Looks like I can fix this by switching the porter stemmer with the kstemmer. I'll do some more research.

So the problem is that the porter stemmer which we use right now stems "alias" to "alia" and "aliases" to "alias". They really need to stem to the same place.

I'm going to switch us to the kstemmer. It was designed as an improvement on the porter stemmer and in my somewhat limited testing it seems better.

Change 86854 had a related patch set uploaded by Manybubbles:
Tests for places where kstem beats porter stemmer.

https://gerrit.wikimedia.org/r/86854

Switching stemmers.

Implementation: https://gerrit.wikimedia.org/r/#/c/86853/
Regression tests: https://gerrit.wikimedia.org/r/#/c/86854/

Merged.

Change 86854 merged by jenkins-bot:
Tests for places where kstem beats porter stemmer.

https://gerrit.wikimedia.org/r/86854

verified on test2wiki