What would you have done in this situation?

I was at this open sale in a line buying little wine glasses. I had them all in a bag I bought. In front of me getting her stuff checked out at the register was this huge black woman. The girl at the register (who I am friends with) asked me how many I bought, to which I bluntly told her that she'll see in a sec. The girl told the black woman that I'm her friend and that I'm just messing with her (I don't know why but she's weird so whatever) and the black woman says "well he's about to catch a whuppin" before trying to walk THROUGH me.

I didn't think anything of it at the time but now I'm kinda pissed off that I didn't say anything to her. Should I have?
What would you have done in this situation?
Add Opinion