Add support checking same security matchers

[franticticktick]

Closes gh-15982

[jzheaux]

Thanks, @franticticktick! I've left my feedback inline.

Also, if you want to add #16213 to this PR as a separate commit, I think that makes sense.

[jzheaux]

@franticticktick, given #16249, I'd like to change my recommendation as that ticket would remove the notion of "after-any" unreachability. Thus, the idea of having some kind of validation reporter may be more brittle than I had first considered (since one of the handlers could be immediately deprecated).

Instead, I think a new implementation of FilterChainValidator would be better. In this way, the XML validation remains unaffected. I think WebSecurityFilterChainValidator would be a good name. Do you have any concerns about that approach?

[franticticktick]

@jzheaux maybe it makes sense to open a new ticket? In this issue, I can fix bugs in DefaultFilterChainValidator, and add equals and hashCode to OrRequestMatcher in a separate commit. In general, i can start working on the WebSecurityFilterChainValidator in the 16213.

[jzheaux]

Good points, @franticticktick.

My thought is that the improvements to DefaultFilterChainValidator are more a polish and doesn't necessarily require a ticket. So perhaps that simply moves to a separate commit in this PR.

Then, there should be another commit that solves #15982 which includes improving the matchers as well as adding the check to WebSecurityFilterChainValidator. To that end, I've pushed a commit to add WebSecurityFilterChainValidator already so this commit will only be focused on adding the feature.

How does that sound?

[franticticktick]

@jzheaux thanks for the recommendations, I added tests for WebSecurityFilterChainValidator and a new exception type UnreachableFilterChainException.

[jzheaux]

Thanks for the update, @franticticktick! I've left feedback inline.

[jzheaux]

Thanks for the update, @franticticktick, it looks good.

My apologies there is one item I forgot, please see my inline comment for details.

[franticticktick]

@jzheaux thanks for your feedback, everything is done.

[franticticktick]

@jzheaux could you please review the third commit? It solves 16213

[jzheaux]

Thanks, @franticticktick. Another very helpful PR!