What is the test for multiple punishment under section 654 of the California Penal Code for a single assault?

Section 654, subdivision (a) states that an "act or omission that is punishable in different ways by different provisions of law shall be punished under the provision that provides for the longest potential term of imprisonment, but in no case shall the act or omission be punished under more than one provision." The statute aims " 'to insure that a defendant's punishment will be commensurate with his culpability.' " (People v. Latimer (1993) 5 Cal.4th 1203, 1211.) As a general rule, "[s]ection 654 prohibits multiple punishment for a single physical act that violates different provisions of law." (People v. Jones (2012) 54 Cal.4th 350, 358.)