Simplify collections. Make local functions static.

src/EditorFeatures/CSharpTest/CodeActions/SyncNamespace/SyncNamespaceTests_MoveFile.cs

@@ -47,8 +47,10 @@ public async Task MoveFile_SingleAction1()
             var defaultNamespace = "A";
             var declaredNamespace = "A.B.C";
 
-            var expectedFolders = new List<string[]>();
-            expectedFolders.Add(new[] { "B", "C" });
+            var expectedFolders = new List<string[]>
+            {
+                new[] { "B", "C" }
+            };
 
             var documentPath = CreateDocumentFilePath(Array.Empty<string>());
             var code =
@@ -77,8 +79,10 @@ public async Task MoveFile_SingleAction2()
             var defaultNamespace = "A";
             var declaredNamespace = "A.B.C.D.E";
 
-            var expectedFolders = new List<string[]>();
-            expectedFolders.Add(new[] { "B", "C", "D", "E" });
+            var expectedFolders = new List<string[]>
+            {
+                new[] { "B", "C", "D", "E" }
+            };
 
             var documentPath1 = CreateDocumentFilePath(Array.Empty<string>(), "File1.cs");
             var documentPath2 = CreateDocumentFilePath(new[] { "B", "C" }, "File2.cs");   // file2 is in <root>\B\C\
@@ -115,8 +119,10 @@ public async Task MoveFile_MoveToRoot()
 
             var defaultNamespace = "";
 
-            var expectedFolders = new List<string[]>();
-            expectedFolders.Add(Array.Empty<string>());
+            var expectedFolders = new List<string[]>
+            {
+                Array.Empty<string>()
+            };
 
             var documentPath = CreateDocumentFilePath(new[] { "A", "B", "C" });
             var code =

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

@@ -1910,7 +1910,7 @@ private static NamingStylePreferences NamesEndWithSuffixPreferences()
 
             // Local functions
 
-            (SymbolSpecification specification, NamingStyle style) SpecificationStyle(SymbolKindOrTypeKind kind, string suffix)
+            static (SymbolSpecification specification, NamingStyle style) SpecificationStyle(SymbolKindOrTypeKind kind, string suffix)
             {
                 var symbolSpecification = new SymbolSpecification(
                     id: null,
@@ -1930,7 +1930,7 @@ private static NamingStylePreferences NamesEndWithSuffixPreferences()
                 return (symbolSpecification, namingStyle);
             }
 
-            SerializableNamingRule CreateRule(SymbolSpecification specification, NamingStyle style)
+            static SerializableNamingRule CreateRule(SymbolSpecification specification, NamingStyle style)
             {
                 return new SerializableNamingRule()
                 {

src/EditorFeatures/CSharpTest/EditAndContinue/EditSessionTests.cs

@@ -323,7 +323,7 @@ static void Main()
             //   Test2.M2: adding a line in front of try-catch.
             //   Test2.F2: moving the entire method 2 lines down.
 
-            LinePositionSpan AddDelta(LinePositionSpan span, int lineDelta)
+            static LinePositionSpan AddDelta(LinePositionSpan span, int lineDelta)
                 => new LinePositionSpan(new LinePosition(span.Start.Line + lineDelta, span.Start.Character), new LinePosition(span.End.Line + lineDelta, span.End.Character));
 
             var newActiveStatementsInChangedDocuments = ImmutableArray.Create(

src/EditorFeatures/CSharpTest/Semantics/SpeculationAnalyzerTests.cs

@@ -512,7 +512,7 @@ protected override Compilation CreateCompilation(SyntaxTree tree)
         protected override bool CompilationSucceeded(Compilation compilation, Stream temporaryStream)
         {
             var langCompilation = compilation;
-            bool isProblem(Diagnostic d) => d.Severity >= DiagnosticSeverity.Warning;
+            static bool isProblem(Diagnostic d) => d.Severity >= DiagnosticSeverity.Warning;
             return !langCompilation.GetDiagnostics().Any(isProblem) &&
                 !langCompilation.Emit(temporaryStream).Diagnostics.Any(isProblem);
         }

src/VisualStudio/Core/Def/Implementation/TableDataSource/TableEntriesFactory.cs

@@ -248,8 +248,10 @@ private void EnsureSources()
                 {
                     if (_sources == null)
                     {
-                        _sources = new Dictionary<object, AbstractTableEntriesSource<TItem>>();
-                        _sources.Add(_primary.Key, _primary);
+                        _sources = new Dictionary<object, AbstractTableEntriesSource<TItem>>
+                        {
+                            { _primary.Key, _primary }
+                        };
                         _primary = null;
                     }
                 }

src/VisualStudio/IntegrationTest/IntegrationTests/AbstractUpdateProjectTest.cs

@@ -32,7 +32,7 @@ protected static void VerifyPropertyOutsideConfiguration(XElement projectElement
                 projectElement.Elements().Where(IsUnconditionalPropertyGroup),
                 group => GetPropertyValue(group, name) == value);
 
-            bool IsUnconditionalPropertyGroup(XElement element)
+            static bool IsUnconditionalPropertyGroup(XElement element)
                 => element.Name.LocalName == "PropertyGroup" && !element.Attributes().Any(a => a.Name.LocalName == "Condition");
         }
 
@@ -42,7 +42,7 @@ protected static void VerifyPropertyInEachConfiguration(XElement projectElement,
                 projectElement.Elements().Where(IsConditionalPropertyGroup),
                 group => Assert.Equal(value, GetPropertyValue(group, name)));
 
-            bool IsConditionalPropertyGroup(XElement element)
+            static bool IsConditionalPropertyGroup(XElement element)
                 => element.Name.LocalName == "PropertyGroup" && element.Attributes().Any(a => a.Name.LocalName == "Condition");
         }