New Rule T0017: Use short name for common types

analyzers/src/SonarAnalyzer.CSharp.Styling/Rules/UseShortName.cs

@@ -0,0 +1,78 @@
+/*
+ * SonarAnalyzer for .NET
+ * Copyright (C) 2015-2024 SonarSource SA
+ * mailto: contact AT sonarsource DOT com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+namespace SonarAnalyzer.Rules.CSharp.Styling;
+
+[DiagnosticAnalyzer(LanguageNames.CSharp)]
+public sealed class UseShortName : StylingAnalyzer
+{
+    private static readonly RenameInfo[] RenameCandidates =
+        [
+            new("CancellationToken", "cancellationToken", "cancel"),
+            new("CancellationToken", "CancellationToken", "Cancel"),
+            new("DiagnosticDescriptor", "diagnosticDescriptor", "descriptor"),
+            new("DiagnosticDescriptor", "DiagnosticDescriptor", "Descriptor"),
+            new("SyntaxNode", "syntaxNode", "node"),
+            new("SyntaxNode", "SyntaxNode", "Node"),
+            new("SyntaxToken", "syntaxToken", "token"),
+            new("SyntaxToken", "SyntaxToken", "Token"),
+            new("SyntaxTree", "syntaxTree", "tree"),
+            new("SyntaxTree", "SyntaxTree", "Tree"),
+            new("SyntaxTrivia", "syntaxTrivia", "trivia"),
+            new("SyntaxTrivia", "SyntaxTrivia", "Trivia"),
+            new("SemanticModel", "semanticModel", "model"),
+            new("SemanticModel", "SemanticModel", "Model")
+        ];
+
+    public UseShortName() : base("T0017", "Use short name '{0}'.") { }
+
+    protected override void Initialize(SonarAnalysisContext context)
+    {
+        context.RegisterNodeAction(c => ValidateDeclaration(c, ((VariableDeclaratorSyntax)c.Node).Identifier), SyntaxKind.VariableDeclarator);
+        context.RegisterNodeAction(c => ValidateDeclaration(c, ((PropertyDeclarationSyntax)c.Node).Identifier), SyntaxKind.PropertyDeclaration);
+        context.RegisterNodeAction(c =>
+            {
+                if (!FollowsPredefinedName(c.ContainingSymbol))
+                {
+                    ValidateDeclaration(c, ((ParameterSyntax)c.Node).Identifier);
+                }
+            },
+            SyntaxKind.Parameter);
+    }
+
+    private void ValidateDeclaration(SonarSyntaxNodeReportingContext context, SyntaxToken identifier)
+    {
+        if (FindRename(identifier.ValueText) is { } name
+            && context.SemanticModel.GetDeclaredSymbol(context.Node).GetSymbolType() is { } type
+            && type.Name == name.TypeName)
+        {
+            context.ReportIssue(Rule, identifier, identifier.ValueText.Replace(name.UsedName, name.SuggestedName));
+        }
+    }
+
+    private static RenameInfo FindRename(string name) =>
+        Array.Find(RenameCandidates, x => name.Contains(x.UsedName));
+
+    private static bool FollowsPredefinedName(ISymbol symbol) =>
+        symbol is IMethodSymbol method
+        && (symbol.IsOverride || symbol.GetInterfaceMember() is not null || method.PartialDefinitionPart is not null);
+
+    private sealed record RenameInfo(string TypeName, string UsedName, string SuggestedName);
+}

analyzers/src/SonarAnalyzer.Common/Helpers/SymbolHelper.cs

@@ -22,7 +22,7 @@
 
 namespace SonarAnalyzer.Helpers
 {
-    internal static class SymbolHelper
+    public static class SymbolHelper
     {
         private static readonly PropertyInfo ITypeSymbolIsRecord = typeof(ITypeSymbol).GetProperty("IsRecord");
 

analyzers/src/SonarAnalyzer.Common/Helpers/TypeHelper.cs

@@ -23,7 +23,7 @@
 
 namespace SonarAnalyzer.Helpers;
 
-internal static class TypeHelper
+public static class TypeHelper
 {
     #region TypeKind
 

analyzers/tests/SonarAnalyzer.CSharp.Styling.Test/Rules/UseShortNameTest.cs

@@ -0,0 +1,29 @@
+/*
+ * SonarAnalyzer for .NET
+ * Copyright (C) 2015-2024 SonarSource SA
+ * mailto: contact AT sonarsource DOT com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+namespace SonarAnalyzer.CSharp.Styling.Test.Rules;
+
+[TestClass]
+public class UseShortNameTest
+{
+    [TestMethod]
+    public void UseShortName() =>
+        StylingVerifierBuilder.Create<UseShortName>().AddPaths("UseShortName.cs").Verify();
+}

analyzers/tests/SonarAnalyzer.CSharp.Styling.Test/TestCases/UseShortName.cs

@@ -0,0 +1,147 @@
+using System.Threading;
+
+public class Sample
+{
+    public void SuggestedNames(SyntaxNode node, SyntaxTree tree, SemanticModel model, CancellationToken cancel) { }
+    public void OtherNames(SyntaxNode song, SyntaxTree wood, SemanticModel sculpture, CancellationToken nuke) { }
+
+    public void LongName1(SyntaxNode syntaxNode) { }     // Noncompliant {{Use short name 'node'.}}
+    //                               ^^^^^^^^^^
+    public void LongName2(SyntaxNode prefixedSyntaxNode) { }         // Noncompliant {{Use short name 'prefixedNode'.}}
+    public void LongName3(SyntaxNode syntaxNodeCount) { }            // Noncompliant {{Use short name 'nodeCount'.}}
+    public void LongName4(SyntaxTree syntaxTree) { }                 // Noncompliant {{Use short name 'tree'.}}
+    public void LongName5(SyntaxTree firstSyntaxTreeCount) { }       // Noncompliant {{Use short name 'firstTreeCount'.}}
+    public void LongName6(CancellationToken cancellationToken) { }   // Noncompliant {{Use short name 'cancel'.}}
+
+    private SyntaxNode node;
+    private SyntaxNode otherNode, syntaxNode;   // Noncompliant {{Use short name 'node'.}}
+    //                            ^^^^^^^^^^
+    private SyntaxTree syntaxTree;              // Noncompliant
+    private SemanticModel semanticModel;        // Noncompliant
+
+    public SyntaxNode SyntaxNode { get; }       // Noncompliant {{Use short name 'Node'.}}
+    //                ^^^^^^^^^^
+
+    private SyntaxToken syntaxToken;            // Noncompliant {{Use short name 'token'.}}
+    private SyntaxToken SyntaxToken { get; }    // Noncompliant {{Use short name 'Token'.}}
+
+    private SyntaxTrivia syntaxTrivia;          // Noncompliant {{Use short name 'trivia'.}}
+    private SyntaxTrivia SyntaxTrivia{ get; }   // Noncompliant {{Use short name 'Trivia'.}}
+
+    private DiagnosticDescriptor diagnosticDescriptor;          // Noncompliant {{Use short name 'descriptor'.}}
+    private DiagnosticDescriptor DiagnosticDescriptor { get; }  // Noncompliant {{Use short name 'Descriptor'.}}
+
+    public void TypedDeclarations()
+    {
+        SyntaxNode nodeNode;
+        SyntaxNode otherNode;
+        SyntaxNode node;
+        SyntaxNode syntaxNode;  // Noncompliant {{Use short name 'node'.}} If there exist 'node' and 'syntaxNode' in the same scope, both need a rename.
+
+        SyntaxTree syntaxTree;                  // Noncompliant
+        SemanticModel semanticModel;            // Noncompliant
+        CancellationToken cancellationToken;    // Noncompliant
+
+        void SyntaxNode() { }   // Not in the scope (for now)
+    }
+
+    public void VarDeclarations()
+    {
+        var nodeNode = CreateNode();
+        var otherNode = CreateNode();
+        var node = CreateNode();
+        var syntaxNode = CreateNode();  // Noncompliant {{Use short name 'node'.}} If there exist 'node' and 'syntaxNode' in the same scope, both need a rename.
+        //  ^^^^^^^^^^
+
+        var syntaxTree = CreateTree();          // Noncompliant
+        var semanticModel = CreateModel();      // Noncompliant
+        var cancellationToken = CreateCancel(); // Noncompliant
+
+        void SyntaxNode() { }   // Not in the scope (for now)
+    }
+
+    public void UnexpectedType(SyntaxNode syntaxTree)   // Wrong, but compliant
+    {
+        var semanticModel = CreateNode();               // Wrong, but compliant
+        SemanticModel syntaxNode = null;                // Wrong, but compliant
+    }
+
+    private SyntaxNode CreateNode() => null;
+    private SyntaxTree CreateTree() => null;
+    private SemanticModel CreateModel() => null;
+    private CancellationToken CreateCancel() => default;
+
+    private class NestedWithPublicFields
+    {
+        public SyntaxNode SyntaxNode;       // Noncompliant {{Use short name 'Node'.}}
+        public SyntaxTree SyntaxTree;       // Noncompliant
+        public SemanticModel SemanticModel; // Noncompliant
+    }
+}
+
+public class ArrowProperty
+{
+    public SyntaxNode SyntaxNode => null;   // Noncompliant
+}
+
+public class BodyProperty
+{
+    public SyntaxNode SyntaxNode            // Noncompliant
+    {
+        get => null;
+        set { }
+    }
+}
+
+public class Methods
+{
+    // It does not appy to method names
+    public void SyntaxNode() { }
+    public void SyntaxTree() { }
+    public void SemanticModel() { }
+    public void CancellationToken() { }
+}
+
+public abstract class Base
+{
+    protected abstract void DoSomething(SyntaxNode syntaxNode); // Noncompliant {{Use short name 'node'.}}
+}
+
+public class Inherited : Base
+{
+    protected override void DoSomething(SyntaxNode syntaxNode) // Compliant so we don't contradict S927
+    {
+    }
+}
+
+public interface IInterface
+{
+    void DoSomething(SyntaxNode syntaxNode);    // Noncompliant
+}
+
+public class Implemented : IInterface
+{
+    public void DoSomething(SyntaxNode syntaxNode) // Compliant so we don't contradict S927
+    {
+    }
+}
+
+public partial class Partial
+{
+    public partial void DoSomething(SyntaxNode syntaxNode); // Noncompliant
+}
+
+public partial class Partial
+{
+    public partial void DoSomething(SyntaxNode syntaxNode) // Compliant so we don't contradict S927
+    {
+        // Implementation
+    }
+}
+
+public class SyntaxNode { }
+public class SyntaxToken { }
+public class SyntaxTree { }
+public class SyntaxTrivia { }
+public class SemanticModel { }
+public class DiagnosticDescriptor { }