Introduce version() which disables memory-greedy unittests

[denizzzka]

Adds ability to run unittests on systems in which there are <= 128Kb of the RAM

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[dkorpel]

It needs to be documented what this version identifier means exactly.

[denizzzka]

I'm havent find appropriate place for the description

Also, I see self described names like DRuntime_Use_Libunwind. Maybe someone can suggest a similar self-describing name for this version?

[dkorpel]

I think the name is good, but consider someone encountering the version identifier a few years down the line. They will search for the codebase for the identifier and find only a few uses, but no explanation and no tests. Nowhere is the version set, so a reasonable conclusion is that's it's a relic for some old hardware that's no longer relevant, so it can be removed.

I'm constantly finding relics myself and questioning what they're for. A little explanation goes a long way in helping future contributors.

[dkorpel]

I'm fine with merging this because it's harmless and you clearly have a use case for it, but do note that there's little stopping someone from adding new tests using lots of RAM, or removing the version in the future.

[denizzzka]

@dkorpel

but do note that there's little stopping someone from adding new tests using lots of RAM, or removing the version in the future.

Sure, but when I found it I can add this dedicated version to such tests too