WIP - embed source files into PDB

src/Compilers/CSharp/Portable/CommandLine/CSharpCompiler.cs

@@ -160,7 +160,14 @@ private SyntaxTree ParseFile(
             }
             else
             {
-                return ParseFile(parseOptions, scriptParseOptions, content, file);
+                SyntaxTree tree = ParseFile(parseOptions, scriptParseOptions, content, file);
+                if(Arguments.EmbedSourceInPdb)
+                {
+                    SyntaxNode root = tree.GetRoot();
+                    root = root.WithAdditionalAnnotations(new SyntaxAnnotation("EmbedSourceInPdb"));
+                    tree = tree.WithRootAndOptions(root, tree.Options);
+                }
+                return tree;
             }
         }
 

src/Compilers/CSharp/Portable/CommandLine/CommandLineParser.cs

@@ -58,6 +58,7 @@ internal sealed override CommandLineArguments CommonParse(IEnumerable<string> ar
             bool concurrentBuild = true;
             bool emitPdb = false;
             string pdbPath = null;
+            bool embedSourceInPdb = false;
             bool noStdLib = false;
             string outputDirectory = baseDirectory;
             string outputFileName = null;
@@ -971,6 +972,9 @@ internal sealed override CommandLineArguments CommonParse(IEnumerable<string> ar
 
                             additionalFiles.AddRange(ParseAdditionalFileArgument(value, baseDirectory, diagnostics));
                             continue;
+                        case "embedSource":
+                            embedSourceInPdb = true;
+                            continue;
                     }
                 }
 
@@ -1102,6 +1106,7 @@ internal sealed override CommandLineArguments CommonParse(IEnumerable<string> ar
                 OutputFileName = outputFileName,
                 PdbPath = pdbPath,
                 EmitPdb = emitPdb,
+                EmbedSourceInPdb = embedSourceInPdb,
                 OutputDirectory = outputDirectory,
                 DocumentationPath = documentationPath,
                 ErrorLogPath = errorLogPath,

src/Compilers/CSharp/Portable/Compilation/CSharpCompilation.cs

@@ -2612,9 +2612,20 @@ private static ImmutableArray<byte> MakeChecksumBytes(string bytesText)
             return builder.ToImmutableAndFree();
         }
 
+        private static bool IsSyntaxTreePdbEmbedded(SyntaxTree tree)
+        {
+            return tree.GetRoot().GetAnnotations().Any(a => a.Kind == "EmbedSourceInPdb");
+        }
+
         private static Cci.DebugSourceDocument MakeDebugSourceDocumentForTree(string normalizedPath, SyntaxTree tree)
         {
-            return new Cci.DebugSourceDocument(normalizedPath, Cci.DebugSourceDocument.CorSymLanguageTypeCSharp, () => tree.GetChecksumAndAlgorithm());
+            byte[] pdbEmbeddedSourceBytes = null;
+            if(IsSyntaxTreePdbEmbedded(tree))
+            {
+                SourceText text = tree.GetText();
+                pdbEmbeddedSourceBytes = text.Encoding.GetBytes(text.ToString());
+            }
+            return new Cci.DebugSourceDocument(normalizedPath, Cci.DebugSourceDocument.CorSymLanguageTypeCSharp, () => tree.GetChecksumAndAlgorithm(), pdbEmbeddedSourceBytes);
         }
 
         private void SetupWin32Resources(PEModuleBuilder moduleBeingBuilt, Stream win32Resources, DiagnosticBag diagnostics)

src/Compilers/Core/Portable/CommandLine/CommonCommandLineArguments.cs

@@ -74,6 +74,11 @@ public abstract class CommandLineArguments
         /// </summary>
         public bool EmitPdb { get; internal set; }
 
+        /// <summary>
+        /// True to embed source files in the PDB.
+        /// </summary>
+        public bool EmbedSourceInPdb { get; internal set; }
+
         /// <summary>
         /// Absolute path of the output directory.
         /// </summary>

src/Compilers/Core/Portable/NativePdbWriter/PdbWriter.cs

@@ -132,7 +132,8 @@ internal enum PdbWriterOperation : byte
             DefineKickoffMethod,
             OpenMapTokensToSourceSpans,
             MapTokenToSourceSpan,
-            CloseMapTokensToSourceSpans
+            CloseMapTokensToSourceSpans,
+            SetSource
         }
 
         public bool LogOperation(PdbWriterOperation op)
@@ -949,6 +950,16 @@ private ISymUnmanagedDocumentWriter GetDocumentWriter(DebugSourceDocument docume
                         _callLogger.LogArgument(vendor.ToByteArray());
                         _callLogger.LogArgument(type.ToByteArray());
                     }
+                    if(document.EmbeddedSource != null)
+                    {
+                        writer.SetSource((uint)document.EmbeddedSource.Length, document.EmbeddedSource);
+                        if (_callLogger.LogOperation(OP.SetSource))
+                        {
+                            //logging length is irrelevant, it has no additional entropy
+                            //for performance it might be better to log ChecksumAndAlgorithm instead?
+                            _callLogger.LogArgument(document.EmbeddedSource);
+                        }
+                    }
                 }
                 catch (Exception ex)
                 {

src/Compilers/Core/Portable/PEWriter/DebugSourceDocument.cs

@@ -19,6 +19,7 @@ internal sealed class DebugSourceDocument
         private readonly string _location;
         private readonly Guid _language;
         private readonly bool _isComputedChecksum;
+        private readonly byte[] _embeddedSource;
 
         private readonly Task<ValueTuple<ImmutableArray<byte>, Guid>> _checksumAndAlgorithm;
 
@@ -33,11 +34,12 @@ public DebugSourceDocument(string location, Guid language)
         /// <summary>
         /// Use to create a document when checksum is computed based on actual source stream.
         /// </summary>
-        public DebugSourceDocument(string location, Guid language, Func<ValueTuple<ImmutableArray<byte>, Guid>> checksumAndAlgorithm)
+        public DebugSourceDocument(string location, Guid language, Func<ValueTuple<ImmutableArray<byte>, Guid>> checksumAndAlgorithm, byte[] embeddedSource = null)
             : this(location, language)
         {
             _checksumAndAlgorithm = Task.Run(checksumAndAlgorithm);
             _isComputedChecksum = true;
+            _embeddedSource = embeddedSource;
         }
 
         /// <summary>
@@ -108,6 +110,14 @@ public ValueTuple<ImmutableArray<byte>, Guid> ChecksumAndAlgorithm
             }
         }
 
+        public byte[] EmbeddedSource
+        {
+            get
+            {
+                return _embeddedSource;
+            }
+        }
+
         /// <summary>
         /// returns true when checksum was computed base on an actual source stream
         /// as opposed to be suggested via a checksum directive/pragma
@@ -119,5 +129,7 @@ internal bool IsComputedChecksum
                 return _isComputedChecksum;
             }
         }
+
+
     }
 }

src/Compilers/Core/Portable/PublicAPI.Unshipped.txt

@@ -1,4 +1,5 @@
 *REMOVED*static Microsoft.CodeAnalysis.SyntaxNodeExtensions.NormalizeWhitespace<TNode>(this TNode node, string indentation = "    ", bool elasticTrivia = false) -> TNode
+Microsoft.CodeAnalysis.CommandLineArguments.EmbedSourceInPdb.get -> bool
 Microsoft.CodeAnalysis.CommandLineArguments.ScriptArguments.get -> System.Collections.Immutable.ImmutableArray<string>
 Microsoft.CodeAnalysis.CommandLineParser.IsInteractive.get -> bool
 Microsoft.CodeAnalysis.Compilation.GetSubmissionResultType(out bool hasValue) -> Microsoft.CodeAnalysis.ITypeSymbol