# ------------------------------------------------------------------------------
# slide2_*()

test_that("slide2_*() works", {
  expect_identical(slide2_vec(1L, 1L, ~.x + .y), 2L)
  expect_identical(slide2_int(1L, 1L, ~.x + .y), 2L)
})

test_that("slide2_*() retains names of x", {
  expect_identical(slide2_vec(c(x = 1L), c(y = 1L), ~.x + .y), c(x = 2L))
  expect_identical(slide2_int(c(x = 1L), c(y = 1L), ~.x + .y), c(x = 2L))
})

test_that("slide2_vec() can simplify automatically", {
  expect_identical(slide2_vec(1, 2, ~.x + .y, .ptype = NULL), 3)
})

test_that("slide2_vec() errors if it can't simplify", {
  fn <- function(x, y) if (x == 1L) {1} else {"hi"}
  expect_snapshot({
    (expect_error(
      slide2_vec(1:2, 1:2, fn, .ptype = NULL),
      class = "vctrs_error_incompatible_type"
    ))
  })
})

test_that("slide2_*() errors if it can't cast", {
  fn <- function(x, y) if (x == 1L) {1} else {"hi"}
  expect_snapshot({
    (expect_error(
      slide2_int(1:2, 1:2, fn),
      class = "vctrs_error_incompatible_type"
    ))
  })
})

# ------------------------------------------------------------------------------
# suffix tests

test_that("slide2_int() works", {
  expect_identical(slide2_int(1L, 1L, ~.x + .y), 2L)
})

test_that("slide2_int() can coerce", {
  expect_identical(slide2_int(1, 1, ~.x + .y), 2L)
})

test_that("slide2_dbl() works", {
  expect_identical(slide2_dbl(1, 1, ~.x), 1)
})

test_that("slide2_dbl() can coerce", {
  expect_identical(slide2_dbl(1L, 1L, ~.x + .y), 2)
})

test_that("slide2_chr() works", {
  expect_identical(slide2_chr("x", 1, ~.x), "x")
})

test_that("slide2_chr() cannot coerce", {
  expect_snapshot({
    (expect_error(slide2_chr(1, 1, ~.x + .y), class = "vctrs_error_incompatible_type"))
  })
})

test_that("slide2_lgl() works", {
  expect_identical(slide2_lgl(TRUE, 1, ~.x), TRUE)
})

test_that("slide2_lgl() can coerce", {
  expect_identical(slide2_lgl(1, 0, ~.x + .y), TRUE)
})

# ------------------------------------------------------------------------------
# data frame suffix tests

test_that("slide2_dfr() works", {
  expect_identical(
    slide2_dfr(
      1:2,
      1:2,
      ~new_data_frame(list(x = list(.x), y = list(.y))),
      .before = 1
    ),
    data_frame(
      x = list(1L, 1:2),
      y = list(1L, 1:2)
    )
  )
})

test_that("slide2_dfc() works", {
  x <- 1:2

  fn <- function(x, y) {
    if (length(x) == 1) {
      data.frame(x1 = x, y1 = y)
    } else {
      data.frame(x2 = x, y2 = y)
    }
  }

  expect_identical(
    slide2_dfc(x, x, fn, .before = 1),
    data.frame(
      x1 = c(1L, 1L),
      y1 = c(1L, 1L),
      x2 = 1:2,
      y2 = 1:2
    )
  )
})

# ------------------------------------------------------------------------------
# .ptype

test_that("`.ptype = NULL` is size stable (#78)", {
  expect_length(slide2_vec(1:4, 1:4, ~.x, .step = 2), 4)
  expect_length(slide2_vec(1:4, 1:4, ~1, .before = 1, .complete = TRUE), 4)
})

test_that("`slide2_vec()` falls back to `c()` method as required", {
  local_c_foobar()

  expect_identical(slide2_vec(1:3, 1:3, ~foobar(.x), .ptype = foobar(integer())), foobar(1:3))
  expect_condition(slide2_vec(1:3, 1:3, ~foobar(.x), .ptype = foobar(integer())), class = "slider_c_foobar")

  expect_identical(slide2_vec(1:3, 1:3, ~foobar(.x)), foobar(1:3))
  expect_condition(slide2_vec(1:3, 1:3, ~foobar(.x)), class = "slider_c_foobar")
})

# ------------------------------------------------------------------------------
# .step

test_that(".step produces typed `NA` values", {
  expect_identical(slide2_int(1:3, 1:3, ~.x, .step = 2), c(1L, NA, 3L))
  expect_identical(slide2_dbl(1:3, 1:3, ~.x, .step = 2), c(1, NA, 3))
  expect_identical(slide2_chr(c("a", "b", "c"), 1:3, ~.x, .step = 2), c("a", NA, "c"))
  expect_identical(slide2_vec(1:3, 1:3, ~.x, .step = 2), c(1L, NA, 3L))
  expect_identical(slide2_vec(1:3, 1:3, ~.x, .step = 2, .ptype = integer()), c(1L, NA, 3L))
})

# ------------------------------------------------------------------------------
# .complete

test_that(".complete produces typed `NA` values", {
  expect_identical(slide2_int(1:3, 1:3, ~1L, .before = 1, .complete = TRUE), c(NA, 1L, 1L))
  expect_identical(slide2_dbl(1:3, 1:3, ~1, .before = 1, .complete = TRUE), c(NA, 1, 1))
  expect_identical(slide2_chr(1:3, 1:3, ~"1", .before = 1, .complete = TRUE), c(NA, "1", "1"))
  expect_identical(slide2_vec(1:3, 1:3, ~1, .before = 1, .complete = TRUE), c(NA, 1, 1))
  expect_identical(slide2_vec(1:3, 1:3, ~1, .before = 1, .complete = TRUE, .ptype = integer()), c(NA, 1L, 1L))
})