Started inspection API.

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

@@ -322,6 +322,11 @@
     <Compile Include="Refactoring\ContextAction\RemoveRegion.cs" />
     <Compile Include="Refactoring\ContextAction\GenerateProperty.cs" />
     <Compile Include="Ast\Roles.cs" />
+    <Compile Include="Refactoring\Inspector\ConditionalToNullCoalescingInspector.cs" />
+    <Compile Include="Refactoring\IInspector.cs" />
+    <Compile Include="Refactoring\InspectionIssue.cs" />
+    <Compile Include="Refactoring\BaseRefactoringContext.cs" />
+    <Compile Include="Refactoring\Inspector\GatherVisitorBase.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\ICSharpCode.NRefactory\ICSharpCode.NRefactory.csproj">
@@ -332,6 +337,7 @@
   <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.Targets" />
   <ItemGroup>
     <Folder Include="Completion\" />
+    <Folder Include="Refactoring\Inspector\" />
   </ItemGroup>
   <ProjectExtensions>
     <MonoDevelop>

ICSharpCode.NRefactory.CSharp/Refactoring/BaseRefactoringContext.cs

@@ -0,0 +1,93 @@
+// 
+// BaseRefactoringContext.cs
+//  
+// Author:
+//       Mike Krüger <mkrueger@xamarin.com>
+// 
+// Copyright (c) 2012 Xamarin <http://xamarin.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;
+using System.Linq;
+using System.Threading;
+using ICSharpCode.NRefactory.CSharp.Resolver;
+using ICSharpCode.NRefactory.CSharp.TypeSystem;
+using ICSharpCode.NRefactory.Semantics;
+using ICSharpCode.NRefactory.TypeSystem;
+using ICSharpCode.NRefactory.TypeSystem.Implementation;
+using ICSharpCode.NRefactory.Editor;
+
+namespace ICSharpCode.NRefactory.CSharp.Refactoring
+{
+	public abstract class BaseRefactoringContext
+	{
+		protected readonly CSharpAstResolver resolver;
+		readonly CancellationToken cancellationToken;
+		
+		public virtual bool Supports(Version version)
+		{
+			return true;
+		}
+		
+		public CancellationToken CancellationToken {
+			get { return cancellationToken; }
+		}
+		
+		public virtual AstNode RootNode {
+			get { return resolver.RootNode; }
+		}
+
+		public ICompilation Compilation {
+			get { return resolver.Compilation; }
+		}
+
+		public BaseRefactoringContext (ICSharpCode.NRefactory.CSharp.Resolver.CSharpAstResolver resolver, System.Threading.CancellationToken cancellationToken)
+		{
+			this.resolver = resolver;
+			this.cancellationToken = cancellationToken;
+		}
+
+		#region Resolving
+		public ResolveResult Resolve (AstNode node)
+		{
+			return resolver.Resolve (node, cancellationToken);
+		}
+		
+		public IType ResolveType (AstType type)
+		{
+			return resolver.Resolve (type, cancellationToken).Type;
+		}
+		
+		public IType GetExpectedType (Expression expression)
+		{
+			return resolver.GetExpectedType(expression, cancellationToken);
+		}
+		
+		public Conversion GetConversion (Expression expression)
+		{
+			return resolver.GetConversion(expression, cancellationToken);
+		}
+		#endregion
+		
+		public abstract Script StartScript();
+
+	}
+	
+}

ICSharpCode.NRefactory.CSharp/Refactoring/IInspector.cs

@@ -0,0 +1,36 @@
+// 
+// IInspector.cs
+//  
+// Author:
+//       Mike Krüger <mkrueger@xamarin.com>
+// 
+// Copyright (c) 2012 Xamarin <http://xamarin.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;
+using System.Collections.Generic;
+
+namespace ICSharpCode.NRefactory.CSharp.Refactoring
+{
+	public interface IInspector
+	{
+		IEnumerable<InspectionIssue> Run (BaseRefactoringContext context);
+	}
+}
+

ICSharpCode.NRefactory.CSharp/Refactoring/InspectionIssue.cs

@@ -0,0 +1,61 @@
+// 
+// InspectionIssue.cs
+//  
+// Author:
+//       Mike Krüger <mkrueger@xamarin.com>
+// 
+// Copyright (c) 2012 Xamarin <http://xamarin.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;
+
+namespace ICSharpCode.NRefactory.CSharp.Refactoring
+{
+	public class InspectionIssue
+	{
+		public string Title {
+			get;
+			private set;
+		}
+		
+		public TextLocation Start {
+			get;
+			private set;
+		}
+		
+		public TextLocation End {
+			get;
+			private set;
+		}
+
+		public System.Action Fix {
+			get;
+			private set;
+		}
+
+		public InspectionIssue (string title, TextLocation start, TextLocation end, System.Action fix)
+		{
+			this.Title = title;
+			this.Start = start;
+			this.End = end;
+			this.Fix = fix;
+		}
+	}
+}
+

ICSharpCode.NRefactory.CSharp/Refactoring/Inspector/ConditionalToNullCoalescingInspector.cs

@@ -0,0 +1,131 @@
+// 
+// ConditionalToNullCoalescingInspector.cs
+//  
+// Author:
+//       Mike Krüger <mkrueger@xamarin.com>
+// 
+// Copyright (c) 2012 Xamarin <http://xamarin.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;
+using System.Collections.Generic;
+using ICSharpCode.NRefactory.PatternMatching;
+
+namespace ICSharpCode.NRefactory.CSharp.Refactoring
+{
+	/// <summary>
+	/// Checks for  obj != null ? obj : <expr> 
+	/// Converts to: obj ?? <expr>
+	/// </summary>
+	public class ConditionalToNullCoalescingInspector : IInspector
+	{
+		static ConditionalExpression[] Matches;
+
+		string title = "Convert to '??' expression";
+
+		public string Title {
+			get {
+				return title;
+			}
+			set {
+				title = value;
+			}
+		}		
+
+		public ConditionalToNullCoalescingInspector ()
+		{
+			Matches = new [] {
+				new ConditionalExpression (new BinaryOperatorExpression (new NullReferenceExpression (), BinaryOperatorType.Equality, new AnyNode ()), new AnyNode (), new AnyNode ()),
+				new ConditionalExpression (new BinaryOperatorExpression (new AnyNode (), BinaryOperatorType.Equality, new NullReferenceExpression ()), new AnyNode (), new AnyNode ()),
+				new ConditionalExpression (new BinaryOperatorExpression (new NullReferenceExpression (), BinaryOperatorType.InEquality, new AnyNode ()), new AnyNode (), new AnyNode ()),
+				new ConditionalExpression (new BinaryOperatorExpression (new AnyNode (), BinaryOperatorType.InEquality, new NullReferenceExpression ()), new AnyNode (), new AnyNode ()),
+			};
+		}
+
+		public IEnumerable<InspectionIssue> Run (BaseRefactoringContext context)
+		{
+			var visitor = new GatherVisitor (context, this);
+			context.RootNode.AcceptVisitor (visitor);
+			return visitor.FoundIssues;
+		}
+		
+		class GatherVisitor : GatherVisitorBase
+		{
+			readonly ConditionalToNullCoalescingInspector inspector;
+			
+			public GatherVisitor (BaseRefactoringContext ctx, ConditionalToNullCoalescingInspector inspector) : base (ctx)
+			{
+				this.inspector = inspector;
+			}
+
+			public override void VisitConditionalExpression (ConditionalExpression conditionalExpression)
+			{
+				foreach (var match in Matches) {
+					if (match.IsMatch (conditionalExpression) && IsCandidate (conditionalExpression)) {
+						AddIssue (conditionalExpression,
+						               inspector.Title,
+						               delegate {
+							using (var script = ctx.StartScript ()) {
+								var expressions = SortExpressions (conditionalExpression);
+								var expr = new BinaryOperatorExpression (expressions.Item1.Clone (), BinaryOperatorType.NullCoalescing, expressions.Item2.Clone ());
+								script.Replace (conditionalExpression, expr);
+							}
+						});
+					}
+				}
+				base.VisitConditionalExpression (conditionalExpression);
+			}
+		}
+
+		static bool IsCandidate (ConditionalExpression node)
+		{
+			var condition = node.Condition as BinaryOperatorExpression;
+			var compareNode = condition.Left is NullReferenceExpression ? condition.Right : condition.Left;
+			
+			
+			if (compareNode.IsMatch (node.TrueExpression)) {
+				// a == null ? a : other
+				if (condition.Operator == BinaryOperatorType.Equality) 
+					return false;
+				// a != null ? a : other
+				return compareNode.IsMatch (node.TrueExpression);
+			} else {
+				// a == null ? other : a
+				if (condition.Operator == BinaryOperatorType.Equality)
+					return compareNode.IsMatch (node.FalseExpression);
+				// a != null ? other : a
+				return false;
+			}
+		}
+
+		static Tuple<Expression, Expression> SortExpressions (ConditionalExpression cond)
+		{
+			var condition = cond.Condition as BinaryOperatorExpression;
+			var compareNode = condition.Left is NullReferenceExpression ? condition.Right : condition.Left;
+
+			if (compareNode.IsMatch (cond.TrueExpression)) {
+				// a != null ? a : other
+				return new Tuple<Expression, Expression> (cond.TrueExpression, cond.FalseExpression);
+			}
+
+			// a == null ? other : a
+			return new Tuple<Expression, Expression> (cond.FalseExpression, cond.TrueExpression);
+		}
+	}
+}

ICSharpCode.NRefactory.CSharp/Refactoring/Inspector/GatherVisitorBase.cs

@@ -0,0 +1,58 @@
+// 
+// GatherVisitorBase.cs
+//  
+// Author:
+//       Mike Krüger <mkrueger@xamarin.com>
+// 
+// Copyright (c) 2012 Xamarin <http://xamarin.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;
+using ICSharpCode.NRefactory.CSharp.Refactoring;
+using System.Collections.Generic;
+
+namespace ICSharpCode.NRefactory.CSharp
+{
+	class GatherVisitorBase : DepthFirstAstVisitor
+	{
+		protected readonly BaseRefactoringContext ctx;
+
+		public readonly List<InspectionIssue> FoundIssues = new List<InspectionIssue> ();
+
+		public GatherVisitorBase (BaseRefactoringContext ctx)
+		{
+			this.ctx = ctx;
+		}
+		
+		protected override void VisitChildren (AstNode node)
+		{
+			if (ctx.CancellationToken.IsCancellationRequested)
+				return;
+			base.VisitChildren (node);
+		}
+		
+		protected void AddIssue (AstNode node, string title, System.Action fix)
+		{
+			FoundIssues.Add (new InspectionIssue (title, node.StartLocation, node.EndLocation, fix));
+		}
+	}
+		
+	
+}
+

ICSharpCode.NRefactory.CSharp/Refactoring/RefactoringContext.cs

@@ -36,36 +36,14 @@ using ICSharpCode.NRefactory.Editor;
 
 namespace ICSharpCode.NRefactory.CSharp.Refactoring
 {
-	public abstract class RefactoringContext
+	public abstract class RefactoringContext : BaseRefactoringContext
 	{
-		readonly protected CSharpAstResolver resolver;
-		readonly CancellationToken cancellationToken;
-		
-		public RefactoringContext(CSharpAstResolver resolver, CancellationToken cancellationToken)
+		public RefactoringContext(CSharpAstResolver resolver, CancellationToken cancellationToken) : base  (resolver, cancellationToken)
 		{
-			this.resolver = resolver;
-			this.cancellationToken = cancellationToken;
-		}
-		
-		public CancellationToken CancellationToken {
-			get { return cancellationToken; }
-		}
-		
-		public virtual AstNode RootNode {
-			get { return resolver.RootNode; }
 		}
 
 		public abstract TextLocation Location { get; }
-		
-		public virtual bool Supports(Version version)
-		{
-			return true;
-		}
-		
-		public ICompilation Compilation {
-			get { return resolver.Compilation; }
-		}
-		
+
 		public virtual AstType CreateShortType (IType fullType)
 		{
 			var csResolver = resolver.GetResolverStateBefore(GetNode());
@@ -132,29 +110,7 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 
 		public abstract string GetText (ISegment segment);
 		#endregion
-		
-		#region Resolving
-		public ResolveResult Resolve (AstNode node)
-		{
-			return resolver.Resolve (node, cancellationToken);
-		}
-		
-		public IType ResolveType (AstType type)
-		{
-			return resolver.Resolve (type, cancellationToken).Type;
-		}
-		
-		public IType GetExpectedType (Expression expression)
-		{
-			return resolver.GetExpectedType(expression, cancellationToken);
-		}
-		
-		public Conversion GetConversion (Expression expression)
-		{
-			return resolver.GetConversion(expression, cancellationToken);
-		}
-		#endregion
-		
+
 		public virtual string GetNameProposal (string name, bool camelCase = true)
 		{
 			string baseName = (camelCase ? char.ToLower (name [0]) : char.ToUpper (name [0])) + name.Substring (1);
@@ -175,8 +131,6 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 		{
 			return baseName + (number > 0 ? (number + 1).ToString () : "");
 		}
-		
-		public abstract Script StartScript();
 	}
 }