https://pharo.fogbugz.com/f/cases/19661/When-coding-in-the-debugger-I-get-an... Then I got a really strange problem when I was doing the counter execise using the debugger. create a Test Case TestCase subclass: #CounterTest instanceVariableNames: '' classVariableNames: '' package: 'Counter' - add testValueAtCreation self assert: (Counter new count: 10) count equals: 10 - ok to define classes - define count: in the class Counter - count: anInteger count := anInteger - Declare instance variable count NOW problem Instance of class did not understand count - ok to define it => Instance of IRMethod do not understand sourceNodeExecuted HAnging around instances ========== Then if I remove the Counter class and relaunch the tests I get Instance of anObsoleteCounter did not understandâ¦.