What is the test for corroborating the testimony of an accomplice in a criminal case?

below to determine whether it discloses substantial evidence that is, evidence that is reasonable, credible, and of solid value from which a reasonable trier of fact could find the defendant guilty beyond a reasonable doubt.' [Citation.] We view the evidence in the light most favorable to respondent and presume in support of the judgment the existence of every fact the trier of fact reasonably could deduce from the evidence. [Citation.] The jury, not the appellate court, must be convinced of guilt beyond a reasonable doubt; for us, '[t]he test is whether substantial evidence supports the decision, not whether the evidence proves guilt beyond a reasonable doubt.'" (People v. Vu (2006) 143 Cal.App.4th 1009, 1024 (Vu).)

An accomplice is "one who is liable to prosecution for the identical offense charged against the defendant on trial in the cause in which the testimony of the accomplice is given." ( 1111.) The testimony of accomplices must be corroborated by "such other evidence as shall tend to connect the defendant with the commission of the offense." (Ibid.) Such evidence may not come from, or require "'aid or assistance'" from, the testimony of other accomplices or the accomplice himself. (People v. Davis (2005) 36 Cal.4th 510, 543.)