Did the Messenger of Allah, peace and blessings be upon him, appoint a successor for himself from among the Companions?

Scholars have differed on whether the succession of Abu Bakr, may Allah be pleased with him, was by divine decree (nass) or by consultation (shura), but they have agreed on its validity due to the consensus of the Companions. Authentic hadiths indicate that the Prophet, peace and blessings be upon him, intended to designate Abu Bakr for the caliphate, as in his saying to Aisha: "Call your father and your brother for me so that I may write a document, for I fear that someone may wish for it and another may say, 'I am more deserving.' But Allah and the believers would refuse none but Abu Bakr." As for the claim of a divine designation for the caliphate of Ali, may Allah be pleased with him, it is refuted by what is authentically reported from Ali himself, that he had no such covenant from the Prophet. Had there been one, he would have fought Abu Bakr and Umar. He clarified that the Companions chose Abu Bakr for the caliphate because he led the prayers during the Prophet's illness, then Umar, then Uthman, and all of this was through consultation.