Use MatchPhraseQuery for bleve code search

[jpraet]

Fix regression from #32210 which unintentionally changed the search mode for bleve from MatchPhraseQuery to MatchQuery.

On the main branch, meanwhile with #33590 a "literal code search" mode (by using quotes) was implemented as workaround for this unexpected code search behavior. Maybe that feature needs some redesign as it turns out to have been caused by a regression.

But this PR at least already fixes the regression for 1.23.x

[jpraet]

The test fails because the default behavior for bleve now differs from elasticsearch.

[darren]

use MatchPhraseQuery would be too strict for cases when search for some words that I don't remember exactly, for the case I raised in #33588, if switch to MatchPhraseQuery searching for swagger template returns no result while the second hit is valid in my opinion:

[jpraet]

My instance was recently upgraded from 1.22 and 1.23 and many users complain about the code search returning way too many irrelevant results in the new version. In 1.22 MatchPhraseQuery was used for bleve. In 1.23 it now uses MatchQuery without any option for the user to switch it back to MatchPhraseQuery.

I don't know what the best course of action is. Maybe your PR #33590 can be backported to 1.23.

[lunny]

#33590

Maybe we can backport it after

My instance was recently upgraded from 1.22 and 1.23 and many users complain about the code search returning way too many irrelevant results in the new version. In 1.22 MatchPhraseQuery was used for bleve. In 1.23 it now uses MatchQuery without any option for the user to switch it back to MatchPhraseQuery.

I don't know what the best course of action is. Maybe your PR #33590 can be backported to 1.23.

Maybe it's better to backport #33590 ?

[jpraet]

I feel like returning ~200 matches when searching for swaggerParameterBodies is probably worse than not returning a match when searching for swagger template. But I agree both should work ideally.

GitHub search returns a single match for swaggerParameterBodies, without requiring quotes around it.
If you search for swagger parameter bodies you get 2 matches and not 200 😄.

So as I said: I don't know what the right approach is, but bleve code search feels broken in 1.23.