test_that("ts_span does the same as base window", {
  ts_win2 <- ts_(window)
  expect_equal(
    ts_win2(ts_c(mdeaths, fdeaths), start = c(1978, 3)),
    ts_span(ts_c(mdeaths, fdeaths), start = "1978-03-01")
  )

  expect_equal(
    ts_win2(ts_c(austres), start = c(1978, 2)),
    ts_span(ts_c(austres), start = "1978-04-01")
  )

  expect_equal(
    ts_win2(ts_c(mdeaths, fdeaths), end = c(1978, 3)),
    ts_span(ts_c(mdeaths, fdeaths), end = "1978-03-01")
  )

  expect_equal(
    ts_win2(ts_c(austres), end = c(1978, 2)),
    ts_span(ts_c(austres), end = "1978-04-01")
  )

  expect_error(
    ts_span(ts_c(austres), start = "1978-06-01", end = "1978-04-01")
  )

  x <- ts_df(austres)

  expect_equal(x[1, 1], ts_summary(austres)$start)
  expect_equal(x[nrow(x), 1], ts_summary(austres)$end)
})

test_that("'by' strings are accepted (#106)", {
  expect_equal(
    ts_span(mdeaths, start = "197903"),
    ts_span(mdeaths, start = "-10 month")
  )
  expect_equal(
    ts_span(mdeaths, end = "197402"),
    ts_span(mdeaths, end = 2)
  )
})

test_that("works with non-heuristic frequencies (#106)", {
  expect_equal(
    ts_span(EuStockMarkets, start = "-1 year"),
    ts_span(EuStockMarkets, start = "19970827")
  )

  expect_equal(
    time(ts_span(EuStockMarkets, end = 5))[1:5],
    time(EuStockMarkets)[1:5]
  )

  expect_equal(
    time(ts_span(EuStockMarkets, end = 1))[1],
    time(EuStockMarkets)[1]
  )
})



test_that("extending by NA works", {
  expect_equal(
    ts_span(mdeaths, end = "19801201", extend = TRUE),
    window(mdeaths, end = c(1980, 12), extend = TRUE)
  )

  expect_equal(
    ts_span(mdeaths, start = "1973", extend = TRUE),
    window(mdeaths, start = 1973, extend = TRUE)
  )
})

test_that("extending by NA works for different frequencies", {
  x <- ts_span(ts_df(ts_c(AirPassengers, austres)), start = 1930, extend = TRUE)
  expect_identical(
    ts_span(x, start = "1930-01-01", end = "1930-01-01")$value,
    c(NA_real_, NA_real_)
  )
})


test_that("extending by template works", {
  target <-
    ts_span(ts_span(discoveries, template = AirPassengers, extend = FALSE), template = AirPassengers, extend = TRUE)
  actual <- ts_span(ts_span(discoveries, template = AirPassengers, extend = TRUE))
  expect_equal(target, actual)
})