[JvmModelGenerator] No Debug Trace Region created for Method as a whole

Consider following (Xtend) code

package xxxxx

class Foo {
	
	def void foo1() {
		foo2
 		println("bar")
	}
	
	def void foo2() {
		
	}
	
	def static void main(String[] args) {
		new Foo().foo1
	}
	
}

when debugging inside foo1 and doing a step into foo2 (which is an empty method)
then you will get following situation

as you can see the (closing) bracket in foo2 gets labled as line: not available

this is caused by how we create the trace regions

  [18[public [19,20[void]20,19] [21[foo2]21]() {                                                               | 	}]18]
  }]18]   

18:   198-024     DebugTraceBasedRegion -> LocationData[79,23] {
19:   205-004       DebugTraceBasedRegion -> LocationData[83,4] {
20:   205-004         DebugTraceBasedRegion -> LocationData[83,4]
19:                 }
21:   210-004       DebugTraceBasedRegion -> LocationData[88,4]
18:     

as you can see e.g. 18 is not marked as "Debug" (letter D after debug region)

if i have a look at the source code

org.eclipse.xtext.xbase.compiler.TreeAppendableUtil.traceWithComments(ITreeAppendable, EObject)

called from org.eclipse.xtext.xbase.compiler.JvmModelGenerator.generateMembersInBody(JvmDeclaredType, ITreeAppendable, GeneratorConfig)

i can see that org.eclipse.xtext.xbase.compiler.output.TreeAppendable.trace is called with useForDebugging=false

do i overlook something?

@svenefftinge @spoenemann @szarnekow can you give some hints

Start in org.eclipse.xtext.xbase.compiler.TreeAppendableUtil.traceWithComments(ITreeAppendable, EObject), following its call from JvmModelGenerator.generateMembersInBody and the TreeAppendable.trace invocation. Compare the generated trace regions for an empty foo2 method, and consider the issue resolved when the method as a whole receives a debug trace region and its closing bracket no longer shows “line: not available”.