Hints on how to get Intellij Scala Plugin to stop at breakpoints

The screenshot of the following tiny scala script shows four breakpoints set.

object WC {

  val code = """import org.apache.hadoop.conf.Configuration

// This class performs the map operation, translating raw input into the key-value

class TokenizerMapper extends Mapper[Object,Text,Text,IntWritable] {


  def sloc(str: String): Int = {

    val x: List[String] = str.split("\\n").map(_.trim).toList.filter { line =>

      line.length!=0 && !line.startsWith("import ") && !line.startsWith("/*")  && !line.startsWith("//") && !line.equals("{") && !line.equals("}") }





println (WC.sloc(WC.code))

Screen Shot 2013-11-20 at 10.32.49 AM.png
only the very last breakpoint - on the "println (WC.sloc(WC.code))" - is actually respected. The others are ignored
However, I can step through the other three lines in the debugger
I am wondering if others have discovered any "pattern" to how to get the scala debugger to respect the breakpoints. OK we know that the scala plugin is buggy - it is here a matter of trying to get the "most" out of what we have.

BTW I am using the latest IJ ULtimate 12.1.6.  (Note: this has also been posted to StackOverflow)..


the best solution is to write code in a style that is debuggable, meaning mostly one statement per line, just like in java :|
scala is very hard to debug, because you can basically have 5 expressions and 3 classes in a single line, if you want to

i rely on the repl & tests rather than debugging. on the long run, it's better anyway


Hi HOD,   thx for responding.   The interesting thing here is that it DOES step through each line with the debugger.  It just does not stop at those lines when configured as  breakpoints.  I wonder why that would be..   I would not be much in favor of "writing scala like java" approach - given the better tooling then I'd in that case just write java.


Breakpoints in your example works for regular Scala run, but not for Scala script. We will create a ticket for this problem.
For scripts it seem we don't have mapping mechanism to generated classes. It's a bug, but you still can wrap into object, which extends App and run.

Best regards,
Alexander Podkhalyuzin.


Thx Alexander.  Yes I have stopped writing scala "scripts" due to several issues in IJ with them (not just this one).  IJ -even with its various bugs wrt to scala - is still better than eclipse-based Scala IDE so I adjust my development style to work around its shortcomings.


Thanks for creating the ticket. I am going to upvote.


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