Add precise swipe actions for swipes from a start to an end point

[steviki]

This PR implements and fixes #674.

Introduces new swipe actions, that take a starPoint and an endPoint and perform a swipe along those points via two new public functions:

grey_swipeFastFromStartToEndPoint(CGPoint startPoint, CGPoint endPoint);
grey_swipeSlowFromStartToEndPoint(CGPoint startPoint, CGPoint endPoint);

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This is done via the new GREYPreciseSwipeAction class, that is implemented similar to GREYSwipeAction, but instead of taking a direction, duration and startPercents, the precise swipe action takes a startPoint, endPoint and duration.

When performing this action, a swipe with a single touch is executed that follows the path from the startPoint to the endPoint in the time of the given duration.

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[steviki]

I signed it!

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CLAs look good, thanks!

[tirodkar]

Is the startpoint based on a point in the whole screen or within the matched view?

[steviki]

It is based on the whole screen currently.
But it might make more sense to base this on the origin of the matched view.
I will change that and clarify in the documentation.

[tirodkar]

@steviki any updates on this?

[steviki]

@tirodkar Yes, the change to use points based on the origin of the matched view landed in 0380dbb.
So this PR is good to go from my side.

Please let me know if there are any questions left.

[tirodkar]

QQ - isn't this the same as scroll amount? Ir are you trying to do from any point to another?

[steviki]

It doesn't seem to be the same as scrolling in a direction with a given amount, as the scroll amount action only allows scrolling in a GREYDirection (which is restricted to left, right, up, and down) and not any arbitrary direction. While scrolling from a specific point to another point allows to scroll in any direction without restriction.

[steviki]

Just wanted to check in on the status here.
I'd love to get this PR merged, so let me know if there is anything left for me to take care of.
Thank you!

[khandpur]

It looks like you want precision here. Is there a reason for not using scroll API which is much more precise than swipe?

[steviki]

Is there a reason for not using scroll API which is much more precise than swipe?

@khandpur I'm not quite sure if I understand your question correctly, so please correct me if I'm wrong.
If you are referring to GREYScrollAction, then the reason is that it doesn't allow scrolling from one point to another in any arbitrary directions, but only in predefined GREYDirections.

[khandpur]

Could you add some tests for the new action?

[steviki]

@khandpur Sorry for the long delay, but I've now added unit and functional tests for the precise swipe actions.
Looking forward to your feedback!

[steviki]

@khandpur Just wanted to ping to check on the status of this PR. I would really appreciated if you could have another look at this PR and consider merging it. Let me know if there are any questions!

[khandpur]

Mostly minor nits. Would be great if you could wrap header files with Nullability macros (NS_ASSUME_NONNULL_BEGIN / END) as well. Once done, I'll merge the changes. Thanks!

[steviki]

Thanks for the review @khandpur.
I addressed all your feedback, and fixed the code style nits, adjusted the wrong indentations, added nullability macros to GREYPreciseSwipeAction.h, and also rebased this branch to the latest master.

[khandpur]

@tirodkar PTAL and merge if it looks good.

[khandpur]

And thank you Stefan for adding this feature request!

[steviki]

Thank you for reviewing this PR and getting it merged! I really appreciate it.

@tirodkar I also addressed your review feedback now and fixed the typo.

[khandpur]

@tirodkar I've restarted the CI. Could we merge this and make it available in earlgrey 2?

[steipete]

Hi! Are there any blockers left for merging this?