REPL format stack trace prefix of exception

Author: som-snytt

compiler/src/dotty/tools/repl/Rendering.scala

@@ -11,7 +11,7 @@ import dotc.core.Denotations.Denotation
 import dotc.core.Flags
 import dotc.core.Flags._
 import dotc.core.Symbols.{Symbol, defn}
-import dotc.core.StdNames.str
+import dotc.core.StdNames.{nme, str}
 import dotc.core.NameOps._
 import dotc.printing.ReplPrinter
 import dotc.reporting.{MessageRendering, Message, Diagnostic}
@@ -120,20 +120,22 @@ private[repl] class Rendering(parentClassLoader: Option[ClassLoader] = None) {
       if (d.symbol.is(Flags.Lazy)) Some(infoDiagnostic(dcl, d))
       else valueOf(d.symbol).map(value => infoDiagnostic(s"$dcl = $value", d))
     }
-    catch { case ex: InvocationTargetException => Some(infoDiagnostic(renderError(ex), d)) }
+    catch { case ex: InvocationTargetException => Some(infoDiagnostic(renderError(ex, d), d)) }
   }
 
-  /** Render the stack trace of the underlying exception */
-  private def renderError(ex: InvocationTargetException): String = {
-    val cause = ex.getCause match {
+  /** Render the stack trace of the underlying exception. */
+  private def renderError(ite: InvocationTargetException, d: Denotation)(using Context): String =
+    import dotty.tools.dotc.util.StackTraceOps._
+    val cause = ite.getCause match {
       case ex: ExceptionInInitializerError => ex.getCause
       case ex => ex
     }
-    val sw = new StringWriter()
-    val pw = new PrintWriter(sw)
-    cause.printStackTrace(pw)
-    sw.toString
-  }
+    def isWrapperCode(ste: StackTraceElement) =
+      ste.getClassName == d.symbol.owner.name.show
+      && (ste.getMethodName == nme.STATIC_CONSTRUCTOR.show || ste.getMethodName == nme.CONSTRUCTOR.show)
+
+    cause.formatStackTracePrefix(!isWrapperCode(_))
+  end renderError
 
   private def infoDiagnostic(msg: String, d: Denotation)(using Context): Diagnostic =
     new Diagnostic.Info(msg, d.symbol.sourcePos)