Fixes bug #10728 (Auto-Fix regarding control flow: "Convert to correct type")

ICSharpCode.NRefactory.CSharp/ICSharpCode.NRefactory.CSharp.csproj

@@ -301,6 +301,7 @@
     <Compile Include="Refactoring\CodeIssues\DoubleNegationIssue.cs" />
     <Compile Include="Refactoring\CodeIssues\ExpressionIsAlwaysOfProvidedTypeIssue.cs" />
     <Compile Include="Refactoring\CodeIssues\ExpressionIsNeverOfProvidedTypeIssue.cs" />
+    <Compile Include="Refactoring\CodeIssues\ExpressionOfCompatibleTypeCastIssue.cs" />
     <Compile Include="Refactoring\CodeIssues\MethodNeverReturnsIssue.cs" />
     <Compile Include="Refactoring\CodeIssues\MethodOverloadHidesOptionalParameterIssue.cs" />
     <Compile Include="Refactoring\CodeIssues\MissingStringComparisonIssue.cs" />

ICSharpCode.NRefactory.CSharp/Refactoring/CodeIssues/ExpressionOfCompatibleTypeCastIssue.cs

@@ -0,0 +1,89 @@
+// 
+// ExpressionOfCompatibleTypeCastIssue.cs
+// 
+// Author:
+//      Ciprian Khlud <ciprian.mustiata@yahoo.com>
+// 
+// Copyright (c) 2013 Ciprian Khlud <ciprian.mustiata@yahoo.com>
+// 
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+using System.Collections.Generic;
+using ICSharpCode.NRefactory.CSharp.Resolver;
+using ICSharpCode.NRefactory.Semantics;
+using ICSharpCode.NRefactory.TypeSystem;
+
+namespace ICSharpCode.NRefactory.CSharp.Refactoring
+{
+    [IssueDescription("Type cast expression of compatible type",
+        Description = "Type cast expression of compatible type",
+        Category = IssueCategories.CodeQualityIssues,
+        Severity = Severity.Warning,
+        IssueMarker = IssueMarker.Underline)]
+    public class ExpressionOfCompatibleTypeCastIssue : ICodeIssueProvider
+    {
+        public IEnumerable<CodeIssue> GetIssues(BaseRefactoringContext context)
+        {
+            return new GatherVisitor(context).GetIssues();
+        }
+
+        class GatherVisitor : GatherVisitorBase<CastExpressionOfIncompatibleTypeIssue>
+        {
+            readonly CSharpConversions conversion;
+
+            public GatherVisitor(BaseRefactoringContext ctx)
+                : base(ctx)
+            {
+                conversion = new CSharpConversions(ctx.Compilation);
+            }
+            public override void VisitAssignmentExpression(AssignmentExpression assignmentExpression)
+            {
+                base.VisitAssignmentExpression(assignmentExpression);
+
+                VisitTypeCastExpression(assignmentExpression, ctx.Resolve(assignmentExpression.Left).Type,
+                                        ctx.Resolve(assignmentExpression.Right).Type);
+            }
+
+            private AstType CreateShortType(AstNode node, IType fullType)
+            {
+                var builder = ctx.CreateTypeSytemAstBuilder(node);
+                return builder.ConvertType(fullType);
+            }
+		
+            void VisitTypeCastExpression(AssignmentExpression expression, IType exprType, IType castToType)
+            {
+                if (exprType.Kind == TypeKind.Unknown || castToType.Kind == TypeKind.Unknown)
+                    return;
+                var foundConversion = conversion.ExplicitConversion(exprType, castToType);
+                if (foundConversion == Conversion.None)
+                    return;
+                if (!foundConversion.IsExplicit)
+                    return;
+
+                AddIssue(expression, string.Format(ctx.TranslateString("Cast to '{0}'"),castToType.Name),
+                    script =>
+                    {
+                        var right = expression.Right.Clone();
+                        var castRight = right.CastTo(CreateShortType(expression, castToType));
+                        script.Replace(expression.Right, castRight);
+                    });
+            }
+        }
+    }
+}

ICSharpCode.NRefactory.Tests/CSharp/CodeIssues/ExpressionOfCompatibleTypeCastIssueTests.cs

@@ -0,0 +1,63 @@
+using ICSharpCode.NRefactory.CSharp.Refactoring;
+using NUnit.Framework;
+
+namespace ICSharpCode.NRefactory.CSharp.CodeIssues
+{
+    [TestFixture]
+    public class ExpressionOfCompatibleTypeCastIssueTests : InspectionActionTestBase
+    {
+        [Test]
+        public void TestConversion()
+        {
+            var input = @"
+class TestClass
+{
+enum Enum{ };
+	void TestMethod (Enum i)
+	{
+		int x;
+        x = i;
+	}
+}";
+            var output = @"
+class TestClass
+{
+enum Enum{ };
+	void TestMethod (Enum i)
+	{
+		int x;
+        x = (Enum)i;
+	}
+}";
+            Test<ExpressionOfCompatibleTypeIssueCast>(input, output);
+        }
+        [Test]
+        public void TestClassConversion()
+        {
+            var input = @"
+class Base {}
+class Test: Base {}
+class TestClass
+{
+	void TestMethod (Test i)
+	{
+		Base x;
+        x = i;
+	}
+}";
+            var output = @"
+class Base {}
+class Test: Base {}
+class TestClass
+{
+	void TestMethod (Test i)
+	{
+		Base x;
+        x = (Test)i;
+	}
+}";
+            Test<ExpressionOfCompatibleTypeIssueCast>(input, output);
+        }
+
+    }
+}

ICSharpCode.NRefactory.Tests/ICSharpCode.NRefactory.Tests.csproj

@@ -131,6 +131,7 @@
     <Compile Include="CSharp\CodeIssues\ExplicitConversionInForEachIssueTests.cs" />
     <Compile Include="CSharp\CodeIssues\ExpressionIsAlwaysOfProvidedTypeIssueTests.cs" />
     <Compile Include="CSharp\CodeIssues\ExpressionIsNeverOfProvidedTypeIssueTests.cs" />
+    <Compile Include="CSharp\CodeIssues\ExpressionOfCompatibleTypeIssueCastTests.cs" />
     <Compile Include="CSharp\CodeIssues\ForControlVariableNotModifiedIssueTests.cs" />
     <Compile Include="CSharp\CodeIssues\IdenticalConditionalBranchIssueTests.cs" />
     <Compile Include="CSharp\CodeIssues\LocalVariableHidesMemberIssueTests.cs" />