As the DSL internally calls ResultActions.andExpect, this is done with a trick where a synthetic ResultActions is provided at top level which stores each ResultMatcher in a mutable list. Once the DSL usage is done, the top level DSL andExpectAll turns that list into a vararg passed down to the actual actions.andExpectAll.
Closes gh-27317
Comment From: simonbasle
oops I've overlooked the documentation deliverable mentioned in gh-27317 😞 will do a follow-up