rm(list=ls())
## =============================================================================
slicer_pars <- list(
  A = seq(from = 100, 700,100),
  B = seq(from = 10, 80, 10),
  C = seq(1, 9, 1))
SlicerFun <- function(A, B, C){
  A + B + C
}
slicer_power_array <- PowerGrid(pars = slicer_pars, fun = SlicerFun,
                                summarize = FALSE)

result1 <- ArraySlicer(slicer_power_array, slicer = NULL)
test_that(
  "Empty list as slicer, leaves array contents unchanged",
  {expect_equal(result1, slicer_power_array, ignore_attr = TRUE)}
)

result2 <- ArraySlicer(slicer_power_array, slicer=list(A = 100, B = 10, C = 1))
test_that(
  "Fully specified values gives single value",
  {expect_equal(result2, 111, ignore_attr = TRUE)}
)

## =============================================================================
test_that(
  "Appropriate error thrown when a bad dimension name used",
  {expect_error(ArraySlicer(slicer_power_array,
                        slicer = list(badname = 0.9, B = 20)))}
)

test_that(
  "Appropriate error thrown when a bad value used",
  {expect_error(ArraySlicer(slicer_power_array,
                        slicer = list(A = NA, C = 3)))}
)

## =============================================================================
result3 <- ArraySlicer(slicer_power_array, slicer=list(A=c(400,100), B=40)) |>
  as.array() |>
  unclass()
comparison3 <-
  .mapply(SlicerFun, expand.grid(A = c(400, 100), B = 40, C=seq(1, 9, 1)),
          MoreArgs = NULL) |>
  sapply(I, simplify = "array") |>
  array(dim = c(2, 9))
test_that(
  "Output has elements in order specified by slicer",
  {expect_equal(result3, comparison3, ignore_attr = TRUE)}
)