Defaulting to ignoreSelfIntersections: false changes behavior of a number of Turf methods in v7

[pm0u]

Introduced in #2033

Defaulting to include self intersections in the @turf/line-intersect module has introduced breaking changes to a number of consuming modules as well as creating unexpected behaviors within those modules. Previously, I believe this algorithm did not / was not able to check for self intersections however now it does by default.

Examples

6.5.0
7.1.0 (includes sweepline module example)

Related issues

#2707
#2700
#2633
#2585

[pm0u]

While booleanIntersects (and others) can be worked around by adding an explicit { ignoreSelfIntersections: true }, some methods such as booleanCrosses do not expose this option and do not explicitly exclude self intersections themselves essentially rendering them broken (I do not believe the intention of crosses would be that when comparing two geometries, return true if one of the geometries crosses itself)

[smallsaucepan]

Thanks for pulling this together @pm0u. We're taking a look now.

[pm0u]

@smallsaucepan - thanks, happy to help with a PR if desired but I think where it stands now there are still some decisions to be made around how to handle this change before I could know where to go with that. let me know if I can help

[smallsaucepan]

Hi @pm0u. The current plan is to revert Turf to the ignore behaviour of 6.5.0 - across the board. These look to be undocumented breaking changes that we should fix as soon as possible.

Have created discussion #2728 to work through the details of a PR. Are you in a position to join in over there?

[smallsaucepan]

Hi @pm0u. Looks like discussion over at #2728 has concluded. Maintainers have agreed we should revert ignoreSelfIntersections behaviour to 6.5.0. Which I think means setting ignoreSelfIntersections default value to true wherever it appears in the current API.

Would you like to prepare a PR for this?