expect_maps_equal <- function(m1, m2) {
  attr(m1$x, "leafletData") <- NULL
  attr(m2$x, "leafletData") <- NULL
  expect_equal(m1, m2, ignore_function_env = TRUE, ignore_formula_env = TRUE)
}

normalize_multipolygon <- function(df) {
  # A multipolygon is a nested list of lng/lat data frames. Each data frame
  # represents a single polygon (may be an island or a hole), that is, a series
  # of points where the last point is the same as the first point.
  #
  # This function walks the nested list, and for each lng/lat data frame, it
  # reorders the points so that equivalent polygons always have the same points
  # in the same order. The data frame rows are rotated so that the first row
  # contains the smallest lng; ties are broken with lat.

  if (is.list(df) && !is.data.frame(df)) {
    return(lapply(df, normalize_multipolygon))
  }

  stopifnot(identical(names(df), c("lng", "lat")))
  if (nrow(df) <= 1) {
    return(df)
  }
  if (!all(df[1,] == df[nrow(df),])) {
    stop("Malformed polygon; first and last rows were not identical")
  }
  # Remove duplicate point, for now
  df <- df[-nrow(df),]
  tip <- order(df[,1], df[,2])[[1]]
  idx <- seq_len(nrow(df)) >= tip
  df <- rbind(df[idx,], df[!idx,], df[tip,])
  row.names(df) <- NULL
  df
}

test_that("normalize", {
  skip_if_not_installed("sf")

  library(sf)
  library(sp)

  ### polygons --------------------------------------------------------------

  pgontest <- function(x) {
    leaflet(x) %>% addTiles() %>% addPolygons()
  }

  poldata <- st_as_sf(gadmCHE)

  (r1 <- pgontest(poldata))
  (r2 <- pgontest(st_geometry(poldata)))
  (r3 <- pgontest(st_geometry(poldata)[[1]]))
  (r4 <- pgontest(st_geometry(poldata)[[1]][[1]] %>% st_polygon()))
  (r5 <- pgontest(gadmCHE))
  (r6 <- pgontest(polygons(gadmCHE)))
  (r7 <- pgontest(polygons(gadmCHE)@polygons[[1]]))
  (r8 <- pgontest(polygons(gadmCHE)@polygons[[1]]@Polygons[[1]]))

  expect_maps_equal(r1, r2)
  expect_maps_equal(r3, r4)
  expect_maps_equal(r1, r5)

  ### lines -----------------------------------------------------------------

  lindata <- st_as_sf(atlStorms2005)

  plinetest <- function(x) {
    leaflet(x) %>% addTiles() %>% addPolylines()
  }

  (l1 <- plinetest(lindata))  # sf, data.frame
  (l2 <- plinetest(st_geometry(lindata)))  # sfc_LINESTRING, sfc
  (l3 <- plinetest(st_geometry(lindata)[[1]]))  # XY, LINESTRING, sfg
  (l4 <- plinetest(st_multilinestring(st_geometry(lindata))))  # XY, MULTILINESTRING, sfg
  (l5 <- plinetest(atlStorms2005))
  (l6 <- plinetest(SpatialLines(atlStorms2005@lines)))
  (l7 <- plinetest(atlStorms2005@lines[[1]]))
  (l8 <- plinetest(atlStorms2005@lines[[1]]@Lines[[1]]))

  expect_maps_equal(l1, l2)
  expect_maps_equal(l1, l5)
  expect_maps_equal(l1, l6)
  expect_maps_equal(l3, l7)
  expect_maps_equal(l3, l8)

  ### points ----------------------------------------------------------------
  ptsdata <- st_as_sf(breweries91)
  class(ptsdata)  # sf, data.frame
  class(st_geometry(ptsdata))  # sfc_POINT, sfc
  class(st_geometry(ptsdata)[[1]])  # XY, POINT, sfg
  class(do.call(rbind, unclass(st_geometry(ptsdata))) %>% st_multipoint())  # XY, POINT, sfg

  (p1 <- leaflet() %>% addTiles() %>% addCircleMarkers(data = ptsdata))
  (p2 <- leaflet() %>% addTiles() %>% addCircleMarkers(data = st_geometry(ptsdata)))
  (p3 <- leaflet() %>% addTiles() %>% addCircleMarkers(data = st_geometry(ptsdata)[[1]]))
  # leaflet() %>% addTiles() %>% addCircleMarkers(data = do.call(rbind, unclass(st_geometry(ptsdata))) %>% st_multipoint())

  expect_maps_equal(p1, p2)

  (p4 <- leaflet() %>% addTiles() %>% addCircleMarkers(data = ptsdata[FALSE, ]))
  (p5 <- leaflet() %>% addTiles() %>% addCircleMarkers(data = st_geometry(ptsdata)[FALSE]))
  (p6 <- leaflet() %>% addTiles() %>% addCircleMarkers(lng = numeric(0), lat = numeric(0)))
  expect_maps_equal(p4, p5)
  expect_maps_equal(p4, p6)

  ### lines -----------------------------------------------------------------
  polys <-
    Polygons(list(
      create_square(),
      create_square(, 5, 5),
      create_square(1, hole = TRUE),
      create_square(0.4, 4.25, 4.25, hole = TRUE),
      create_square(1, 5, 5, hole = TRUE)
    ), "A")
  comment(polys) <- "0 0 1 2 2"

  spolys <- SpatialPolygons(list(
    polys
  ))
  stspolys <- st_as_sf(spolys)

  testthat::expect_snapshot_output(derivePolygons(spolys))

  if (packageVersion("sf") >= "1.0-10") {
    # Test https://github.com/rstudio/leaflet/issues/833
    # Ensure that if a Polygons object is missing hole assignment info, we can
    # infer it using sf v1.0-10 or above.
    mp1 <- to_multipolygon(polys)
    mp2 <- to_multipolygon(`comment<-`(polys, NULL))
    expect_identical(
      normalize_multipolygon(mp1),
      normalize_multipolygon(mp2)
    )
  }

  (l101 <- leaflet(spolys) %>% addPolygons())
  (l102 <- leaflet(stspolys) %>% addPolygons())
  expect_maps_equal(l101, l102)
  (l103 <- leaflet(spolys) %>% addPolylines())
  (l104 <- leaflet(stspolys) %>% addPolylines())
  expect_maps_equal(l103, l104)

  slines <- SpatialLines(list(
    Lines(list(
      create_square(type = Line),
      create_square(, 5, 5, type = Line),
      create_square(1, hole = TRUE, type = Line),
      create_square(1, 5, 5, hole = TRUE, type = Line),
      create_square(0.4, 4.25, 4.25, hole = TRUE, type = Line)
    ), "A")
  ))
  stslines <- st_as_sf(slines)
  (l105 <- leaflet(slines) %>% addPolylines())
  (l106 <- leaflet(stslines) %>% addPolylines())
  expect_maps_equal(l105, l106)
})