Add support for file scoped namespace to SA1516.

Author: JakubLinhart

StyleCop.Analyzers/StyleCop.Analyzers.Test.CSharp10/LayoutRules/SA1516CSharp10UnitTests.cs

@@ -3,9 +3,137 @@
 
 namespace StyleCop.Analyzers.Test.CSharp10.LayoutRules
 {
+    using System.Threading;
+    using System.Threading.Tasks;
+    using Microsoft.CodeAnalysis;
+    using Microsoft.CodeAnalysis.CSharp;
+    using Microsoft.CodeAnalysis.Testing;
     using StyleCop.Analyzers.Test.CSharp9.LayoutRules;
+    using Xunit;
+    using static StyleCop.Analyzers.Test.Verifiers.StyleCopCodeFixVerifier<
+        StyleCop.Analyzers.LayoutRules.SA1516ElementsMustBeSeparatedByBlankLine,
+        StyleCop.Analyzers.LayoutRules.SA1516CodeFixProvider>;
 
     public class SA1516CSharp10UnitTests : SA1516CSharp9UnitTests
     {
+        private const string CorrectCode = @"extern alias corlib;
+
+using System;
+using System.Linq;
+using a = System.Collections.Generic;
+
+namespace Foo;
+
+public class Bar
+{
+    public string Test1;
+    public string Test2;
+    public string Test3;
+
+    public string TestProperty1 { get; set; }
+
+    public string TestProperty2 { get; set; }
+    /// <summary>
+    /// A summary.
+    /// </summary>
+    public string TestProperty3 { get; set; }
+
+    public string TestProperty4
+    {
+        get
+        {
+            return Test1;
+        }
+
+        set
+        {
+            Test1 = value;
+        }
+    }
+
+    public string FooValue, BarValue;
+
+    [Obsolete]
+    public enum TestEnum
+    {
+        Value1,
+        Value2
+    }
+}
+
+public enum Foobar
+{
+
+}
+";
+
+        /// <summary>
+        /// Verifies that SA1516 is not reported for code with correct blank lines.
+        /// </summary>
+        /// <returns>A <see cref="Task"/> representing the asynchronous unit test.</returns>
+        [Fact]
+        [WorkItem(3512, "https://github.com/DotNetAnalyzers/StyleCopAnalyzers/issues/3512")]
+        public async Task TestFileScopedNamespaceCorrectSpacingAsync()
+        {
+            await VerifyCSharpDiagnosticAsync(CorrectCode, DiagnosticResult.EmptyDiagnosticResults, CancellationToken.None).ConfigureAwait(false);
+        }
+
+        /// <summary>
+        /// Verifies that SA1516 is reported for code with missing correct blank lines.
+        /// </summary>
+        /// <returns>A <see cref="Task"/> representing the asynchronous unit test.</returns>
+        [Fact]
+        [WorkItem(3512, "https://github.com/DotNetAnalyzers/StyleCopAnalyzers/issues/3512")]
+        public async Task TestFileScopedNamespaceWrongSpacingAsync()
+        {
+            var testCode = @"extern alias corlib;
+{|#0:using|} System;
+using System.Linq;
+using a = System.Collections.Generic;
+{|#1:namespace|} Foo;
+{|#2:public|} class Bar
+{
+}
+{|#3:public|} enum Foobar
+{
+}
+";
+
+            var fixedCode = @"extern alias corlib;
+
+using System;
+using System.Linq;
+using a = System.Collections.Generic;
+
+namespace Foo;
+
+public class Bar
+{
+}
+
+public enum Foobar
+{
+}
+";
+
+            var test = new CSharpTest(LanguageVersion.CSharp10)
+            {
+                ReferenceAssemblies = ReferenceAssemblies.Net.Net50,
+                TestState =
+                {
+                    OutputKind = OutputKind.DynamicallyLinkedLibrary,
+                    Sources = { testCode },
+                },
+                FixedCode = fixedCode,
+            };
+            var expectedDiagnostic = new[] {
+                Diagnostic().WithLocation(0),
+                Diagnostic().WithLocation(1),
+                Diagnostic().WithLocation(2),
+                Diagnostic().WithLocation(3),
+            };
+            test.TestState.ExpectedDiagnostics.AddRange(expectedDiagnostic);
+            await test.RunAsync(CancellationToken.None).ConfigureAwait(false);
+        }
     }
 }

StyleCop.Analyzers/StyleCop.Analyzers/LayoutRules/SA1516ElementsMustBeSeparatedByBlankLine.cs

@@ -15,6 +15,7 @@ namespace StyleCop.Analyzers.LayoutRules
     using Microsoft.CodeAnalysis.Diagnostics;
     using Microsoft.CodeAnalysis.Text;
     using StyleCop.Analyzers.Helpers;
+    using StyleCop.Analyzers.Lightup;
     using StyleCop.Analyzers.Settings.ObjectModel;
 
     /// <summary>
@@ -87,6 +88,7 @@ internal class SA1516ElementsMustBeSeparatedByBlankLine : DiagnosticAnalyzer
         private static readonly Action<SyntaxNodeAnalysisContext> TypeDeclarationAction = HandleTypeDeclaration;
         private static readonly Action<SyntaxNodeAnalysisContext, StyleCopSettings> CompilationUnitAction = HandleCompilationUnit;
         private static readonly Action<SyntaxNodeAnalysisContext, StyleCopSettings> NamespaceDeclarationAction = HandleNamespaceDeclaration;
+        private static readonly Action<SyntaxNodeAnalysisContext, StyleCopSettings> FileScopedNamespaceDeclarationAction = HandleFileScopedNamespaceDeclaration;
         private static readonly Action<SyntaxNodeAnalysisContext> BasePropertyDeclarationAction = HandleBasePropertyDeclaration;
 
         private static readonly ImmutableDictionary<string, string> DiagnosticProperties = ImmutableDictionary<string, string>.Empty.Add(CodeFixActionKey, InsertBlankLineValue);
@@ -127,6 +129,7 @@ public override void Initialize(AnalysisContext context)
             context.RegisterSyntaxNodeAction(TypeDeclarationAction, SyntaxKinds.TypeDeclaration);
             context.RegisterSyntaxNodeAction(CompilationUnitAction, SyntaxKind.CompilationUnit);
             context.RegisterSyntaxNodeAction(NamespaceDeclarationAction, SyntaxKind.NamespaceDeclaration);
+            context.RegisterSyntaxNodeAction(FileScopedNamespaceDeclarationAction, SyntaxKindEx.FileScopedNamespaceDeclaration);
             context.RegisterSyntaxNodeAction(BasePropertyDeclarationAction, SyntaxKinds.BasePropertyDeclaration);
         }
 
@@ -209,6 +212,20 @@ private static void HandleCompilationUnit(SyntaxNodeAnalysisContext context, Sty
             }
         }
 
+        private static void HandleFileScopedNamespaceDeclaration(SyntaxNodeAnalysisContext context, StyleCopSettings settings)
+        {
+            var namespaceDeclaration = (BaseNamespaceDeclarationSyntaxWrapper)context.Node;
+
+            var members = namespaceDeclaration.Members;
+
+            HandleMemberList(context, members);
+
+            if (members.Count > 0)
+            {
+                ReportIfThereIsNoBlankLine(context, namespaceDeclaration.Name, members[0]);
+            }
+        }
+
         private static void HandleNamespaceDeclaration(SyntaxNodeAnalysisContext context, StyleCopSettings settings)
         {
             var namespaceDeclaration = (NamespaceDeclarationSyntax)context.Node;