What is the test for direct aider and abettor of premeditated murder?

^8. A direct aider and abettor of premeditated murder "acts with the mens rea required for first degree murder" when "the defendant aided or encouraged the commission of the murder with knowledge of the unlawful purpose of the perpetrator and with the intent or purpose of committing, encouraging, or facilitating its commission. [Citation.] Because the mental state componentconsisting of intent and knowledgeextends to the entire crime, it preserves the distinction between assisting the predicate crime of second degree murder and assisting the greater offense of first degree premeditated murder. ([People v.] McCoy [(2001)] 25 Cal.4th [1111,] 1118, ['an aider and abettor's mental state must be at least that required of the direct perpetrator']; cf. Rosemond v. United States (2014) 572 U.S. [65], [76-77].) An aider and abettor who knowingly and intentionally assists a confederate to kill someone could be found to have acted willfully, deliberately, and with premeditation, having formed his own culpable intent." (People v. Chiu (2014) 59 Cal.4th 155, 167.)

Under the natural and probable consequences doctrine, a "'person who knowingly aids and abets criminal conduct is guilty of not only the intended crime . . . but also of any other crime the perpetrator actually commits . . . that is a natural and probable consequence of the intended crime.'" (People v. Medina (2009) 46 Cal.4th 913, 920.)