What is the test for admitting evidence of past conduct in a criminal case?

The trial court's ruling was correct. Evidence Code section 1101, subdivision (b) allows the admission of evidence of past conduct to show, among other things, intent. It has long been held that a prior sale of narcotics is admissible to show a defendant's intent to sell on another occasion. (See People v. Pijal (1973) 33 Cal.App.3d 682, 691.)