Does the +1 from Improved Pact Weapon carry through when used as a spell focus?

@JeremyECrawford Does the +1 from Improved Pact Weapon carry through when used as a spell focus?

— McGill (@RandomMagilla) December 19, 2017

The bonus to attack rolls conferred by Improve Pact Weapon applies to the weapon's attack rolls, not to a spell's attack rolls. #DnD https://t.co/t8HIFPxnwj

— Jeremy Crawford (@JeremyECrawford) December 19, 2017