (propertySymbol.SetMethod != null)
             {
+                IMethodSymbol setMethodSymbol = propertySymbol.SetMethod;
+                string parameters = $"{StubbingUtils.FormatParameters(setMethodSymbol)}";
+                string delegateTypeName = NamingUtils.GetDelegateTypeName(setMethodSymbol, stubbedInterface);
                 var accessorDclr = SF.AccessorDeclaration(SyntaxKind.SetAccessorDeclaration, SF.Block(
                     SF.List(new[]
                     {
-                        SF.ParseStatement(StubbingUtils.GenerateInvokeDelegateStmt(delegateTypeName, methodSymbol.Name, "value"))
+                        SF.ParseStatement(StubbingUtils.GenerateInvokeDelegateStmt(delegateTypeName, setMethodSymbol.Name, parameters))
                     })));
+                if (propDclr == null)
+                {
+                    propDclr = CreatePropertyDclr(setMethodSymbol, indexerType);
+                }
                 propDclr = propDclr.AddAccessorListAccessors(accessorDclr);
             }
 
-            if (propDclr != null)
-            {
-                PropertyDeclarationSyntax existingPropDclr = GetPropDclr(classDclr, propName);
-                if (existingPropDclr != null)
-                {
-                    classDclr = classDclr.ReplaceNode(existingPropDclr, propDclr);
-                }
-                else
-                {
             classDclr = classDclr.AddMembers(propDclr);
-                }
-            }
-
             return classDclr;
         }
 
-        private static PropertyDeclarationSyntax GetPropDclr(ClassDeclarationSyntax classDclr, string propName)
+        private BasePropertyDeclarationSyntax CreatePropertyDclr(IMethodSymbol methodSymbol, string propType)
         {
-            return
-                classDclr.DescendantNodes()
-                    .OfType<PropertyDeclarationSyntax>()
-                    .FirstOrDefault(p => p.Identifier.Text == propName);
+            if (methodSymbol.IsIndexerAccessor())
+            {
+                IndexerDeclarationSyntax indexerDclr = SF.IndexerDeclaration(
+                    SF.ParseTypeName(propType))
+                    .WithExplicitInterfaceSpecifier(SF.ExplicitInterfaceSpecifier(
+                        SF.IdentifierName(methodSymbol.GetContainingInterfaceGenericQualifiedName())));
+                indexerDclr = indexerDclr.AddParameterListParameters(
+                        RoslynUtils.GetMethodParameterSyntaxList(methodSymbol).ToArray());
+                return indexerDclr;
+            }
+
+            string propName = methodSymbol.AssociatedSymbol.Name;
+            PropertyDeclarationSyntax propDclr = SF.PropertyDeclaration(SF.ParseTypeName(propType), SF.Identifier(propName))
+            .WithExplicitInterfaceSpecifier(SF.ExplicitInterfaceSpecifier(
+                SF.IdentifierName(methodSymbol.GetContainingInterfaceGenericQualifiedName())));
+            return propDclr;
         }
     }
 }

src/SimpleStubs.CodeGen/DI/DIModule.cs

@@ -30,8 +30,11 @@ namespace Etg.SimpleStubs.CodeGen.DI
                     {
                         new OrdinaryMethodStubber(),
                         new EventStubber(),
-                        new PropertyStubber(),
                         new StubbingDelegateGenerator()
+                    },
+                    new IPropertyStubber[]
+                    {
+                        new PropertyStubber()
                     });
                 return interfaceStubber;
             }).As<IInterfaceStubber>().SingleInstance();

src/SimpleStubs.CodeGen/SimpleStubs.CodeGen.csproj

@@ -102,6 +102,7 @@
     <Compile Include="CodeGen\IInterfaceStubber.cs" />
     <Compile Include="CodeGen\InterfaceStubber.cs" />
     <Compile Include="CodeGen\IProjectStubber.cs" />
+    <Compile Include="CodeGen\IPropertyStubber.cs" />
     <Compile Include="CodeGen\ProjectStubber.cs" />
     <Compile Include="Utils\StubbingUtils.cs" />
     <Compile Include="CodeGen\StubProjectResult.cs" />

src/SimpleStubs.CodeGen/Utils/NamingUtils.cs

@@ -42,7 +42,7 @@ namespace Etg.SimpleStubs.CodeGen.Utils
 				methodName = SerializeName(methodSymbol.ContainingSymbol) + "_" + methodName;
 			}
 
-			if (methodSymbol.IsOrdinaryMethod())
+			if (methodSymbol.IsOrdinaryMethod() || methodSymbol.IsIndexerAccessor())
 			{
 				if (methodSymbol.Parameters.Any())
 				{

src/SimpleStubs.CodeGen/Utils/RoslynExtensions.cs

@@ -42,6 +42,22 @@ namespace Etg.SimpleStubs.CodeGen.Utils
             return methodSymbol.MethodKind == MethodKind.PropertyGet;
         }
 
+        public static bool IsIndexerGetter(this IMethodSymbol methodSymbol)
+        {
+            return methodSymbol.Name == "get_Item";
+        }
+
+        public static bool IsIndexerSetter(this IMethodSymbol methodSymbol)
+        {
+            return methodSymbol.Name == "set_Item";
+        }
+
+        public static bool IsIndexerAccessor(this IMethodSymbol methodSymbol)
+        {
+            IPropertySymbol propertySymbol = methodSymbol.AssociatedSymbol as IPropertySymbol;
+            return propertySymbol != null && propertySymbol.IsIndexer;
+        }
+
         public static string GetGenericName(this IMethodSymbol methodSymbol)
         {
             string name = methodSymbol.Name;
@@ -52,7 +68,7 @@ namespace Etg.SimpleStubs.CodeGen.Utils
             return name;
         }
 
-        public static string GetContainingInterfaceGenericQualifiedName(this IMethodSymbol methodSymbol)
+        public static string GetContainingInterfaceGenericQualifiedName(this ISymbol methodSymbol)
         {
             return methodSymbol.ContainingSymbol.ToDisplayString(SymbolDisplayFormat.FullyQualifiedFormat);
         }
@@ -102,5 +118,21 @@ namespace Etg.SimpleStubs.CodeGen.Utils
             };
             return !typeDclr.Modifiers.Any(modifier => nonInternalModifiers.Contains(modifier.RawKind));
         }
+
+        public static BasePropertyDeclarationSyntax AddAccessorListAccessors(this BasePropertyDeclarationSyntax baseDclr, params AccessorDeclarationSyntax[] accessors)
+        {
+            var propDclr = baseDclr as PropertyDeclarationSyntax;
+            if (propDclr != null)
+            {
+                return propDclr.AddAccessorListAccessors(accessors);
+            }
+
+            var indexerDclr = baseDclr as IndexerDeclarationSyntax;
+            if (indexerDclr != null)
+            {
+                return indexerDclr.AddAccessorListAccessors(accessors); 
+            }
+            throw new InvalidOperationException();
+        }
     }
 }

src/SimpleStubs.CodeGen/Utils/RoslynUtils.cs

@@ -55,21 +55,21 @@ namespace Etg.SimpleStubs.CodeGen.Utils
             return paramsSyntaxList;
         }
 
-        public static List<IMethodSymbol> GetAllMethods(INamedTypeSymbol interfaceType)
+        public static List<T> GetAllMembers<T>(INamedTypeSymbol interfaceType)
         {
-            var methodsToStub = new List<IMethodSymbol>(interfaceType.GetMembers().OfType<IMethodSymbol>());
-            methodsToStub.AddRange(GetAllInheritedMethods(interfaceType));
+            var methodsToStub = new List<T>(interfaceType.GetMembers().OfType<T>());
+            methodsToStub.AddRange(GetAllInheritedMethods<T>(interfaceType));
             return methodsToStub;
         }
 
-        public static IEnumerable<IMethodSymbol> GetAllInheritedMethods(ITypeSymbol typeSymbol)
+        public static IEnumerable<T> GetAllInheritedMethods<T>(ITypeSymbol typeSymbol)
         {
-            var methods = new List<IMethodSymbol>();
+            var methods = new List<T>();
             if (typeSymbol.AllInterfaces.Any())
             {
                 foreach (var baseInterfaceType in typeSymbol.AllInterfaces)
                 {
-                    methods.AddRange(baseInterfaceType.GetMembers().OfType<IMethodSymbol>());
+                    methods.AddRange(baseInterfaceType.GetMembers().OfType<T>());
                 }
             }
 

src/SimpleStubs.CodeGen/Utils/StubbingUtils.cs

@@ -9,5 +9,21 @@ namespace Etg.SimpleStubs.CodeGen.Utils
         {
             return $"_stubs.GetMethodStub<{delegateTypeName}>(\"{methodName}\").Invoke({parameters});\n";
         }
+
+        public static string FormatParameters(IMethodSymbol methodSymbol)
+        {
+            return string.Join(", ", methodSymbol.Parameters.Select(p =>
+            {
+                if (p.RefKind == RefKind.Out)
+                {
+                    return $"out {p.Name}";
+                }
+                if (p.RefKind == RefKind.Ref)
+                {
+                    return $"ref {p.Name}";
+                }
+                return p.Name;
+            }));
+        }
     }
 }

test/TestClassLibrary/ITestInterface.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Security.Cryptography.X509Certificates;
 using System.Threading.Tasks;
 
 namespace TestClassLibrary
@@ -20,12 +21,18 @@ namespace TestClassLibrary
         event EventHandler<long> PhoneNumberChanged;
     }
 
+    // just to make sure all inherited members are stubbed
+    public interface IPhoneBookSpecial : IPhoneBook
+    {
+    }
+
     public interface IContainer
     {
         T GetElement<T>(int index);
         void SetElement<T>(int index, T value);
 
         bool GetElement(int index, out object value);
+
     }
 
     public interface IRefUtils
@@ -74,6 +81,18 @@ namespace TestClassLibrary
         T GetX();
     }
 
+    public interface IGenericContainer<T>
+    {
+        T this[int index] { get; set; }
+
+        T this[string key, int n] { get; }
+    }
+
+    // just to make sure inherited indexers are stubbed
+    public interface IGenericContainerSubInterface : IGenericContainer<int>
+    {
+    }
+
     public interface IInterfaceWithGenericMethod
     {
         T GetFoo<T>() where T : class;

test/TestClassLibraryTest/UnitTest.cs

@@ -115,7 +115,7 @@ namespace TestClassLibraryTest
         public void TestThatMethodStubCanBeOverwritten()
         {
             var stub = new StubIPhoneBook().GetContactPhoneNumber((p1, p2) => 12345678);
-            stub.GetContactPhoneNumber((p1, p2) => 11122233, overwrite:true);
+            stub.GetContactPhoneNumber((p1, p2) => 11122233, overwrite: true);
 
             IPhoneBook phoneBook = stub;
             Assert.AreEqual(11122233, phoneBook.GetContactPhoneNumber("John", "Smith"));
@@ -165,12 +165,63 @@ namespace TestClassLibraryTest
             int i1 = 1;
             int i2 = 2;
 
-            ((IRefUtils) stub).Swap<int>(ref i1, ref i2);
+            ((IRefUtils)stub).Swap<int>(ref i1, ref i2);
             Assert.AreEqual(2, i1);
             Assert.AreEqual(1, i2);
         }
 
+        [TestMethod]
+        public void TestIndexerGet()
+        {
+            var stub = new StubIGenericContainer<int>();
+            stub.Item_Get(index =>
+            {
+                switch (index)
+                {
+                    case 0:
+                        return 13;
+                    case 1:
+                        return 5;
+                    default:
+                        throw new IndexOutOfRangeException();
+                }
+            });
+
+            IGenericContainer<int> container = stub;
+            Assert.AreEqual(13, container[0]);
+            Assert.AreEqual(5, container[1]);
+        }
+
+        [TestMethod]
+        public void TestIndexerSet()
+        {
+            var stub = new StubIGenericContainer<int>();
+            int res = -1;
+            stub.Item_Set((index, value) =>
+            {
+                if (index != 0) throw new IndexOutOfRangeException();
+                res = value;
+            });
+
+            IGenericContainer<int> container = stub;
+            container[0] = 13;
+
+            Assert.AreEqual(13, res);
+        }
+
+        [TestMethod]
+        public void TestThatMultipleIndexerDontConflict()
+        {
+            var stub = new StubIGenericContainer<int>();
+            stub.Item_Get(index => 12).Item_Get((key, i) => 3);
+
+            IGenericContainer<int> container = stub;
+            Assert.AreEqual(12, container[0]);
+            Assert.AreEqual(3, container["foo", 0]);
+        }
+
         // this test is only used for debugging
+        [Ignore]
         [TestMethod]
         public async Task TestGenerateStubs()
         {