Update `SpringBootContextLoader` so that when possible the
`SpringApplication` remains in control of creating the `Environment`
instance.
Prior to this commit, we would always create the `Environment` in the
`SpringBootContextLoader` and then call `setEnvironment` on the
`SpringApplication`. This meant that the `ApplicationEnvironment`
classes were not used and that `isCustomEnvironment` was set to `true`
so no conversion was applied.
With the updated code, an `ApplicationListener` is used to mutate the
`Environment` instance and add the required test property sources.
Fixes gh-29169
Refine the logic introduced in 64270eca to use a side-effect free
Environment implementation rather than converting the Environment early.
Early conversion can cause condition evaluation issues if
`src/test/resources/application.properties` files are bound to the
`SpringApplication`. Specifically the `spring.main.web-application-type`
property can change the `Environment` type which must happen before
conditions are evaluated.
Fixes gh-29169
This commit aligns `SpringBootTest`s to also use `ApplicationEnvironment`
instead of `StandardEnvironment`. This prevents the side-effect of active
profiles from `@ActiveProfiles` from being added to the environment when
doGetActiveProfiles is called. In this case, calling `addActiveProfiles()`
in the environment post processor would result in `@ActiveProfiles` being
added to the environment first, resulting in the wrong order.
The additional call to `setActiveProfiles()` is also not necessary when using
ApplicationEnvironment because that call was put in place to prevent the side-effect
which `ApplicationEnvironment` does not have.
Fixes gh-28530
Change the order of `DataSourceScriptDatabaseInitializerDetector` so
that it always runs last. This update allows script initialization to
be combined with a high-level migration tool such as Flyway.
Closes gh-26692
