test_that('plot_prof outputs a plot object',{

  obs <- data.frame(Date = '2020-01-01',
                   Depth = 0:5,
                   TEMP = 29:24)

  sim <- matrix(c(28,28,28,27,25,24),
               nrow = 6,
               ncol = 1)

  expect_true(is.object(plot_prof(sim = sim,
            obs = obs,
            sim.start = '2020-01-01',
            sim.end = '2020-01-01',
            plot.start = '2020-01-01',
            plot.end = '2020-01-01',
            xlabel = 'degrees',
            min.depth = 0,
            max.depth = 5,
            by.value = 1)))

})


test_that('plot_prof accept right format of date',{

  obs <- data.frame(Date = '2020-01-01',
                   Depth = 0:5,
                   TEMP = 29:24)

  sim <- matrix(c(28,28,28,27,25,24),
               nrow = 6,
               ncol = 1)

  expect_error(is.object(plot_prof(sim = sim,
                                  obs = obs,
                                  sim.start = '01-01-2020',
                                  sim.end = '2020-01-01',
                                  plot.start = '2020-01-01',
                                  plot.end = '2020-01-01',
                                  xlabel = 'degrees',
                                  min.depth = 0,
                                  max.depth = 5,
                                  by.value = 1)))

})