[mkurz]

Backport of #898 to 8.x. Unlike on main, this doesn't depend on the plugin fix (#895), because on 8.x the plugin still swallows the enhancer error for the missing models package.

The docs code samples were outdated and did not compile anymore:

• MyServerConfigStartup used io.ebean.config.ServerConfig, which doesn't exist anymore. ServerConfigStartup.onStart takes a DatabaseBuilder now.
• The transaction samples used the io.ebean.Ebean class, which doesn't exist anymore either. They now use io.ebean.DB, and the "traditional" sample uses a try-with-resources Transaction (DB has no commitTransaction()/endTransaction()). The text also mentioned TxRunnable and TxCallable, which are gone as well.

This went unnoticed, because CI only ran validateCode for the docs, which never compiles the samples. The docs job now also runs the docs tests, like e.g. twirl and play-slick do. For that, the docs build now enhances the models of its test sources (where the samples live); before, it only set Test / playEbeanModels, without actually wiring up the enhancement for Test.

Also, the docs now point out that a ServerConfigStartup has to be covered by an ebean. config line: Play Ebean registers the configured classes with Ebean explicitly, which disables Ebean's classpath scanning, so any other ServerConfigStartup gets silently ignored. That's what happened in #355.

Testing

cd docs && sbt ++2.13.x "validateCode; test" and ++3.x: all 4 JavaEbeanTest tests pass.

[mergify]

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