addGeoJSON() fails to render valid geometries

[aoles]

Hi,

it seems that geoJSON geometry primitives such as "Point" or "Polygon" are not displayed by addGeoJSON(). I would expect them to be valid input as according to the specification and to geojsonlint::geojson_validate() they conform to the standard.

Cheers,
Andrzej

library(leaflet)
library(jsonlite)
library(geojsonlint)

polygon = list(
  type = "Polygon",
  coordinates = list(
    list(
      c(8.330469, 48.261570),
      c(8.339052, 48.261570),
      c(8.339052, 48.258227),
      c(8.330469, 48.258227),
      c(8.330469, 48.261570)
    )
  )
)

geojson_validate(toJSON(polygon, auto_unbox = TRUE))
#> [1] TRUE

leaflet() %>%
  addTiles() %>%
  addGeoJSON(polygon, color="#F00") %>%
  setView(lng = 8.330469, lat = 48.26157, zoom = 15)

feature <- list(
  type = "Feature",
  properties = "",
  geometry = polygon
)

leaflet() %>%
  addTiles() %>%
  addGeoJSON(feature, color="#F00") %>%
  setView(lng = 8.330469, lat = 48.26157, zoom = 15)

^{Created on 2019-05-03 by the reprex package (v0.2.1)}

[schloerke]

This line is causing the issue:

leaflet/javascript/src/methods.js

Line 594 in 44df7d1

let popup = feature.properties.popup;

[schloerke]

Check to make sure properties is not undefined. Or use extraInfo object properties

[jcheng5]

Thanks, @aoles! Just one nit with this example: properties = "" isn't valid GeoJSON, that should either be null or {}. (But I think the PR is fine despite this, since both "" and null are falsy)