- For protocols like Balancer and Curve, which expect funds to be in the router at the time of swap, we must support also transferring funds from the user into the router. Doing this in the router would mean we are dealing with transfers in two different places: in the router main methods and in the executors. To avoid this, we are now performing transfers just in the executors, and two transfer types have been added to support transfers into the router.
TODO:
- Add this for Balancer and Curve (only added for USV4 atm).
- TODO consider renaming TRANSFER_FROM and TRANSFER_PERMIT2 to include "pool" in the name
- Add more test cases for sequential swap and single swap to match those of split swap (fee, slippage), to catch errors more easily if someone makes a small code change to either the single or sequential methods
- Excluded USV3 and USV4 tests on sequential and single swap, since these tests were more to test USV3 and USV4 executor functionality than the high level sswap methods - they should already be sufficiently tested.
- Remove `testSplitSwapSimple` and `testSplitSwapSingleUSV3` since this is already tested by several other high-level methods (see single USV3 and single USV4 tests). We should prioritize integration-testing public methods over private methods.
