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[GBR-613]

Fixing issue #230

[robhagemans]

Thanks for fixing this bug! I found a simpler approach (the main problem was that from_line was calculated but then ignored, along with the initial setting of last_stored to None).

I've taken your commit fixing PyLint warnings and will merge all or part of it - some things PyLint complains about are conscious coding style choices, but not all of it.

[GBR-613]

@robhagemans I remember I tried to implement "from_line based" approach and found a scenario when the behavior was like I would expect yet different from GWBASIC, and ended up with this one.
Unfortunately I don't remember that scenario. If I will succeed to reproduce I will report.

[robhagemans]

Thanks! Let me know if you find the scenario. One thing I noticed was that after the change , AUTO . if used on an empty program buffer would start at line number 10, whereas this should be line number 0. The change in initial value for last_stored deals with this, without AFAICS undesired side effects.

Actually I still need to create a test for the latter scenario.