Hocon encoder

[osipxd]

Just started to work on Hocon encoder implementation and want to make my work "transparent" to kotlinx.serialization team.
If this feature is not needed I'll stop working on it, otherwise, any comments are welcome!

Use cases

• Generate default config. For now, it is possible only to provide default config files from resources.
• Edit config from an app. This feature might be useful for apps having both text config and UI for configuration.

Essentials

• Primitives encoding
• Lists encoding
• Maps encoding
• Nested objects encoding
• Polymorphic types encoding
• useConfigNamingConvention support
• Reasonable exception messages
• Add KDoc comments

Nice to have

• encodeDefaults support
• Annotation like JsonClassDiscriminator
• Add description (origin) to config values

Closes #1609

[qwwdfsad]

Thanks! We're currently busy with an upcoming release of Kotlin and Kover, so will likely return to your PR shortly after the 9th of November.

If this feature is not needed

The feature is welcomed and it seems like at least a few people wanted that. It's good to start any development with a use-case though :)

[osipxd]

Thank you for your quick response!

It's good to start any development with a use-case though :)

Added some use-cases to the PR description.

[osipxd]

We're currently busy with an upcoming release of Kotlin and Kover, so will likely return to your PR shortly after the 9th of November.

@qwwdfsad sorry for bothering you but is there anybody who is able to review this PR?

[qwwdfsad]

The overall changes look good, thanks a lot for the effort! I have a few pretty minor comments and it will be good to go.

[qwwdfsad]

Great work, thanks for the contribution and your patience!

[sandwwraith]

Sorry if I missed that, but I don't see the test that checks that serializing an Int, List, etc. leads to a SerializationException("Value of type '${configValue.valueType()}' can't be used at the root of HOCON Config."). Can you add it, please? And for other exception cases too, if necessary.

[osipxd]

Ok, I'll add it

[sandwwraith]

It seems that work is almost finished; can you add this test (and resolve conflicts with #1795) so we can include your work in the release planned for this week?

[osipxd]

I'll try to finish it ASAP

[osipxd]

Added tests for unsupported root objects and map keys in two last commits.

[sandwwraith]

Great job, thanks for all your efforts!