GeoJsonTooltip warn for GeometryCollection (#988)

jtbaker · Conengmo · commit f4d024d97c20 · 2018-12-09T11:01:37.000+01:00
Warn when a user renders a GeoJsonTooltip that uses a geojson with a GeometryCollection in it.

Add a test that verifies the warning triggers correctly.
diff --git a/folium/features.py b/folium/features.py
@@ -713,10 +713,24 @@ def __init__(self, fields, aliases=None, labels=True,
             # noqa outside of type checking.
             self.style = style
 
+    def warn_for_geometry_collections(self):
+        """Checks for GeoJson GeometryCollection features to warn user about incompatibility."""
+        geom_collections = [
+            feature.get('properties') if feature.get('properties') is not None else key
+            for key, feature in enumerate(self._parent.data['features'])
+            if feature['geometry']['type'] == 'GeometryCollection'
+        ]
+        if any(geom_collections):
+            warnings.warn(
+                "GeoJsonTooltip is not configured to render tooltips for GeoJson GeometryCollection geometries. "
+                "Please consider reworking these features: {} to MultiPolygon for full functionality.\n"
+                "https://tools.ietf.org/html/rfc7946#page-9".format(geom_collections), UserWarning)
+
     def render(self, **kwargs):
         """Renders the HTML representation of the element."""
         if isinstance(self._parent, GeoJson):
             keys = tuple(self._parent.data['features'][0]['properties'].keys())
+            self.warn_for_geometry_collections()
         elif isinstance(self._parent, TopoJson):
             obj_name = self._parent.object_path.split('.')[-1]
             keys = tuple(self._parent.data['objects'][obj_name][
diff --git a/tests/kuntarajat.geojson b/tests/kuntarajat.geojson
diff --git a/tests/test_features.py b/tests/test_features.py
@@ -6,16 +6,16 @@
 
 """
 
-from __future__ import (absolute_import, division, print_function)
-
 import os
-
-from six import text_type
+import warnings
 
 from branca.element import Element
 
-from folium import Map, Popup
 import folium
+from folium import Map, Popup
+
+from six import text_type
+
 
 tmpl = """
 <!DOCTYPE html>
@@ -29,6 +29,10 @@
 """  # noqa
 
 
+# Root path variable
+rootpath = os.path.abspath(os.path.dirname(__file__))
+
+
 # Figure
 def test_figure_creation():
     f = folium.Figure()
@@ -105,3 +109,15 @@ def test_color_line():
         opacity=1)
     m.add_child(color_line)
     m._repr_html_()
+
+
+# GeoJsonTooltip GeometryCollection
+def test_geojson_tooltip():
+    m = folium.Map([30.5, -97.5], zoom_start=10)
+    folium.GeoJson(os.path.join(rootpath, "kuntarajat.geojson"),
+                   tooltip=folium.GeoJsonTooltip(fields=['code', 'name'])
+                   ).add_to(m)
+    with warnings.catch_warnings(record=True) as w:
+        warnings.simplefilter('always')
+        m._repr_html_()
+        assert issubclass(w[-1].category, UserWarning), "GeoJsonTooltip GeometryCollection test failed."
