C#: Use * ID for Locations in buildless.

Author: michaelnebel

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

@@ -72,15 +72,14 @@ public static Assembly CreateOutputAssembly(Context cx)
 
         public override void WriteId(EscapingTextWriter trapFile)
         {
-            if (isOutputAssembly && Context.ExtractionContext.IsStandalone)
+            if (Context.ExtractionContext.IsStandalone)
             {
-                trapFile.Write("buildlessOutputAssembly");
-            }
-            else
-            {
-                trapFile.Write(assembly.ToString());
+                WriteStarId(trapFile);
+                return;
             }
 
+            trapFile.Write(assembly.ToString());
+
             if (assemblyPath is not null)
             {
                 trapFile.Write("#file:///");

csharp/extractor/Semmle.Extraction.CSharp/Entities/Locations/GeneratedLocation.cs

@@ -19,6 +19,12 @@ public override void Populate(TextWriter trapFile)
 
         public override void WriteId(EscapingTextWriter trapFile)
         {
+            if (Context.ExtractionContext.IsStandalone)
+            {
+                WriteStarId(trapFile);
+                return;
+            }
+
             trapFile.Write("loc,");
             trapFile.WriteSubId(generatedFile);
             trapFile.Write(",0,0,0,0");

csharp/extractor/Semmle.Extraction.CSharp/Entities/Locations/Location.cs

@@ -5,7 +5,29 @@ public abstract class Location : CachedEntity<Microsoft.CodeAnalysis.Location?>
     {
 #nullable restore warnings
         protected Location(Context cx, Microsoft.CodeAnalysis.Location? init)
-            : base(cx, init) { }
+            : base(cx, init)
+        {
+            if (cx.ExtractionContext.IsStandalone)
+            {
+                cx.AddFreshLabel(this);
+            }
+        }
+
+        protected static void WriteStarId(EscapingTextWriter writer)
+        {
+            writer.Write('*');
+        }
+
+        public sealed override void WriteQuotedId(EscapingTextWriter writer)
+        {
+            if (Context.ExtractionContext.IsStandalone)
+            {
+                WriteStarId(writer);
+                return;
+            }
+
+            base.WriteQuotedId(writer);
+        }
 
         public override Microsoft.CodeAnalysis.Location? ReportingLocation => Symbol;
 

csharp/extractor/Semmle.Extraction.CSharp/Entities/Locations/NonGeneratedSourceLocation.cs

@@ -42,6 +42,12 @@ public File FileEntity
 
         public override void WriteId(EscapingTextWriter trapFile)
         {
+            if (Context.ExtractionContext.IsStandalone)
+            {
+                WriteStarId(trapFile);
+                return;
+            }
+
             trapFile.Write("loc,");
             trapFile.WriteSubId(FileEntity);
             trapFile.Write(',');