Fixes to setup.py for pip install (holoviz#1782)

* Moved examples function to setup.py to avoid dependencies install

* Restored copy of examples function in util

* Added comment about duplication of the examples function

* Fixed message about holoviews command dependencies

holoviews/util/__init__.py

@@ -15,6 +15,7 @@
 Store.output_settings = OutputSettings
 
 
+
 def examples(path='holoviews-examples', verbose=False, force=False, root=__file__):
     """
     Copies the notebooks to the supplied path.
@@ -36,7 +37,6 @@ def examples(path='holoviews-examples', verbose=False, force=False, root=__file_
         print('Cannot find %s' % tree_root)
 
 
-
 class opts(param.ParameterizedFunction):
     """
     Utility function to set options either at the global level or on a

holoviews/util/command.py

@@ -15,7 +15,7 @@
 try:
     import nbformat, nbconvert
 except:
-    print('Both nbformat and nbconvert need to be installed to use the holoviews command')
+    print('nbformat, nbconvert and ipython need to be installed to use the holoviews command')
     sys.exit()
 try:
     from ..ipython.preprocessors import OptsMagicProcessor, OutputMagicProcessor

setup.py

@@ -1,7 +1,7 @@
 #!/usr/bin/env python
 
 import sys, os, glob
-from shutil import rmtree
+import shutil
 from collections import defaultdict
 try:
     from setuptools import setup
@@ -110,12 +110,35 @@ def walker(top, names):
             extensions[package].append(ext_str)
 
 
+# Note: This function should be identical to util.examples
+# (unfortunate and unavoidable duplication)
+def examples(path='holoviews-examples', verbose=False, force=False, root=__file__):
+    """
+    Copies the notebooks to the supplied path.
+    """
+    filepath = os.path.abspath(os.path.dirname(root))
+    example_dir = os.path.join(filepath, './examples')
+    if not os.path.exists(example_dir):
+        example_dir = os.path.join(filepath, '../examples')
+    if os.path.exists(path):
+        if not force:
+            print('%s directory already exists, either delete it or set the force flag' % path)
+            return
+        shutil.rmtree(path)
+    ignore = shutil.ignore_patterns('.ipynb_checkpoints','*.pyc','*~')
+    tree_root = os.path.abspath(example_dir)
+    if os.path.isdir(tree_root):
+        shutil.copytree(tree_root, path, ignore=ignore, symlinks=True)
+    else:
+        print('Cannot find %s' % tree_root)
+
+
+
 def package_assets(example_path):
     """
     Generates pseudo-packages for the examples directory.
     """
-    import holoviews
-    holoviews.util.examples(example_path, force=True, root=__file__)
+    examples(example_path, force=True, root=__file__)
     for root, dirs, files in os.walk(example_path):
         walker(root, dirs+files)
     setup_args['packages'] += packages
@@ -153,4 +176,4 @@ def package_assets(example_path):
     setup(**setup_args)
 
     if os.path.isdir(example_path):
-        rmtree(example_path)
+        shutil.rmtree(example_path)