Fix not processing enums in cpp-pistache-server

[mfyuce]

Defining a reusable enum as a component schema results in a class that does not include enum values. Following changes are made:

• override 'toEnumValue' in 'AbstractCppCodegen'
• modify model templates for the 'cpp-pistache-server' project

Fixes #1317

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@ravinikam (2017/07) @stkrwork (2017/07) @etherealjoy (2018/02) @MartinDelille (2018/03) @muttleyxd (2019/08)

[wing328]

@mfyuce thanks for the PR. Is it correct to say that you've tested these changes locally and it works for your use cases?

[etherealjoy]

I tried it and it seems OK.
There is a limitation still, in case an enum is part of the class it/nested inside it, is not generated.
But this can be handled later in a future PR.

[mfyuce]

Hi @wing328,

Is it correct to say that you've tested these changes locally and it works for your use cases?

Yes, I did the tests for our use cases and it is usable for us.

But, after server generation, we needed to do a bit manuel modification and then we were ok (delete all "EnumContainer"s, rename all "EnumContainer_anyOf"s to "EnumContainer").

May be @etherealjoy is telling about the same situation.

There is a limitation still, in case an enum is part of the class it/nested inside it, is not generated.
But this can be handled later in a future PR.

I checked qt server generation output and saw that the same situation is there, so, I thought it is a feature or sth...

[wing328]

CI failure not related to this change.

[wing328]

@mfyuce thanks for the PR, which has been included in the v5.1.0 release: https://twitter.com/oas_generator/status/1373636654024380423

[mfyuce]

@wing328 thanks to you and to the team for the great work!