ILSpy/ICSharpCode.NRefactory.CSharp/Refactoring/CodeIssues/IdenticalConditionalBranchIssue.cs

// 
// IdenticalConditionalBranchIssue.cs
// 
// Author:
//      Mansheng Yang <lightyang0@gmail.com>
// 
// Copyright (c) 2012 Mansheng Yang <lightyang0@gmail.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.PatternMatching;

namespace ICSharpCode.NRefactory.CSharp.Refactoring
{

	[IssueDescription ("'?:' expression has identical true and false branches",
					   Description = "'?:' expression has identical true and false branches.",
					   Category = IssueCategories.CodeQualityIssues,
					   Severity = Severity.Warning,
					   IssueMarker = IssueMarker.Underline)]
	public class IdenticalConditionalBranchIssue : ICodeIssueProvider
	{
		public IEnumerable<CodeIssue> GetIssues (BaseRefactoringContext context)
		{
			return new GatherVisitor (context).GetIssues ();
		}

		class GatherVisitor : GatherVisitorBase
		{
			public GatherVisitor (BaseRefactoringContext ctx)
				: base (ctx)
			{
			}

			public override void VisitConditionalExpression (ConditionalExpression conditionalExpression)
			{
				base.VisitConditionalExpression (conditionalExpression);

				if (!conditionalExpression.TrueExpression.Match (conditionalExpression.FalseExpression).Success)
					return;
				var action = new CodeAction (ctx.TranslateString ("Replace '?:' with branch"),
					script => script.Replace (conditionalExpression, conditionalExpression.TrueExpression.Clone ()));
				AddIssue (conditionalExpression, 
					ctx.TranslateString ("'?:' expression has identical true and false branches"), new [] { action });
			}
		}
	}
}