fix: caching: resetting global static variable for each run, fixed ac…

[gethrok]

Hello,

I think I have identified bug where enabling/disabling the cache was actually inverted... You have variable isStandardFunctionCacheDisabled = false;
and then you call
cacheFunctionCall(isStandardFunctionCacheDisabled, env, function, result);

But this method has Boolean shouldCache

private static void cacheFunctionCall(
        Boolean shouldCache,
        Environment env,
        Expr.FunctionCall function,
        Object result
    )

So if you call the method with isStandardFunctionCacheDisabled=false, it actually says shouldCache = false, therefore the caching is disabled. I would honestly rename it, I can see where this bug could come from :D Quickfix I inverted the boolean value on calling the method.

2. Because the variable isStandardFunctionCacheDisabled is static, disabling or enabling the cache in the same transaction in single call will influence calling Evaluator in other places, therefore for each evaluate I am now explicitly enabling/disabling the caching.
   I was not sure if we should also reset the cache when it gets disabled or not, that I will leave open for now.