What is the test for calculating profit under s. 9(1) of the Income Tax Act?

34 That is not to minimize the key role played by such well-accepted business principles (as I shall hereafter refer to them) in the profit-computation process. In Friesen v. Canada, 1995 CanLII 62 (SCC), [1995] 3 S.C.R. 103, Major J. made the following observation at para. 41: The Act does not define “profit” nor does it provide any specific rules for the computation of profit. Tax jurisprudence has established that the determination of profit under s. 9(1) is a question of law to be determined according to the business test of “well-accepted principles of business (or accounting) practice” or “well-accepted principles of commercial trading” except where these are inconsistent with the specific provisions of the Income Tax Act. . . .