package example import ( "testing" gomock "github.com/golang/mock/gomock" ) func TestFoo(t *testing.T) { ctrl := gomock.NewController(t) // Assert that Bar() is invoked. defer ctrl.Finish() m := NewMockFoo(ctrl) // Asserts that the first and only call to Bar() is passed 99. // Anything else will fail. m. EXPECT(). Bar(gomock.Eq(99)). Return(101) SUT(m) }