Fix error adding first product_feature (when no product feature exists)

[robinbittner]

When creating the first product_feature in the database, the response from PrestaShop API is OK, but contains an empty "position" element: <position></position>

This raises "object null reference error" in PrestaSharpDeserializer, because "position" element is expected to contain any non-empty INT value. The error does not appear when creating 2nd, 3rd, etc. product_feature.

[mowcixo]

Hello @robinbittner, thanks for the PR. As it bug is produced by a bug in PrestaShop, I don't think we should address it, in fact I've reported this bug in the PrestaShop repository time ago as you can see in https://github.com/PrestaShop/PrestaShop/issues/14439

We are going to think about that, maybe we should address empty values in all deserialization process.

[robinbittner]

Hi, I know it is a bug in PrestaShop. I use latest PrestaShop 1.7.6.1 and is not corrected yet. But users of PrestaSharp do not know it and for them using PrestaSharp can be tricky. From my point of view, everthing that makes PrestaSharp more stable is valuable.

But I accept your point of view as well,

[mowcixo]

Totally true. Can you review then, If it could be possible to have another bugs in PrestaSharpDeserializer.cs related to parsing primitive types and if there are, use this PR to fix it?

[robinbittner]

sure, I will be glad to contribute. This week I was debugging PrestaSharpDeserializer.cs several times, and I did not discover any other error. Next 2 months I will be using your PrestaSharp very intensively, because I migrate winery eshop to PrestaShop. If I find an error, I will create PR. At the moment I have some small improvements (few code lines) and I will create PR for them.

[mowcixo]

That's great. Just try to make the PR as atomic as you can, avoiding use the same PR for multiple unrelated things.

Merging this.

[robinbittner]

ok, I will do small PR - they are better to review and merge.