Merge a1db6902aa into 8bcc6ae420

testing/src/main/scala/sbt/JUnitXmlTestsListener.scala

@@ -28,6 +28,7 @@ import testing.{
 }
 import util.Logger
 import sbt.protocol.testing.TestResult
+import sbt.internal.worker1.ForkTestMain
 
 /**
  * Companion object for JUnitXmlTestsListener that caches the hostname lazily.
@@ -159,25 +160,36 @@ class JUnitXmlTestsListener(val targetDir: File, legacyTestReport: Boolean, logg
             } time={(e.duration() / 1000.0).toString}>
                       {
               val trace: String = if (e.throwable.isDefined) {
-                val stringWriter = new StringWriter()
-                val writer = new PrintWriter(stringWriter)
-                e.throwable.get.printStackTrace(writer)
-                writer.flush()
-                stringWriter.toString
+                e.throwable.get match {
+                  case fe: ForkTestMain.ForkError =>
+                    formatForkErrorTrace(fe)
+                  case other =>
+                    val stringWriter = new StringWriter()
+                    val writer = new PrintWriter(stringWriter)
+                    other.printStackTrace(writer)
+                    writer.flush()
+                    stringWriter.toString
+                }
               } else {
                 ""
               }
+              val (exType, exMessage) = e.throwable match {
+                case t if t.isDefined =>
+                  t.get match {
+                    case fe: ForkTestMain.ForkError =>
+                      (fe.getOriginalName, fe.getOriginalMessage)
+                    case other =>
+                      (other.getClass.getName, other.getMessage)
+                  }
+                case _ => ("", "")
+              }
               e.status match {
                 case TStatus.Error if (e.throwable.isDefined) =>
-                  <error message={e.throwable.get.getMessage} type={
-                    e.throwable.get.getClass.getName
-                  }>{trace}</error>
+                  <error message={exMessage} type={exType}>{trace}</error>
                 case TStatus.Error =>
                   <error message={"No Exception or message provided"}/>
                 case TStatus.Failure if (e.throwable.isDefined) =>
-                  <failure message={e.throwable.get.getMessage} type={
-                    e.throwable.get.getClass.getName
-                  }>{trace}</failure>
+                  <failure message={exMessage} type={exType}>{trace}</failure>
                 case TStatus.Failure =>
                   <failure message={"No Exception or message provided"}/>
                 case TStatus.Ignored | TStatus.Skipped | TStatus.Pending =>
@@ -262,6 +274,36 @@ class JUnitXmlTestsListener(val targetDir: File, legacyTestReport: Boolean, logg
     writeSuite()
   }
 
+  /**
+   * Formats a ForkError stacktrace using the original exception name instead of
+   * the ForkError wrapper class. This fixes the JUnit XML report showing
+   * `sbt.internal.worker1.ForkTestMain$ForkError` instead of the actual exception type.
+   * See https://github.com/sbt/sbt/issues/1469
+   */
+  private def formatForkErrorTrace(fe: ForkTestMain.ForkError): String = {
+    val sb = new StringBuilder
+    sb.append(fe.getOriginalName)
+    val msg = fe.getOriginalMessage
+    if (msg != null) sb.append(": ").append(msg)
+    sb.append('\n')
+    for (elem <- fe.getStackTrace)
+      sb.append("\tat ").append(elem).append('\n')
+    val cause = fe.getCause
+    if (cause != null) {
+      cause match {
+        case feCause: ForkTestMain.ForkError =>
+          sb.append("Caused by: ").append(formatForkErrorTrace(feCause))
+        case other =>
+          val stringWriter = new StringWriter()
+          val writer = new PrintWriter(stringWriter)
+          other.printStackTrace(writer)
+          writer.flush()
+          sb.append("Caused by: ").append(stringWriter.toString)
+      }
+    }
+    sb.toString
+  }
+
   // Here we normalize the name to ensure that it's a nicer filename, rather than
   // contort the user into not using spaces.
   private def normalizeName(s: String) = s.replaceAll("""\s+""", "-")

testing/src/test/scala/sbt/JUnitXmlTestsListenerSpec.scala

@@ -15,7 +15,9 @@ import testing.{ Event as TEvent, OptionalThrowable, Status as TStatus, TestSele
 import util.{ AbstractLogger, Level, ControlEvent, LogEvent }
 import sbt.io.IO
 import sbt.protocol.testing.TestResult
+import sbt.internal.worker1.ForkTestMain
 import verify.BasicTestSuite
+import scala.xml.XML
 
 object JUnitXmlTestsListenerSpec extends BasicTestSuite:
 
@@ -88,4 +90,61 @@ object JUnitXmlTestsListenerSpec extends BasicTestSuite:
       val xmlFile = new File(tempDir, "TEST-TestSuite.xml")
       assert(xmlFile.exists(), "XML file should be created even when logger is null")
 
+  test("JUnit XML report should use original exception type for forked test failures"):
+    val tempDir = File.createTempFile("junit-test", "")
+    tempDir.delete()
+    tempDir.mkdirs()
+    try
+      val listener = new JUnitXmlTestsListener(tempDir, false, null)
+      listener.doInit()
+      listener.startGroup("TestSuite")
+
+      // Simulate a forked test failure: the original NullPointerException gets
+      // wrapped in ForkError during serialization across the forked JVM boundary.
+      val originalException = new NullPointerException("something was null")
+      originalException.setStackTrace(
+        Array(new StackTraceElement("com.example.MyTest", "testFoo", "MyTest.java", 42))
+      )
+      val forkError = new ForkTestMain.ForkError(originalException)
+
+      val testEvent = new TEvent:
+        def fullyQualifiedName = "TestSuite.testFoo"
+        def duration() = 100L
+        def status = TStatus.Failure
+        def fingerprint = null
+        def selector = new TestSelector("testFoo")
+        def throwable = new OptionalThrowable(forkError)
+
+      listener.testEvent(sbt.TestEvent(Seq(testEvent)))
+      listener.endGroup("TestSuite", TestResult.Failed)
+
+      val xmlFile = new File(tempDir, "TEST-TestSuite.xml")
+      assert(xmlFile.exists(), "XML file should be created")
+      val xml = XML.loadFile(xmlFile)
+      val failureNodes = xml \\ "failure"
+      assert(failureNodes.nonEmpty, "Should have a failure element")
+      val failureType = (failureNodes.head \ "@type").text
+      val failureMessage = (failureNodes.head \ "@message").text
+      assert(
+        failureType == "java.lang.NullPointerException",
+        s"Expected type 'java.lang.NullPointerException' but got '$failureType'"
+      )
+      assert(
+        failureMessage == "something was null",
+        s"Expected message 'something was null' but got '$failureMessage'"
+      )
+      val traceText = failureNodes.head.text
+      assert(
+        traceText.contains("java.lang.NullPointerException"),
+        s"Stacktrace should contain original exception name, got: $traceText"
+      )
+      assert(
+        !traceText.contains("ForkError"),
+        s"Stacktrace should not contain ForkError, got: $traceText"
+      )
+    finally
+      if tempDir.exists() then
+        tempDir.listFiles().foreach(_.delete())
+        tempDir.delete()
+
 end JUnitXmlTestsListenerSpec

worker/src/main/java/sbt/internal/worker1/ForkTestMain.java

@@ -158,6 +158,16 @@ public class ForkTestMain {
       return originalName + ": " + originalMessage;
     }
 
+    /** Returns the fully qualified class name of the original exception. */
+    public String getOriginalName() {
+      return originalName;
+    }
+
+    /** Returns the original exception message (without the class name prefix). */
+    public String getOriginalMessage() {
+      return originalMessage;
+    }
+
     public Exception getCause() {
       return cause1;
     }