adt: split interval tree by right endpoint on matched left endpoints

[redwrasse]

Splits interval trees by right endpoint on matched left endpoints, to improve exact interval matching performance.
This addresses the issue: #19769

[k8s-ci-robot]

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[k8s-ci-robot]

Hi @redwrasse. Thanks for your PR.

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[serathius]

I was not able to find a proper tests for the Find method. Would you mind preparing some tests before we change the logic?

[redwrasse]

Yes,I'll add tests. I was thinking of just adding assertions on the Find operation to the existing TestIntervalTreeRandom here as say

	for ab := range ivs {
		for xy := range ivs {
			v := xy.x + int64(rand.Intn(int(xy.y-xy.x)))
			require.NotEmptyf(t, ivt.Stab(NewInt64Point(v)), "expected %v stab non-zero for [%+v)", v, xy)
			require.Truef(t, ivt.Intersects(NewInt64Point(v)), "did not get %d as expected for [%+v)", v, xy)
		}
		iv := ivt.Find(NewInt64Interval(ab.x, ab.y))
		assert.NotNil(t, iv)
		assert.Equal(t, NewInt64Interval(ab.x, ab.y), iv.Ivl)
		assert.Truef(t, ivt.Delete(NewInt64Interval(ab.x, ab.y)), "did not delete %v as expected", ab)
		delete(ivs, ab)
	}

In addition I can add a separate dedicated unit test for the Find op to test edge cases if that's warranted.

[serathius]

Thanks, please send a separate PR. It should be much easier to review and merge a new tests that don't change the logic.

[redwrasse]

@serathius opened up a separate MR with IntervalTree.Find() tests: #19801

[serathius]

Please include benchmark from #19769 in the PR.

[redwrasse]

Please include benchmark from #19769 in the PR.

Will do, I'll investigate using benchstats.