What is the test for a motion under section 2255(b) of the Criminal Code seeking relief under Section 2255?

McAllister further argues that the district court abused its discretion by denying his section 2255 motion without holding an evidentiary hearing. A district court must hold a hearing on such a motion unless the motion and case records "conclusively show that the prisoner is entitled to no relief." 28 U.S.C. 2255(b). Even so, a district court may in its discretion decline to conduct a full evidentiary hearing and choose instead "to expand the record," if necessary, with an affidavit, for example, before determining if a hearing is required under section 2255(b). Chang v. United States, 250 F.3d 79, 85-86 (2d Cir. 2001).