fix: added check for null and undefined strings

[milenkovyua]

I found a bug, where passing TVP with varchar column as parameter, filled with null values, leads to recording the data in SQL server, with "null", instead of NULL. This is caused because of the default behavior of V8, converting JavaScript values, to strings in C++, where null is converted into "null" and undefined is converted into "undefined".

This pull request is adding check for IsNull and IsUndefined on v8::Localv8::Value and fix this issue. If you need me, I can prepare an isolated environment, describing this behavior.

[milenkovyua]

Do you want to discuss the changes? I am not very familiar with C++, so it probably could be written in a better way.

[TimelordUK]

Thanks very much for the fix - much appreciated I need to check to see if the same problem exists elsewhere in that file and write a few tests. Will report back shortly - and will pull your change. thanks a lot.

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On Thu, 21 Jan 2021 at 19:33, Yuliyan Milenkov ***@***.***> wrote: Do you want to discuss the changes? I am not very familiar with C++, so it probably could be written in a better way. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#194 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABXWJG2RWQGWLT625Y54P6TS3B6PNANCNFSM4WHQW7TA> .

[TimelordUK]

I will be releasing this soon 2.0.11 - thanks for bringing this to our attention, in actual fact you found a general problem managing any bulk inset vector including nulls, in case of buffers actually causes a fatal crash.

I have added test cases and fixed the other types so hopefully this will sort things out.

thanks again