ExtractSemanticDB.PostInlining now update the .semanticdb file on disk

compiler/src/dotty/tools/dotc/semanticdb/ExtractSemanticDB.scala

@@ -27,6 +27,7 @@ import dotty.tools.dotc.{semanticdb => s}
 import dotty.tools.io.{AbstractFile, JarArchive}
 import dotty.tools.dotc.util.Property
 import dotty.tools.dotc.semanticdb.DiagnosticOps.*
+import scala.util.{Using, Failure, Success}
 
 
 /** Extract symbol references and uses to semanticdb files.
@@ -36,17 +37,15 @@ import dotty.tools.dotc.semanticdb.DiagnosticOps.*
  *  Here, we define two phases for "ExtractSemanticDB", "PostTyper" and "PostInlining".
  *
  *  The "PostTyper" phase extracts SemanticDB information such as symbol
- *  definitions, symbol occurrences, type information, and synthetics.
- *  This phase does not write the information to a .semanticdb file;
- *  instead, it attaches the SemanticDB information to the top-level tree.
+ *  definitions, symbol occurrences, type information, and synthetics
+ *  and write .semanticdb file.
  *
  *  The "PostInlining" phase extracts diagnostics from "ctx.reporter" and
  *  attaches them to the SemanticDB information extracted in the "PostTyper" phase.
- *  Afterwards, it writes the SemanticDB to a ".semanticdb" file.
  *  We need to run this phase after the "CheckUnused.PostInlining" phase
  *  so that we can extract the warnings generated by "-Wunused".
  */
-class ExtractSemanticDB private (phaseMode: ExtractSemanticDB.PhaseMode, suffix: String, _key: Property.Key[TextDocument]) extends Phase:
+class ExtractSemanticDB private (phaseMode: ExtractSemanticDB.PhaseMode, suffix: String) extends Phase:
 
   override val phaseName: String = ExtractSemanticDB.phaseNamePrefix + suffix
 
@@ -65,15 +64,13 @@ class ExtractSemanticDB private (phaseMode: ExtractSemanticDB.PhaseMode, suffix:
     if (phaseMode == ExtractSemanticDB.PhaseMode.PostTyper)
       val extractor = ExtractSemanticDB.Extractor()
       extractor.extract(unit.tpdTree)
-      unit.tpdTree.putAttachment(_key, extractor.toTextDocument(unit.source))
+      ExtractSemanticDB.write(unit.source, extractor.occurrences.toList, extractor.symbolInfos.toList, extractor.synthetics.toList)
     else
-      unit.tpdTree.getAttachment(_key) match
-        case None =>
-        case Some(doc) =>
-          val warnings = ctx.reporter.allWarnings.collect {
-            case w if w.pos.source == ctx.source => w.toSemanticDiagnostic
-          }
-          ExtractSemanticDB.write(unit.source, doc.copy(diagnostics = warnings))
+      val warnings = ctx.reporter.allWarnings.collect {
+        case w if w.pos.source == ctx.source => w.toSemanticDiagnostic
+      }
+      if (warnings.nonEmpty)
+        ExtractSemanticDB.appendDiagnostics(unit.source, warnings)
 end ExtractSemanticDB
 
 object ExtractSemanticDB:
@@ -88,15 +85,9 @@ object ExtractSemanticDB:
     case PostTyper
     case PostInlining
 
-  /**
-   * The key used to retrieve the "unused entity" analysis metadata,
-   * from the compilation `Context`
-   */
-  private val _key = Property.StickyKey[TextDocument]
+  class PostTyper extends ExtractSemanticDB(PhaseMode.PostTyper, "PostTyper")
 
-  class PostTyper extends ExtractSemanticDB(PhaseMode.PostTyper, "PostTyper", _key)
-
-  class PostInlining extends ExtractSemanticDB(PhaseMode.PostInlining, "PostInlining", _key)
+  class PostInlining extends ExtractSemanticDB(PhaseMode.PostInlining, "PostInlining")
 
   private def semanticdbTarget(using Context): Option[Path] =
     Option(ctx.settings.semanticdbTarget.value)
@@ -109,15 +100,22 @@ object ExtractSemanticDB:
 
   private def write(
     source: SourceFile,
-    doc: TextDocument
+    occurrences: List[SymbolOccurrence],
+    symbolInfos: List[SymbolInformation],
+    synthetics: List[Synthetic],
   )(using Context): Unit =
-    val relPath = SourceFile.relativePath(source, ctx.settings.sourceroot.value)
-    val outpath = absolutePath(semanticdbTarget.getOrElse(outputDirectory.jpath))
-      .resolve("META-INF")
-      .resolve("semanticdb")
-      .resolve(relPath)
-      .resolveSibling(source.name + ".semanticdb")
+    val outpath = semanticdbPath(source)
     Files.createDirectories(outpath.getParent())
+    val doc: TextDocument = TextDocument(
+      schema = Schema.SEMANTICDB4,
+      language = Language.SCALA,
+      uri = Tools.mkURIstring(Paths.get(relPath(source))),
+      text = "",
+      md5 = internal.MD5.compute(String(source.content)),
+      symbols = symbolInfos,
+      occurrences = occurrences,
+      synthetics = synthetics,
+    )
     val docs = TextDocuments(List(doc))
     val out = Files.newOutputStream(outpath)
     try
@@ -128,6 +126,34 @@ object ExtractSemanticDB:
       out.close()
   end write
 
+  private def appendDiagnostics(
+    source: SourceFile,
+    diagnostics: Seq[Diagnostic]
+  )(using Context): Unit =
+    val path = semanticdbPath(source)
+    Using.Manager { use =>
+      val in = use(Files.newInputStream(path))
+      val sin = internal.SemanticdbInputStream.newInstance(in)
+      val docs = TextDocuments.parseFrom(sin)
+
+      val out = use(Files.newOutputStream(path))
+      val sout = internal.SemanticdbOutputStream.newInstance(out)
+      TextDocuments(docs.documents.map(_.withDiagnostics(diagnostics))).writeTo(sout)
+      sout.flush()
+    } match
+      case Failure(ex) => // failed somehow, should we say something?
+      case Success(_) => // success to update semanticdb, say nothing
+  end appendDiagnostics
+
+  private def relPath(source: SourceFile)(using ctx: Context) =
+    SourceFile.relativePath(source, ctx.settings.sourceroot.value)
+
+  private def semanticdbPath(source: SourceFile)(using ctx: Context) =
+    absolutePath(semanticdbTarget.getOrElse(outputDirectory.jpath))
+      .resolve("META-INF")
+      .resolve("semanticdb")
+      .resolve(relPath(source))
+      .resolveSibling(source.name + ".semanticdb")
 
   /** Extractor of symbol occurrences from trees */
   private class Extractor extends TreeTraverser:
@@ -136,20 +162,6 @@ object ExtractSemanticDB:
     val synth = SyntheticsExtractor()
     given converter: s.TypeOps = s.TypeOps()
 
-
-    def toTextDocument(source: SourceFile)(using Context): TextDocument =
-      val relPath = SourceFile.relativePath(source, ctx.settings.sourceroot.value)
-      TextDocument(
-        schema = Schema.SEMANTICDB4,
-        language = Language.SCALA,
-        uri = Tools.mkURIstring(Paths.get(relPath)),
-        text = "",
-        md5 = internal.MD5.compute(String(source.content)),
-        symbols = symbolInfos.toList,
-        occurrences = occurrences.toList,
-        synthetics = synthetics.toList,
-      )
-
     /** The bodies of synthetic locals */
     private val localBodies = mutable.HashMap[Symbol, Tree]()