Use collection expressions

src/Analyzers/CSharp/CodeFixes/ConvertNamespace/ConvertNamespaceTransform.cs

@@ -291,9 +291,9 @@ private static SyntaxNode ReplaceWithBlockScopedNamespace(
         }
 
         return document.Root.ReplaceSyntax(
-            new SyntaxNode[] { namespaceDeclaration },
+            [namespaceDeclaration],
             (_, _) => converted.WithAdditionalAnnotations(annotation),
-            new SyntaxToken[] { tokenAfterNamespace },
+            [tokenAfterNamespace],
             (_, _) => tokenAfterNamespace.WithLeadingTrivia(triviaAfterSplit),
             [],
             (_, _) => throw ExceptionUtilities.Unreachable());

src/Analyzers/CSharp/Tests/ImplementAbstractClass/ImplementAbstractClassTests_ThroughMember.cs

@@ -247,7 +247,7 @@ public override void Method1()
                     inner.Method1();
                 }
             }
-            """, new string[] { AnalyzersResources.Implement_abstract_class });
+            """, [AnalyzersResources.Implement_abstract_class]);
     }
 
     [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/41420")]

src/Analyzers/CSharp/Tests/SimplifyInterpolation/SimplifyInterpolationTests.cs

@@ -44,9 +44,9 @@ void M(string someValue)
         var diagnostics = await GetDiagnosticsWorkerAsync(workspace, parameters);
 
         Assert.Equal(
-            new[] {
+            [
                 ("IDE0071", DiagnosticSeverity.Info),
-            },
+            ],
             diagnostics.Select(d => (d.Descriptor.Id, d.Severity)));
     }
 

src/Analyzers/Core/Analyzers/MatchFolderAndNamespace/AbstractMatchFolderAndNamespaceDiagnosticAnalyzer.cs

@@ -148,7 +148,7 @@ private bool IsFileAndNamespaceMismatch(
         var relativeDirectoryPath = PathUtilities.GetRelativePath(
             projectDir,
             PathUtilities.GetDirectoryName(namespaceDeclaration.SyntaxTree.FilePath)!);
-        var folders = relativeDirectoryPath.Split(new[] { Path.DirectorySeparatorChar }, StringSplitOptions.RemoveEmptyEntries);
+        var folders = relativeDirectoryPath.Split([Path.DirectorySeparatorChar], StringSplitOptions.RemoveEmptyEntries);
 
         var expectedNamespace = PathMetadataUtilities.TryBuildNamespaceFromFolders(folders, GetSyntaxFacts(), rootNamespace);
 

src/Analyzers/Core/CodeFixes/DocumentationComments/AbstractAddDocCommentNodesCodeFixProvider.cs

@@ -94,7 +94,7 @@ protected async Task<Document> AddParamTagAsync(
                 nodeBeforeNewParamNode ??= summaryNode;
 
                 newDocComment = newDocComment.InsertNodesAfter(nodeBeforeNewParamNode!,
-                    new[] { GetNewNode(parameterName, isFirstNodeInComment: false) });
+                    [GetNewNode(parameterName, isFirstNodeInComment: false)]);
 
                 continue;
             }

src/Analyzers/Core/CodeFixes/ForEachCast/AbstractForEachCastCodeFixProvider.cs

@@ -96,7 +96,7 @@ private SyntaxNode GetRewrittenCollection(
                     collection,
                     generator.GenericName(
                         nameof(Enumerable.Cast),
-                        new[] { iterationVariableType })));
+                        [iterationVariableType])));
         }
         else
         {

src/Analyzers/Core/CodeFixes/ImplementInterface/ImplementInterfaceGenerator_DisposePattern.cs

@@ -101,7 +101,7 @@ private async Task<Document> AddFinalizerCommentAsync(
                                           .First();
 
             finalizer = finalizer.NormalizeWhitespace();
-            var finalizerLines = finalizer.ToFullString().Split(new[] { '\r', '\n' }, StringSplitOptions.RemoveEmptyEntries);
+            var finalizerLines = finalizer.ToFullString().Split(['\r', '\n'], StringSplitOptions.RemoveEmptyEntries);
 
             var generator = document.GetRequiredLanguageService<SyntaxGenerator>();
             var finalizerComments = this.Service.CreateCommentTrivia(finalizerLines);

src/EditorFeatures/CSharpTest/ChangeSignature/ChangeSignatureTests.cs

@@ -63,7 +63,7 @@ static void M2(int x, int y, int z) { }
         await TestChangeSignatureViaCommandAsync(
             LanguageNames.CSharp,
             markup: markup,
-            updatedSignature: new[] { 1, 0 },
+            updatedSignature: [1, 0],
             expectedUpdatedInvocationDocumentCode: expectedCode);
     }
 
@@ -92,7 +92,7 @@ static void M()
         await TestChangeSignatureViaCommandAsync(
             LanguageNames.CSharp,
             markup: markup,
-            updatedSignature: new[] { 1, 0 },
+            updatedSignature: [1, 0],
             expectedUpdatedInvocationDocumentCode: expectedCode);
     }
 

src/EditorFeatures/CSharpTest/Classification/SyntacticClassifierTests.cs

@@ -2857,7 +2857,7 @@ interface Bar
 }
 #endregion TaoRegion",
             testHost,
-            new[] { new CSharpParseOptions(LanguageVersion.CSharp8) },
+            [new CSharpParseOptions(LanguageVersion.CSharp8)],
             Keyword("using"),
             Identifier("System"),
             Punctuation.Semicolon,
@@ -5673,9 +5673,9 @@ public async Task TestXmlAttributeNameSpan1()
         using var workspace = CreateWorkspace(source, options: null, TestHost.InProcess);
         var document = workspace.CurrentSolution.Projects.First().Documents.First();
 
-        var classifications = await GetSyntacticClassificationsAsync(document, ImmutableArray.Create(new TextSpan(0, source.Length)));
-        Assert.Equal(new[]
-        {
+        var classifications = await GetSyntacticClassificationsAsync(document, [new TextSpan(0, source.Length)]);
+        AssertEx.Equal(
+        [
             new ClassifiedSpan(ClassificationTypeNames.XmlDocCommentDelimiter, new TextSpan(0, 3)),
             new ClassifiedSpan(ClassificationTypeNames.XmlDocCommentText, new TextSpan(3, 1)),
             new ClassifiedSpan(ClassificationTypeNames.XmlDocCommentDelimiter, new TextSpan(4, 1)),
@@ -5689,7 +5689,7 @@ public async Task TestXmlAttributeNameSpan1()
             new ClassifiedSpan(ClassificationTypeNames.XmlDocCommentDelimiter, new TextSpan(24, 2)),
             new ClassifiedSpan(ClassificationTypeNames.XmlDocCommentName, new TextSpan(26, 5)),
             new ClassifiedSpan(ClassificationTypeNames.XmlDocCommentDelimiter, new TextSpan(31, 1))
-        }, classifications);
+        ], classifications);
     }
 
     [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/48094")]
@@ -5701,9 +5701,9 @@ public async Task TestXmlAttributeNameSpan2()
         using var workspace = CreateWorkspace(source, options: null, TestHost.InProcess);
         var document = workspace.CurrentSolution.Projects.First().Documents.First();
 
-        var classifications = await GetSyntacticClassificationsAsync(document, ImmutableArray.Create(new TextSpan(0, source.Length)));
-        Assert.Equal(new[]
-        {
+        var classifications = await GetSyntacticClassificationsAsync(document, [new TextSpan(0, source.Length)]);
+        AssertEx.Equal(
+        [
             new ClassifiedSpan(ClassificationTypeNames.XmlDocCommentDelimiter, new TextSpan(2, 3)),
             new ClassifiedSpan(ClassificationTypeNames.XmlDocCommentText, new TextSpan(5, 1)),
             new ClassifiedSpan(ClassificationTypeNames.XmlDocCommentDelimiter, new TextSpan(6, 1)),
@@ -5718,7 +5718,7 @@ public async Task TestXmlAttributeNameSpan2()
             new ClassifiedSpan(ClassificationTypeNames.XmlDocCommentDelimiter, new TextSpan(31, 2)),
             new ClassifiedSpan(ClassificationTypeNames.XmlDocCommentName, new TextSpan(33, 5)),
             new ClassifiedSpan(ClassificationTypeNames.XmlDocCommentDelimiter, new TextSpan(38, 1))
-        }, classifications);
+        ], classifications);
     }
 
     [Theory, WorkItem("https://github.com/dotnet/roslyn/issues/52290")]

src/EditorFeatures/CSharpTest/Classification/TotalClassifierTests.cs

@@ -3074,8 +3074,8 @@ void M()
 
         var actualFormatted = actualOrdered.Select(a => new FormattedClassification(allCode.Substring(a.Span.Span.Start, a.Span.Span.Length), a.Tag.ClassificationType.Classification));
 
-        AssertEx.Equal(new[]
-        {
+        AssertEx.Equal(
+        [
             Keyword("using"),
             Namespace("System"),
             Operators.Dot,
@@ -3130,7 +3130,7 @@ void M()
             Punctuation.Semicolon,
             Punctuation.CloseCurly,
             Punctuation.CloseCurly,
-        }, actualFormatted);
+        ], actualFormatted);
     }
 
     [WpfFact]
@@ -3175,8 +3175,8 @@ void M()
 
         var actualFormatted = actualOrdered.Select(a => new FormattedClassification(allCode.Substring(a.Span.Span.Start, a.Span.Span.Length), a.Tag.ClassificationType.Classification));
 
-        AssertEx.Equal(new[]
-        {
+        AssertEx.Equal(
+        [
             Keyword("using"),
             Namespace("System"),
             Operators.Dot,
@@ -3231,6 +3231,6 @@ void M()
             Punctuation.Semicolon,
             Punctuation.CloseCurly,
             Punctuation.CloseCurly,
-        }, actualFormatted);
+        ], actualFormatted);
     }
 }

src/EditorFeatures/CSharpTest/CodeActions/GenerateType/GenerateTypeTests.cs

@@ -4824,12 +4824,11 @@ static void Main(string[] args)
 ";
 
         await TestExactActionSetOfferedAsync(code,
-            new[]
-            {
+            [
                 string.Format(FeaturesResources.Generate_0_1_in_new_file, "class", "Goo"),
                 string.Format(FeaturesResources.Generate_nested_0_1, "class", "Goo", "Program"),
                 FeaturesResources.Generate_new_type
-            });
+            ]);
 
         await TestInRegularAndScriptAsync(code,
 @"

src/EditorFeatures/CSharpTest/CodeActions/GenerateType/GenerateTypeTests_Dialog.cs

@@ -3012,7 +3012,7 @@ public class B
 accessibility: Accessibility.Public,
 typeKind: TypeKind.Class,
 isNewFile: false,
-assertTypeKindAbsent: new[] { TypeKindOptions.Enum });
+assertTypeKindAbsent: [TypeKindOptions.Enum]);
     }
 
     [Fact]
@@ -3049,7 +3049,7 @@ public class B
 accessibility: Accessibility.Public,
 typeKind: TypeKind.Class,
 isNewFile: false,
-assertTypeKindAbsent: new[] { TypeKindOptions.Enum });
+assertTypeKindAbsent: [TypeKindOptions.Enum]);
     }
 
     [Fact]

src/EditorFeatures/CSharpTest/CodeActions/MoveType/MoveTypeTests.RenameFile.cs

@@ -72,7 +72,7 @@ class Inner { }
         var expectedDocumentName = "Class1.cs";
 
         await TestRenameFileToMatchTypeAsync(code, expectedDocumentName,
-            destinationDocumentContainers: new[] { "A", "B" });
+            destinationDocumentContainers: ["A", "B"]);
     }
 
     [Fact]

src/EditorFeatures/CSharpTest/Completion/CompletionProviders/CrefCompletionProviderTests.cs

@@ -441,7 +441,7 @@ class C
             {
             }
             """;
-        using var workspace = EditorTestWorkspace.Create(LanguageNames.CSharp, new CSharpCompilationOptions(OutputKind.ConsoleApplication), new CSharpParseOptions(), new[] { text }, composition: GetComposition());
+        using var workspace = EditorTestWorkspace.Create(LanguageNames.CSharp, new CSharpCompilationOptions(OutputKind.ConsoleApplication), new CSharpParseOptions(), [text], composition: GetComposition());
         var called = false;
 
         var hostDocument = workspace.DocumentWithCursor;

src/EditorFeatures/CSharpTest/Completion/CompletionProviders/DeclarationNameCompletionProviderTests.cs

@@ -1170,7 +1170,7 @@ public class MyClass
             """;
         var items = await GetCompletionItemsAsync(markup, SourceCodeKind.Regular);
         Assert.Equal(
-            new[] { "myClass", "my", "@class", "MyClass", "My", "Class", "GetMyClass", "GetMy", "GetClass" },
+            ["myClass", "my", "@class", "MyClass", "My", "Class", "GetMyClass", "GetMy", "GetClass"],
             items.Select(item => item.DisplayText));
     }
 

src/EditorFeatures/CSharpTest/Completion/CompletionProviders/OverrideCompletionProviderTests.cs

@@ -3055,7 +3055,7 @@ static void Main(string[] args)
         override $$
     }
 }";
-        using var workspace = EditorTestWorkspace.Create(LanguageNames.CSharp, new CSharpCompilationOptions(OutputKind.ConsoleApplication), new CSharpParseOptions(), new[] { text }, composition: GetComposition());
+        using var workspace = EditorTestWorkspace.Create(LanguageNames.CSharp, new CSharpCompilationOptions(OutputKind.ConsoleApplication), new CSharpParseOptions(), [text], composition: GetComposition());
         var provider = new OverrideCompletionProvider();
         var testDocument = workspace.Documents.Single();
         var document = workspace.CurrentSolution.GetRequiredDocument(testDocument.Id);

src/EditorFeatures/CSharpTest/Completion/CompletionProviders/ReferenceDirectiveCompletionProviderTests.cs

@@ -48,7 +48,7 @@ private protected override Task VerifyWorkerAsync(
     [Fact]
     public async Task IsCommitCharacterTest()
     {
-        var commitCharacters = PathUtilities.IsUnixLikePlatform ? new[] { '"', '/' } : new[] { '"', '\\', '/', ',' };
+        var commitCharacters = PathUtilities.IsUnixLikePlatform ? new[] { '"', '/' } : ['"', '\\', '/', ','];
         await VerifyCommitCharactersAsync("#r \"$$", textTypedSoFar: "", validChars: commitCharacters, sourceCodeKind: SourceCodeKind.Script);
     }