This commits add the SH_OS keycode, which works similarly to one shot
layers:
* while pressed, the keyboard is swapped
* if no keys were pressed while it was pressed, the next key press is
swapped
SH_OS also supports chaining with one shot layers:
OSL(x) + SH_OS + key interprets the key press on the oneshot layer.
The ONESHOT_TIMEOUT setting used by one shot keys and layers is also
used by oneshot swap hands. In the above chaining scenario the timeout
of the oneshot layer is reset when swap hands is activated.
Resolves#2682
* Added callbacks to one shot modifier changes
* Altered signature of callback functions
* Reordered the callback methods, shortened brief documentation
* Added One Shot Modifier callback documentation
* First attempt at unit tests
* Revert "First attempt at unit tests"
This reverts commit 5ec21a7822.
* Simplified oneshot function implementations
* Made clear_oneshot_locked_mods to be conform action_util.h, adhering to the (void) signature
* Made used datatypes for oneshot mods consistently unsigned integers
* Corrected callback to call clear callback when clear_oneshot_locked_mods is invoked
* Simplified oneshot equals statements
* Corrected return type and signature of get and set oneshot locked mods
* Consolidated one shot callbacks, added initial layer callback version
* Fixed non-updating one shot layer variable after timeout or other clear, added code comments
* Added better one shot key docs
This commit is mostly a cherry-pick from `ahtn` at
https://github.com/tmk/tmk_keyboard/pull/255.
These are the changes:
* Adds ACTION_LAYER_ONESHOT
* Adds ONESHOT_TAP_TOGGLE
* Mentions sticky keys in the docs on oneshot.
- new macro_mods bit field for mods applied by macros
- weak_mods now only used for ACT_{L,R}MODS (i.e. LSFT, RSFT, LCTL etc.)
- clear the _weak_ mods on every key *pressed* such that LSFT etc.
can no more interfere with the next key
