[Bug] SH_T Swap-hands action produces extra tap depending on timing

[ilikeheaps]

I have r key mirrored to i. Quick SH_T(KC_SPC) + r combination results in i while doing it slowly results in i as expected. Logs below contain both cases in order.

ilikeheaps:plyboard:1: ---- action_exec: start -----
ilikeheaps:plyboard:1: EVENT: 0305d(21482)
ilikeheaps:plyboard:1: Tapping: Start(Press tap key).
ilikeheaps:plyboard:1: TAPPING_KEY=0305d(21482):0 
ilikeheaps:plyboard:1: processed: 0305d(21482):0 
ilikeheaps:plyboard:1: 
ilikeheaps:plyboard:1: 
ilikeheaps:plyboard:1: ---- action_exec: start -----
ilikeheaps:plyboard:1: EVENT: 0102d(21553)
ilikeheaps:plyboard:1: waiting_buffer_enq: { [7]=0602d(21553):0  }
ilikeheaps:plyboard:1: ---- action_exec: process waiting_buffer -----
ilikeheaps:plyboard:1: 
ilikeheaps:plyboard:1: 
ilikeheaps:plyboard:1: ---- action_exec: start -----
ilikeheaps:plyboard:1: EVENT: 0305u(21590)
ilikeheaps:plyboard:1: Tapping: First tap(0->1).
ilikeheaps:plyboard:1: TAPPING_KEY=0305d(21482):1-
ilikeheaps:plyboard:1: ACTION: ACT_SWAP_HANDS[0:2C] layer_state:  default_layer_state: 
ilikeheaps:plyboard:1: keyboard_report: 00 | 2C 00 00 00 00 00 
ilikeheaps:plyboard:1: waiting_buffer_enq: { [7]=0602d(21553):0  [0]=0305u(21590):1- }
ilikeheaps:plyboard:1: ---- action_exec: process waiting_buffer -----
ilikeheaps:plyboard:1: Tapping: key event while last tap(>0).
ilikeheaps:plyboard:1: ACTION: ACT_LMODS[0:0F] layer_state:  default_layer_state: 
ilikeheaps:plyboard:1: keyboard_report: 00 | 2C 0F 00 00 00 00 
ilikeheaps:plyboard:1: processed: waiting_buffer[7] =0602d(21553):0 
ilikeheaps:plyboard:1: 
ilikeheaps:plyboard:1: Tapping: Tap release(1)
ilikeheaps:plyboard:1: ACTION: ACT_SWAP_HANDS[0:2C] layer_state:  default_layer_state: 
ilikeheaps:plyboard:1: keyboard_report: 00 | 00 0F 00 00 00 00 
ilikeheaps:plyboard:1: TAPPING_KEY=0000u(0):0 
ilikeheaps:plyboard:1: processed: waiting_buffer[0] =0000u(0):0 
ilikeheaps:plyboard:1: 
ilikeheaps:plyboard:1: 
ilikeheaps:plyboard:1: 
ilikeheaps:plyboard:1: ---- action_exec: start -----
ilikeheaps:plyboard:1: EVENT: 0102u(21626)
ilikeheaps:plyboard:1: ACTION: ACT_LMODS[0:0F] layer_state:  default_layer_state: 
ilikeheaps:plyboard:1: keyboard_report: 00 | 00 00 00 00 00 00 
ilikeheaps:plyboard:1: processed: 0602u(21626):0 
ilikeheaps:plyboard:1: 
ilikeheaps:plyboard:1: 
ilikeheaps:plyboard:1: ---- action_exec: start -----
ilikeheaps:plyboard:1: EVENT: 0305d(23288)
ilikeheaps:plyboard:1: Tapping: Start(Press tap key).
ilikeheaps:plyboard:1: TAPPING_KEY=0305d(23288):0 
ilikeheaps:plyboard:1: processed: 0305d(23288):0 
ilikeheaps:plyboard:1: 
ilikeheaps:plyboard:1: Tapping: End. Timeout. Not tap(0): 0000u(23488)
ilikeheaps:plyboard:1: ACTION: ACT_SWAP_HANDS[0:2C] layer_state:  default_layer_state: 
ilikeheaps:plyboard:1: TAPPING_KEY=0000u(0):0 
ilikeheaps:plyboard:1: 
ilikeheaps:plyboard:1: ---- action_exec: start -----
ilikeheaps:plyboard:1: EVENT: 0102d(23572)
ilikeheaps:plyboard:1: ACTION: ACT_LMODS[0:0F] layer_state:  default_layer_state: 
ilikeheaps:plyboard:1: keyboard_report: 00 | 0F 00 00 00 00 00 
ilikeheaps:plyboard:1: processed: 0602d(23572):0 
ilikeheaps:plyboard:1: 
ilikeheaps:plyboard:1: 
ilikeheaps:plyboard:1: ---- action_exec: start -----
ilikeheaps:plyboard:1: EVENT: 0102u(23798)
ilikeheaps:plyboard:1: ACTION: ACT_LMODS[0:0F] layer_state:  default_layer_state: 
ilikeheaps:plyboard:1: keyboard_report: 00 | 00 00 00 00 00 00 
ilikeheaps:plyboard:1: processed: 0602u(23798):0 
ilikeheaps:plyboard:1: 
ilikeheaps:plyboard:1: 
ilikeheaps:plyboard:1: ---- action_exec: start -----
ilikeheaps:plyboard:1: EVENT: 0305u(23843)
ilikeheaps:plyboard:1: ACTION: ACT_SWAP_HANDS[0:2C] layer_state:  default_layer_state: 
ilikeheaps:plyboard:1: processed: 0305u(23843):0 

[ilikeheaps]

Okay, found the (edit: an?) issue: I should read the manual and use PERMISSIVE_HOLD. Well, I did read it but didn't notice different tapping modes when reading about swap-hands and one shot modifiers. I assumed PERMISSIVE_HOLD behaviour when reading keys descriptions:

The Mod-Tap key MT(mod, kc) acts like a modifier when held, and a regular keycode when tapped. In other words, you can have a key that sends Escape when you tap it, but functions as a Control or Shift key when you hold it down.

SH_T(kc) -- Momentary swap when held, kc when tapped

Anyway:

1. SH_T still breaks the description - it works as both SH toggle and tap in the same press
2. I didn't find tests for swap-hands, would anyone like to see PR with mine after I fix their configuration?

[ilikeheaps]

I've set PERMISSIVE_HOLD for my keyboard but I am still having issues. Perhaps I will try to refine tests to isolate the problem.

[ilikeheaps]

Posted my tests (one failing, bug or wrong assumptions?) in #24420