Add issue provider for missing StringComparison argument to string.StartsWith/EndsWith/IndexOf/LastIndexOf calls.

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

@@ -301,6 +301,7 @@
     <Compile Include="Refactoring\CodeIssues\ExpressionIsNeverOfProvidedTypeIssue.cs" />
     <Compile Include="Refactoring\CodeIssues\MethodNeverReturnsIssue.cs" />
     <Compile Include="Refactoring\CodeIssues\MethodOverloadHidesOptionalParameterIssue.cs" />
+    <Compile Include="Refactoring\CodeIssues\MissingStringComparisonIssue.cs" />
     <Compile Include="Refactoring\CodeIssues\NegativeRelationalExpressionIssue.cs" />
     <Compile Include="Refactoring\CodeIssues\ExplicitConversionInForEachIssue.cs" />
     <Compile Include="Refactoring\CodeIssues\ForControlVariableNotModifiedIssue.cs" />

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

@@ -0,0 +1,106 @@
+//
+// MissingStringComparisonIssue.cs
+//
+// Author:
+//       Daniel Grunwald <daniel@danielgrunwald.de>
+//
+// Copyright (c) 2012 Daniel Grunwald
+//
+// 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;
+using System.Collections.Generic;
+using System.Linq;
+using ICSharpCode.NRefactory.Semantics;
+using ICSharpCode.NRefactory.TypeSystem;
+using ICSharpCode.NRefactory.TypeSystem.Implementation;
+
+namespace ICSharpCode.NRefactory.CSharp.Refactoring
+{
+	[IssueDescription("Missing StringComparison argument",
+	                  Description = "Warns when a culture-aware comparison is used by default.",
+	                  Category = IssueCategories.CodeQualityIssues,
+	                  Severity = Severity.Warning)]
+	public class MissingStringComparisonIssue : ICodeIssueProvider
+	{
+		public IEnumerable<CodeIssue> GetIssues(BaseRefactoringContext context)
+		{
+			return new GatherVisitor(context).GetIssues();
+		}
+		
+		class GatherVisitor : GatherVisitorBase
+		{
+			public GatherVisitor(BaseRefactoringContext ctx) : base(ctx)
+			{
+			}
+			
+			public override void VisitInvocationExpression(InvocationExpression invocationExpression)
+			{
+				base.VisitInvocationExpression(invocationExpression);
+				
+				MemberReferenceExpression mre = invocationExpression.Target as MemberReferenceExpression;
+				if (mre == null)
+					return;
+				switch (mre.MemberName) {
+					case "StartsWith":
+					case "EndsWith":
+						if (invocationExpression.Arguments.Count != 1)
+							return;
+						break;
+					case "IndexOf":
+					case "LastIndexOf":
+						break;
+					default:
+						return;
+				}
+				
+				var rr = ctx.Resolve(invocationExpression) as InvocationResolveResult;
+				if (rr == null || rr.IsError) {
+					// Not an invocation resolve result - e.g. could be a UnknownMemberResolveResult instead
+					return;
+				}
+				if (!(rr.Member.DeclaringTypeDefinition != null && rr.Member.DeclaringTypeDefinition.KnownTypeCode == KnownTypeCode.String)) {
+					// Not a string operation
+					return;
+				}
+				IParameter firstParameter = rr.Member.Parameters.FirstOrDefault();
+				if (firstParameter == null || !firstParameter.Type.IsKnownType(KnownTypeCode.String))
+					return; // First parameter not a string
+				IParameter lastParameter = rr.Member.Parameters.Last();
+				if (lastParameter.Type.Name == "StringComparison")
+					return; // already specifying a string comparison
+				AddIssue(invocationExpression.LParToken.StartLocation, invocationExpression.RParToken.EndLocation,
+				         mre.MemberName + "() call is missing StringComparison argument",
+				         new [] {
+				         	new CodeAction("Use ordinal comparison", script => AddArgument(script, invocationExpression, "Ordinal")),
+				         	new CodeAction("Use culture-aware comparison", script => AddArgument(script, invocationExpression, "CurrentCulture")),
+				         });
+			}
+			
+			void AddArgument(Script script, InvocationExpression invocationExpression, string stringComparison)
+			{
+				var astBuilder = ctx.CreateTypeSytemAstBuilder(invocationExpression);
+				var newArgument = astBuilder.ConvertType(new TopLevelTypeName("System", "StringComparison")).Member(stringComparison);
+				var copy = (InvocationExpression)invocationExpression.Clone();
+				copy.Arguments.Add(newArgument);
+				script.Replace(invocationExpression, copy);
+			}
+		}
+	}
+}

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

@@ -32,7 +32,7 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 	{
 		public IEnumerable<CodeIssue> GetIssues(BaseRefactoringContext context)
 		{
-			return new GatherVisitor().GetIssues();
+			return new GatherVisitor(context).GetIssues();
 		}
 		
 		sealed class GatherVisitor : GatherVisitorBase

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

@@ -0,0 +1,93 @@
+//
+// Author:
+//       Daniel Grunwald <daniel@danielgrunwald.de>
+//
+// Copyright (c) 2012 Daniel Grunwald
+//
+// 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;
+using ICSharpCode.NRefactory.CSharp.Refactoring;
+using NUnit.Framework;
+
+namespace ICSharpCode.NRefactory.CSharp.CodeIssues
+{
+	[TestFixture]
+	public class MissingStringComparisonIssueTests : InspectionActionTestBase
+	{
+		const string stringIndexOfStringCalls = @"using System;
+using System.Collections.Generic;
+class Test {
+	public void StringIndexOfStringCalls(List<string> list)
+	{
+		list[0].IndexOf("".com"");
+		list[0].IndexOf("".com"", 0);
+		list[0].IndexOf("".com"", 0, 5);
+		list[0].IndexOf(list[1], 0, 10);
+	}
+}";
+		const string stringIndexOfStringCallsWithComparison = @"using System;
+using System.Collections.Generic;
+class Test {
+	public void StringIndexOfStringCalls(List<string> list)
+	{
+		list [0].IndexOf ("".com"", StringComparison.Ordinal);
+		list [0].IndexOf ("".com"", 0, StringComparison.Ordinal);
+		list [0].IndexOf ("".com"", 0, 5, StringComparison.Ordinal);
+		list [0].IndexOf (list [1], 0, 10, StringComparison.Ordinal);
+	}
+}";
+		
+		[Test]
+		public void IndexOfStringCalls()
+		{
+			Test<MissingStringComparisonIssue>(stringIndexOfStringCalls, 4, stringIndexOfStringCallsWithComparison);
+		}
+		
+		[Test]
+		public void IndexOfStringCallsAlreadyWithComparison()
+		{
+			Test<MissingStringComparisonIssue>(stringIndexOfStringCallsWithComparison, 0);
+		}
+		
+		[Test]
+		public void StringIndexOfChar()
+		{
+			string program = @"using System;
+class Test {
+	void M(string text) {
+		text.IndexOf('.');
+	}
+}";
+			Test<MissingStringComparisonIssue>(program, 0);
+		}
+		
+		[Test]
+		public void ListIndexOf()
+		{
+			string program = @"using System.Collections.Generic;
+class Test {
+	void M(List<string> list) {
+		list.IndexOf("".com"");
+	}
+}";
+			Test<MissingStringComparisonIssue>(program, 0);
+		}
+	}
+}

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

@@ -112,6 +112,7 @@
     <Compile Include="CSharp\CodeIssues\LocalVariableNotUsedIssueTests.cs" />
     <Compile Include="CSharp\CodeIssues\MethodNeverReturnsIssueTests.cs" />
     <Compile Include="CSharp\CodeIssues\MethodOverloadHidesOptionalParameterIssueTests.cs" />
+    <Compile Include="CSharp\CodeIssues\MissingStringComparisonIssueTests.cs" />
     <Compile Include="CSharp\CodeIssues\MultipleEnumerationIssueTests.cs" />
     <Compile Include="CSharp\CodeIssues\NegativeRelationalExpressionIssueTests.cs" />
     <Compile Include="CSharp\CodeIssues\ParameterHidesMemberIssueTests.cs" />