Suppress tracing while tracing

[kuzuk]

Feature request: in the code handling tracers, suppress 'tracing while tracing'. That is: tracing instrumentation triggered while already tracing should not be followed on.

E.g. when entering a method, toString or other methods can often be called to serialize the parameter list for logging. This toString() call and methods it calls should not in turn cause tracing.

I propose setting this suppression on always, without option to disable it because I see no use-case where 'tracing while tracing' makes sense.

[snorbi07]

Hi @kuzuk,
This is definitely a bug, so I agree that it needs to be the "default" behavior. The issue #44 will improve the situation of this as well.
This might be more of an issue with the tracer runtime (https://github.com/GoodGrind/ghostwriter-tracer) though. Anyways, I have to analyze how to tackle this the best way. Currently, at compile time we don't know whether a method call leads to already "traced" code or not.