Harden IDE: Survive duplicate package and object

Author: odersky

compiler/src/dotty/tools/dotc/core/SymbolLoaders.scala

@@ -70,19 +70,19 @@ object SymbolLoaders {
       // offer a setting to resolve the conflict one way or the other.
       // This was motivated by the desire to use YourKit probes, which
       // require yjp.jar at runtime. See SI-2089.
-      if (ctx.settings.YtermConflict.isDefault)
-        throw new TypeError(
-          i"""$owner contains object and package with same name: $pname
-             |one of them needs to be removed from classpath""")
-      else if (ctx.settings.YtermConflict.value == "package") {
+      if (ctx.settings.YtermConflict.value == "package" || ctx.mode.is(Mode.Interactive)) {
         ctx.warning(
           s"Resolving package/object name conflict in favor of package ${preExisting.fullName}. The object will be inaccessible.")
         owner.asClass.delete(preExisting)
-      } else {
+      } else if (ctx.settings.YtermConflict.value == "object") {
         ctx.warning(
           s"Resolving package/object name conflict in favor of object ${preExisting.fullName}.  The package will be inaccessible.")
         return NoSymbol
       }
+      else
+        throw new TypeError(
+          i"""$owner contains object and package with same name: $pname
+             |one of them needs to be removed from classpath""")
     }
     ctx.newModuleSymbol(owner, pname, PackageCreationFlags, PackageCreationFlags,
       completer).entered