Drop SemanticdbAgent, PackageHub, and other dead code paths (#902)

Author: jupblb

bin/packagehub.sh

@@ -15,7 +15,6 @@ lazy val V =
     val gradle = "7.0"
     val scala213 = "2.13.13"
     val scalameta = "4.9.3"
-    val requests = "0.8.0"
     val kotlinVersion = "2.2.0"
     val kotest = "4.6.3"
     val kctfork = "0.7.1"
@@ -86,25 +85,6 @@ lazy val semanticdbShared = project
     libraryDependencies += "com.google.protobuf" % "protobuf-java" % V.protobuf
   )
 
-lazy val agent = project
-  .in(file("semanticdb-agent"))
-  .settings(
-    fatjarPackageSettings,
-    javaOnlySettings,
-    moduleName := "semanticdb-agent",
-    libraryDependencies ++=
-      List(
-        "net.bytebuddy" % "byte-buddy" % "1.15.11",
-        "net.bytebuddy" % "byte-buddy-agent" % "1.15.11"
-      ),
-    Compile / packageBin / packageOptions +=
-      Package.ManifestAttributes(
-        "Agent-Class" -> "com.sourcegraph.semanticdb_javac.SemanticdbAgent",
-        "Can-Redefine-Classes" -> "true",
-        "Can-Retransform-Classes" -> "true",
-        "Premain-Class" -> "com.sourcegraph.semanticdb_javac.SemanticdbAgent"
-      )
-  )
 lazy val gradlePlugin = project
   .in(file("semanticdb-gradle-plugin"))
   .settings(
@@ -155,10 +135,6 @@ lazy val javacPlugin = project
             // referenced from META-INF/services/com.sun.source.util.Plugin
             "com.sourcegraph.semanticdb_javac.SemanticdbPlugin" ->
               "com.sourcegraph.semanticdb_javac.SemanticdbPlugin",
-            // Don't rename PrintJavaVersion because we load it via FQN to
-            // detect the Java of a JVM installation.
-            "com.sourcegraph.semanticdb_javac.PrintJavaVersion" ->
-              "com.sourcegraph.semanticdb_javac.PrintJavaVersion",
             // Don't rename InjectSemanticdbOptions because we load it via FQN to
             // process a list of Java compiler options.
             "com.sourcegraph.semanticdb_javac.InjectSemanticdbOptions" ->
@@ -243,7 +219,6 @@ lazy val cli = project
     libraryDependencies ++=
       List(
         "org.scala-lang.modules" %% "scala-xml" % V.scalaXml,
-        "com.lihaoyi" %% "requests" % V.requests,
         "org.scalameta" %% "moped" % V.moped,
         "org.jetbrains.kotlin" % "kotlin-compiler-embeddable" % V.kotlinVersion,
         "org.jetbrains.kotlin" % "kotlin-scripting-common" % V.kotlinVersion,
@@ -267,10 +242,6 @@ lazy val cli = project
             (javacPlugin / Compile / Keys.`package`).value,
             "semanticdb-plugin.jar"
           )
-          addJar(
-            (agent / Compile / Keys.`package`).value,
-            "semanticdb-agent.jar"
-          )
           addJar((gradlePlugin / Compile / assembly).value, "gradle-plugin.jar")
           addJar(
             (semanticdbKotlinc / Compile / Keys.`package`).value,
@@ -532,16 +503,6 @@ lazy val semanticdbKotlincMinimized = project
         .value
   )
 
-commands +=
-  Command.command("nativeImageProfiled") { s =>
-    val targetroot =
-      file("tests/minimized/.j11/target/scala-2.13/meta").absolutePath
-    val output = Files.createTempFile("scip-java", "index.scip")
-    "minimized/compile" ::
-      s"""nativeImageRunAgent " index-semanticdb --output=$output $targetroot"""" ::
-      "nativeImage" :: s
-  }
-
 def minimizedSourceDirectory =
   file("tests/minimized/src/main/java").getAbsoluteFile
 
@@ -577,7 +538,7 @@ lazy val minimizedSettings = List[Def.Setting[_]](
 lazy val minimized = project
   .in(file("tests/minimized/.j11"))
   .settings(minimizedSettings, javaOnlySettings)
-  .dependsOn(agent, javacPlugin)
+  .dependsOn(javacPlugin)
   .disablePlugins(JavaFormatterPlugin)
 
 def javacModuleOptions = List(
@@ -617,15 +578,6 @@ lazy val buildTools = project
   .in(file("tests/buildTools"))
   .settings(
     testSettings,
-    (Test / javaOptions) ++=
-      List(
-        s"-javaagent:${(agent / Compile / Keys.`package`).value}",
-        s"-Dsemanticdb.pluginpath=${(javacPlugin / Compile / Keys.`package`)
-            .value}",
-        s"-Dsemanticdb.sourceroot=${(ThisBuild / baseDirectory).value}",
-        s"-Dsemanticdb.targetroot=${(agent / Compile / target).value /
-            "semanticdb-targetroot"}"
-      ),
     Test / envVars ++=
       Map(
         "SCIP_JAVA_CLI" -> ((cli / pack).value / "bin" / "scip-java").toString
@@ -635,7 +587,7 @@ lazy val buildTools = project
     // everything worse
     Test / testForkedParallel := !sys.env.contains("CI")
   )
-  .dependsOn(agent, unit)
+  .dependsOn(unit)
 
 lazy val snapshots = project
   .in(file("tests/snapshots"))

build.sbt

@@ -21,21 +21,14 @@ object Embedded {
     "gradle-plugin.jar"
   )
 
-  def agentJar(tmpDir: Path): Path = copyFile(tmpDir, "semanticdb-agent.jar")
-
   def semanticdbKotlincJar(tmpDir: Path): Path = copyFile(
     tmpDir,
     "semanticdb-kotlinc.jar"
   )
 
   private def javacErrorpath(tmp: Path) = tmp.resolve("errorpath.txt")
 
-  def customJavac(
-      sourceroot: Path,
-      targetroot: Path,
-      tmp: Path,
-      javaAtLeast17: Boolean
-  ): Path = {
+  def customJavac(sourceroot: Path, targetroot: Path, tmp: Path): Path = {
     val bin = tmp.resolve("bin")
     val javac = bin.resolve("javac")
     val java = bin.resolve("java")
@@ -51,11 +44,9 @@ object Embedded {
         |""".stripMargin.getBytes(StandardCharsets.UTF_8)
     )
     val newJavacopts = tmp.resolve("javac_newarguments")
-    val javacModuleOptions =
-      if (javaAtLeast17)
-        BuildInfo.javacModuleOptions.mkString(" ")
-      else
-        ""
+    // --add-exports flags required to access internal javac APIs from our
+    // SemanticDB plugin. Always set; Java 11+ is the supported baseline.
+    val javacModuleOptions = BuildInfo.javacModuleOptions.mkString(" ")
     val injectSemanticdbArguments = List[String](
       "java",
       s"-Dsemanticdb.errorpath=$errorpath",

scip-java/src/main/scala/com/sourcegraph/scip_java/Embedded.scala

@@ -4,7 +4,6 @@ import scala.collection.mutable
 import scala.jdk.CollectionConverters.CollectionHasAsScala
 import scala.math.Ordering.Implicits.seqOrdering
 
-import com.sourcegraph.scip_java.commands.CommentSyntax
 import moped.reporters.Input
 import moped.reporters.Position
 import org.scip_code.scip.Document
@@ -20,11 +19,10 @@ object ScipPrinters {
    */
   val sourceIndent = "  "
 
-  def printTextDocument(
-      doc: Document,
-      text: String,
-      comments: CommentSyntax = CommentSyntax.default
-  ): String = {
+  // scip-java only indexes Java and Kotlin sources, both of which use `//`.
+  private val commentSyntax = "//"
+
+  def printTextDocument(doc: Document, text: String): String = {
     val out = new mutable.StringBuilder()
     val occurrencesByLine = doc
       .getOccurrencesList
@@ -56,8 +54,6 @@ object ScipPrinters {
           }
         )
         .toMap
-    val extension = doc.getRelativePath.split("\\.").lastOption.getOrElse("")
-    val commentSyntax = comments.extensionSyntax(extension)
     val input = Input.filename(doc.getRelativePath, text)
 
     // Collect enclosing ranges from all occurrences, grouped by start/end line.
@@ -118,7 +114,7 @@ object ScipPrinters {
             (o.getRangeList.asScala.toList.map(_.toInt), o.getSymbol)
           )
         occurrences.foreach { occ =>
-          formatOccurrence(input, out, occ, line, symtab, commentSyntax)
+          formatOccurrence(input, out, occ, line, symtab)
           if ((occ.getSymbolRoles & SymbolRole.Definition_VALUE) > 0) {
             syntheticDefinitions
               .getOrElse(occ.getSymbol, Nil)
@@ -129,7 +125,6 @@ object ScipPrinters {
                   occ,
                   line,
                   symtab,
-                  commentSyntax,
                   syntheticDefinition = Some(syntheticDefinition)
                 )
               }
@@ -177,7 +172,6 @@ object ScipPrinters {
       occ: Occurrence,
       line: String,
       symtab: Map[String, SymbolInformation],
-      comment: String,
       syntheticDefinition: Option[SymbolInformation] = None
   ): Unit = {
     val pos = mopedPosition(input, occ)
@@ -199,8 +193,8 @@ object ScipPrinters {
       else
         "reference"
     val indent =
-      if (pos.startColumn + sourceIndent.length > comment.length)
-        " " * (pos.startColumn + sourceIndent.length - comment.length)
+      if (pos.startColumn + sourceIndent.length > commentSyntax.length)
+        " " * (pos.startColumn + sourceIndent.length - commentSyntax.length)
       else
         ""
     val caretCharacter =
@@ -220,7 +214,7 @@ object ScipPrinters {
     val _ = ScipSymbol.parseOrThrowExceptionIfInvalid(symbol)
 
     out
-      .append(comment)
+      .append(commentSyntax)
       .append(indent)
       .append(carets)
       .append(" ")
@@ -235,7 +229,7 @@ object ScipPrinters {
     syntheticDefinition.orElse(symtab.get(occ.getSymbol)) match {
       case Some(info) if isDefinition =>
         val prefix =
-          comment + (" " * indent.length) + (" " * carets.length) + " "
+          commentSyntax + (" " * indent.length) + (" " * carets.length) + " "
         if (!info.getDisplayName.isEmpty) {
           out
             .append(prefix)

scip-java/src/main/scala/com/sourcegraph/scip_java/ScipPrinters.scala

@@ -57,7 +57,6 @@ object BuildTool {
         .copy(
           output = index.finalOutput,
           targetroot = List(targetroot),
-          packagehub = index.packagehub,
           app = index.app
         )
         .run()

scip-java/src/main/scala/com/sourcegraph/scip_java/buildtools/BuildTool.scala

@@ -23,7 +23,7 @@ case class ClasspathEntry(
     artifactId: String,
     version: String
 ) {
-  def toPackageHubId: String = s"maven:$groupId:$artifactId:$version"
+  def mavenCoordinate: String = s"maven:$groupId:$artifactId:$version"
   def toPackageInformation: MavenPackage =
     new MavenPackage(entry, groupId, artifactId, version)
 }

scip-java/src/main/scala/com/sourcegraph/scip_java/buildtools/ClasspathEntry.scala

@@ -5,6 +5,7 @@ import java.nio.file._
 
 import scala.collection.mutable.ListBuffer
 import scala.util.Properties
+import scala.util.Try
 
 import com.sourcegraph.io.DeleteVisitor
 import com.sourcegraph.scip_java.Embedded
@@ -26,13 +27,60 @@ class GradleBuildTool(index: IndexCommand) extends BuildTool("Gradle", index) {
   }
 
   override def generateScip(): Int = {
-    BuildTool.generateScipFromTargetroot(
-      generateSemanticdb(),
-      targetroot,
-      index
-    )
+    val gradleResult = generateSemanticdb()
+    if (gradleResult.exitCode == 0) {
+      reportMissingSemanticdbOutput()
+    }
+    BuildTool.generateScipFromTargetroot(gradleResult, targetroot, index)
+  }
+
+  /**
+   * Diagnose the case where Gradle finished successfully but our SemanticDB
+   * compiler plugin never produced any `.semanticdb` files. This used to be
+   * silently rescued by a `-javaagent` fallback; now it surfaces as a clear
+   * error pointing at the two known causes.
+   */
+  private def reportMissingSemanticdbOutput(): Unit = {
+    if (containsFileWithSuffix(targetroot, ".semanticdb"))
+      return
+    if (!containsFileWithSuffix(index.workingDirectory, ".class"))
+      // Project produced no compiled JVM output — nothing to index, stay quiet.
+      return
+    index
+      .app
+      .reporter
+      .error(
+        s"""scip-java: Gradle finished successfully but produced no SemanticDB output in $targetroot.
+           |
+           |This means our SemanticDB compiler plugin was not attached to one or more JavaCompile tasks. Two known causes:
+           |
+           |  1. The 'compileOnly' configuration was already resolved before our init script ran.
+           |     Check the Gradle output above for warnings of the form:
+           |       "scip-java: failed to attach SemanticDB compiler plugin to project '<name>'"
+           |     Workaround: apply the SemanticDB plugin earlier (e.g. via a settings plugin),
+           |     or restructure the build so that 'compileOnly' is not resolved at evaluation time.
+           |
+           |  2. Another Gradle plugin is replacing the compiler arguments we add (rather than appending).
+           |     Verify with:  ./gradlew compileJava --info | grep -- '-Xplugin:semanticdb'
+           |     If '-Xplugin:semanticdb' is missing from the printed javac command, another plugin
+           |     is overwriting JavaCompile.options.compilerArgs.
+           |""".stripMargin
+      )
   }
 
+  private def containsFileWithSuffix(root: Path, suffix: String): Boolean =
+    Files.isDirectory(root) &&
+      Try {
+        val stream = Files.find(
+          root,
+          Integer.MAX_VALUE,
+          (p, attrs) =>
+            attrs.isRegularFile && p.getFileName.toString.endsWith(suffix)
+        )
+        try stream.findFirst().isPresent
+        finally stream.close()
+      }.getOrElse(false)
+
   def targetroot: Path = index.finalTargetroot(defaultTargetroot)
 
   private def defaultTargetroot: Path = Paths.get(
@@ -62,7 +110,6 @@ class GradleBuildTool(index: IndexCommand) extends BuildTool("Gradle", index) {
   }
 
   private def runCompileCommand(
-      // toolchains: GradleJavaToolchains,
       tmp: Path,
       gradleCommand: String
   ): CommandResult = {
@@ -81,27 +128,14 @@ class GradleBuildTool(index: IndexCommand) extends BuildTool("Gradle", index) {
 
     Files.walkFileTree(targetroot, new DeleteVisitor())
     val result = index.process(buildCommand, env = Map("TERM" -> "dumb"))
-    printDebugLogs(tmp)
     Embedded
       .reportUnexpectedJavacErrors(index.app.reporter, tmp)
       .getOrElse(result)
   }
 
   private def scipJavaDependencies = "scipJavaDependencies"
 
-  private def printDebugLogs(tmp: Path): Unit = {
-    val path = GradleJavaCompiler.debugPath(tmp)
-    if (index.verbose && Files.isRegularFile(path)) {
-      Files
-        .readAllLines(path)
-        .forEach { line =>
-          index.app.info(line)
-        }
-    }
-  }
-
   private def initScript(tmp: Path): Path = {
-    val agentpath = Embedded.agentJar(tmp)
     val pluginpath = Embedded.semanticdbJar(tmp)
     val gradlePluginPath = Embedded.gradlePluginJar(tmp)
     val semanticdbKotlincPath = Embedded.semanticdbKotlincJar(tmp)
@@ -122,7 +156,6 @@ class GradleBuildTool(index: IndexCommand) extends BuildTool("Gradle", index) {
          |   project.ext["semanticdbTarget"] = "$targetroot"
          |   project.ext["javacPluginJar"] = "$pluginpath"
          |   project.ext["dependenciesOut"] = "$dependenciesPath"
-         |   project.ext["javacAgentPath"] = "$agentpath"
          |   project.ext["semanticdbKotlincJar"] = "$semanticdbKotlincPath"
          |   apply plugin: SemanticdbGradlePlugin
          | }