Remove geopandas as an installation requirement

closes #178

.travis.yml

@@ -57,6 +57,7 @@ install:
       export MPLLOCALFREETYPE=1
       pip install matplotlib --no-binary matplotlib
       pip install scikit-misc
+      pip install geopandas
       pip install -e .
     fi
   - |

doc/changelog.rst

@@ -9,6 +9,9 @@ API Changes
 ***********
 
 - Plotnine 0.5.0 only supports Python 3.5 and higher
+- geopandas has been removed as a requirement for installation. Users of
+  :class:`~plotnine.geoms.geom_map` will have to install it separately.
+  (:issue:`178`)
 
 Bug Fixes
 *********

plotnine/geoms/geom_map.py

@@ -3,7 +3,15 @@
 from matplotlib.collections import PatchCollection, LineCollection
 from descartes.patch import PolygonPatch
 
+try:
+    import geopandas  # noqa: F401
+except ImportError:
+    HAS_GEOPANDAS = False
+else:
+    HAS_GEOPANDAS = True
+
 from ..doctools import document
+from ..exceptions import PlotnineError
 from ..utils import to_rgba, SIZE_FACTOR
 from .geom import geom
 from .geom_point import geom_point
@@ -40,14 +48,10 @@ class geom_map(geom):
     legend_geom = 'polygon'
 
     def __init__(self, *args, **kwargs):
-        import sys
-        if sys.version_info >= (3, 7, 0):
-            from ..exceptions import PlotnineError
+        if not HAS_GEOPANDAS:
             raise PlotnineError(
-                "geom_map does not work on Python 3.7 "
-                "for more information see "
-                "https://github.com/has2k1/plotnine/issues/178 "
-                "https://github.com/jswhit/pyproj/issues/136 "
+                "geom_map requires geopandas. "
+                "Please install geopandas."
             )
         geom.__init__(self, *args, **kwargs)
         # Almost all geodataframes loaded from shapefiles

setup.py

@@ -56,15 +56,6 @@ def get_required_packages():
                         # 'geopandas >= 0.3.0',
                         'descartes >= 1.1.0'
                         ]
-    # FIXME: Remove and uncomment above when pyproj supports
-    # Python 3.7
-    # https://github.com/has2k1/plotnine/issues/178
-    # https://github.com/jswhit/pyproj/issues/136
-    import sys
-    if sys.version_info < (3, 7, 0):
-        install_requires.extend([
-            'geopandas >= 0.3.0',
-        ])
     return install_requires