Detect whether we are running in a Conda environment and adjust get_include() (#1877)

pybind11/__init__.py

@@ -10,9 +10,17 @@ def get_include(user=False):
     virtualenv = hasattr(sys, 'real_prefix') or \
         sys.prefix != getattr(sys, "base_prefix", sys.prefix)
 
+    # Are we running in a conda environment?
+    conda = os.path.exists(os.path.join(sys.prefix, 'conda-meta'))
+
     if virtualenv:
         return os.path.join(sys.prefix, 'include', 'site',
                             'python' + sys.version[:3])
+    elif conda:
+        if os.name == 'nt':
+            return os.path.join(sys.prefix, 'Library', 'include')
+        else:
+            return os.path.join(sys.prefix, 'include')
     else:
         dist = Distribution({'name': 'pybind11'})
         dist.parse_config_files()