What is the fallacy when trying to evaluate the FT of the dirac delta function via integration by parts?

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When evaluating the Fourier transform of the dirac delta function, if I call the dirac delta function dv as a basis to try to integrate by parts, then because the integral of the dirac delta function is 1 = v then all that is left is u - the integral of du which would reduce to 0. But the actual FT is 1. The same question would apply to ANY function with an integral of 1 across the real line (i.e. finite signal with total AOC of 1); there's no way the FTs are just 0. Where is the mistake in this reasoning? Is there an approach to evaluate the FT for any given function with an integral of 1?