C#: Make extractor support for file scoped types.

Author: michaelnebel

csharp/extractor/Semmle.Extraction.CSharp/Entities/Modifier.cs

@@ -85,6 +85,9 @@ private static void ExtractNamedTypeModifiers(Context cx, TextWriter trapFile, I
             if (nt.IsRecord)
                 HasModifier(cx, trapFile, key, Modifiers.Record);
 
+            if (nt.IsFileLocal)
+                HasModifier(cx, trapFile, key, Modifiers.File);
+
             if (nt.TypeKind == TypeKind.Struct)
             {
                 if (nt.IsReadOnly)
@@ -97,7 +100,9 @@ private static void ExtractNamedTypeModifiers(Context cx, TextWriter trapFile, I
 
         public static void ExtractModifiers(Context cx, TextWriter trapFile, IEntity key, ISymbol symbol)
         {
-            HasAccessibility(cx, trapFile, key, symbol.DeclaredAccessibility);
+            if (symbol.Kind != SymbolKind.NamedType || !((INamedTypeSymbol)symbol).IsFileLocal)
+                HasAccessibility(cx, trapFile, key, symbol.DeclaredAccessibility);
+
             if (symbol.Kind == SymbolKind.ErrorType)
                 trapFile.has_modifiers(key, Modifier.Create(cx, Accessibility.Public));
 

csharp/extractor/Semmle.Extraction.CSharp/Entities/Modifiers.cs

@@ -4,6 +4,7 @@ internal static class Modifiers
     public const string Async = "async";
     public const string Const = "const";
     public const string Extern = "extern";
+    public const string File = "file";
     public const string Internal = "internal";
     public const string New = "new";
     public const string Override = "override";

csharp/extractor/Semmle.Extraction.CSharp/SymbolExtensions.cs

@@ -286,7 +286,7 @@ private static void BuildFunctionPointerTypeId(this IFunctionPointerTypeSymbol f
         public static IEnumerable<IFieldSymbol?> GetTupleElementsMaybeNull(this INamedTypeSymbol type) =>
             type.TupleElements;
 
-        private static void AddContaining(INamedTypeSymbol named, Context cx, EscapingTextWriter trapFile, ISymbol symbolBeingDefined)
+        private static void BuildQualifierAndName(INamedTypeSymbol named, Context cx, EscapingTextWriter trapFile, ISymbol symbolBeingDefined)
         {
             if (named.ContainingType is not null)
             {
@@ -299,6 +299,9 @@ private static void AddContaining(INamedTypeSymbol named, Context cx, EscapingTe
                     BuildAssembly(named.ContainingAssembly, trapFile);
                 named.ContainingNamespace.BuildNamespace(cx, trapFile);
             }
+
+            var name = named.IsFileLocal ? named.MetadataName : named.Name;
+            trapFile.Write(name);
         }
 
         private static void BuildTupleId(INamedTypeSymbol named, Context cx, EscapingTextWriter trapFile, ISymbol symbolBeingDefined)
@@ -332,13 +335,11 @@ private static void BuildNamedTypeId(this INamedTypeSymbol named, Context cx, Es
 
             if (named.TypeParameters.IsEmpty)
             {
-                AddContaining(named, cx, trapFile, symbolBeingDefined);
-                trapFile.Write(named.Name);
+                BuildQualifierAndName(named, cx, trapFile, symbolBeingDefined);
             }
             else if (named.IsReallyUnbound())
             {
-                AddContaining(named, cx, trapFile, symbolBeingDefined);
-                trapFile.Write(named.Name);
+                BuildQualifierAndName(named, cx, trapFile, symbolBeingDefined);
                 trapFile.Write("`");
                 trapFile.Write(named.TypeParameters.Length);
             }