Add cursor pagination desc order

[ziimakc]

New Features

Add cursor pagination desc order support

Usage:

cursor_by().asc() or cursor_by().desc()

---

Moved query builder logic inside all because it depends on sort order asc/desc

[ziimakc]

It seems more complicated then I expected, for example for the following cases

first=2,after=5,asc 6,7 is id>5 ASC
last=2,after=5,asc 9,10 is id>5 DESC + reverse result
last=2,before=5,asc 3,4 is id<5 DESC + reverse result
first=2,before=5,asc 1,2 is id<5 ASC 

first=2,after=5,desc 4,3 is id<5 DESC
last=2,after=5,desc 2,1 is id<5 ASC + reverse result
last=2,before=5,desc 7,6 is id>5 ASC + reverse result
first=2,before=5,desc 10,9 is id>5 DESC

first=2,after=5,before=9,asc 6,7 is id>5 and id<9 ASC
last=2,after=5,before=9,asc 7,8 is id>5 and id<9 DESC + reverse result
last=2,after=5,before=1,desc 3,2 is id<5 and id>1 ASC + reverse result
first=2,after=5,before=1,desc 4,3 is id<5 and id>1 DESC

We can say rules is that:

• reverse sort order in sql query when last is used
• if order reversed, reverse results
• for after cursor use > when asc is used
• for before cursor use > when desc is used

Will test it out and see how it works

[ziimakc]

Will add mock query tests a bit later Done.

[tyt2y3]

Happy new year. Thank you! This is sure a lot of effort, and it seems to be working. I am not too concerned as long as our test coverage increases! (which leads to some comments below)

[tyt2y3]

We should avoid changing existing test cases, since it shrinks our test coverage. Can you extract the common parts and make it a new test case?

[ziimakc]

I didn't change any existing tests, but duplicated all existing ones with desc order, it shows a bit incorrectly by github, I assume because names composite_keys_5 and composite_keys_5_desc and the rest of the test body except after and first replaced by before, last and desc which produces same query, but reversed results

[tyt2y3]

Oh thanks! Got it now

[tyt2y3]

Likewise, it's better to test both before and after separately.

[ziimakc]

Same as my previous comment, it's a copy of cursor_by_many named as cursor_by_many_desc, no tests were removed or changed except additions like .apply_limit().apply_order_by().apply_filters() because filters applied when we call all()

[github-actions]

🎉 Released In 0.12.11 🎉

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