Some matcher libraries or legacy codebases require a *testing.T GinkgoT implements an interface analogous to *testing.T and can be used if the library in question accepts *testing.T through an interface

For example, with testify: assert.Equal(GinkgoT(), 123, 123, "they should be equal")

Or with gomock: gomock.NewController(GinkgoT())

GinkgoT() takes an optional offset argument that can be used to get the correct line number associated with the failure.