TST: add message to nose.SkipTest

Author: cpcloud

pandas/io/tests/test_html.py

@@ -37,7 +37,7 @@ def _have_module(module_name):
 
 def _skip_if_no(module_name):
     if not _have_module(module_name):
-        raise nose.SkipTest
+        raise nose.SkipTest("{0} not found".format(module_name))
 
 
 def _skip_if_none_of(module_names):
@@ -46,14 +46,16 @@ def _skip_if_none_of(module_names):
         if module_names == 'bs4':
             import bs4
             if bs4.__version__ == LooseVersion('4.2.0'):
-                raise nose.SkipTest
+                raise nose.SkipTest("Bad version of bs4: 4.2.0")
     else:
-        if not all(_have_module(module_name) for module_name in module_names):
-            raise nose.SkipTest
+        not_found = [module_name for module_name in module_names if not
+                     _have_module(module_name)]
+        if not_found == module_names:
+            raise nose.SkipTest("{0} not found".format(not_found))
         if 'bs4' in module_names:
             import bs4
             if bs4.__version__ == LooseVersion('4.2.0'):
-                raise nose.SkipTest
+                raise nose.SkipTest("Bad version of bs4: 4.2.0")
 
 
 DATA_PATH = get_data_path()