Nothing
      library(htmltools)
library(leaflet)
test_that("labelgun", {
  df <- breweries91
  df$weight <- seq_len(nrow(df))
  m <- leaflet() %>%
    addMarkers(
      data = df, label = ~ paste0(weight, " - ", brewery),
      group = "hidemarkers_1",
      labelOptions = labelOptions(permanent = TRUE)
    ) %>%
    addLabelgun("hidemarkers_1")
  expect_is(m, "leaflet")
  deps <- findDependencies(m)
  expect_equal(deps[[length(deps)]]$name, "lfx-labelgun")
  expect_true(m$x$calls[[2]]$method == "addLabelgun")
  expect_true(m$x$calls[[2]]$args[[1]] == "hidemarkers_1")
  expect_error(leaflet() %>% addLabelgun())
})
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