ICU-22848 Add test for rbbi rule builder failure.

[FrankYFTang]

Checklist

• [X] Required: Issue filed: https://unicode-org.atlassian.net/browse/ICU-22848
• [X] Required: The PR title must be prefixed with a JIRA Issue number.
• [X] Required: The PR description must include the link to the Jira Issue, for example by completing the URL in the first checklist item
• [X] Required: Each commit message must be prefixed with a JIRA Issue number.
• [ ] Issue accepted (done by Technical Committee after discussion)
• [X] Tests included, if applicable
• [ ] API docs and/or User Guide docs changed or added, if applicable

[FrankYFTang]

@aheninger could you take a look at the test case I added. It is now hang. I think it is super slow

[aheninger]

Looks like the state table builder is running in exponential time on the number of trailing dots in the test pattern, ".*X..................;"

This is deep in the guts of the dragon book state table construction algorithm. I doubt there is an easy fix - the algorithm is tricky and hard to fully understand.

I recommend just leaving this as a known issue. It's not a problem in actual real break rules.

[jira-pull-request-webhook[bot]]

Notice: the branch changed across the force-push!

• icu4c/source/test/intltest/rbbitst.cpp is different

View Diff Across Force-Push

~ Your Friendly Jira-GitHub PR Checker Bot

[jira-pull-request-webhook[bot]]

Notice: the branch changed across the force-push!

• icu4c/source/test/intltest/rbbitst.cpp is different

View Diff Across Force-Push

~ Your Friendly Jira-GitHub PR Checker Bot