Make show option compatible with Python 2.6.

Change-Id: I573ba628e1f7d4e1f6d71223e27f2301db7eb080
Closes-Bug: #1322931

cliff/display.py

@@ -1,6 +1,16 @@
 """Application base class for displaying data.
 """
 import abc
+
+try:
+    from itertools import compress
+except ImportError:
+    # for py26 compat
+    from itertools import izip
+
+    def compress(data, selectors):
+        return (d for d, s in izip(data, selectors) if s)
+
 import logging
 
 import stevedore
@@ -80,3 +90,7 @@ def run(self, parsed_args):
         column_names, data = self.take_action(parsed_args)
         self.produce_output(parsed_args, column_names, data)
         return 0
+
+    @staticmethod
+    def _compress_iterable(iterable, selectors):
+        return compress(iterable, selectors)

cliff/lister.py

@@ -1,16 +1,6 @@
 """Application base class for providing a list of data as output.
 """
 import abc
-
-try:
-    from itertools import compress
-except ImportError:
-    # for py26 compat
-    from itertools import izip
-
-    def compress(data, selectors):
-        return (d for d, s in izip(data, selectors) if s)
-
 import logging
 
 from .display import DisplayCommandBase
@@ -56,7 +46,7 @@ def produce_output(self, parsed_args, column_names, data):
             # of data that the user has expressed interest in
             # seeing. We have to convert the compress() output to a
             # list so the table formatter can ask for its length.
-            data_gen = (list(compress(row, selector))
+            data_gen = (list(self._compress_iterable(row, selector))
                         for row in data)
         self.formatter.emit_list(columns_to_include,
                                  data_gen,

cliff/show.py

@@ -1,7 +1,6 @@
 """Application base class for displaying data about a single object.
 """
 import abc
-import itertools
 import logging
 
 from .display import DisplayCommandBase
@@ -38,7 +37,7 @@ def produce_output(self, parsed_args, column_names, data):
             # Set up argument to compress()
             selector = [(c in columns_to_include)
                         for c in column_names]
-            data = list(itertools.compress(data, selector))
+            data = list(self._compress_iterable(data, selector))
         self.formatter.emit_one(columns_to_include,
                                 data,
                                 self.app.stdout,

cliff/tests/test_show.py

@@ -1,5 +1,7 @@
 #!/usr/bin/env python
 
+import weakref
+
 from cliff.show import ShowOne
 
 import mock
@@ -9,15 +11,16 @@ class FauxFormatter(object):
 
     def __init__(self):
         self.args = []
+        self.obj = weakref.proxy(self)
 
-    def emit_list(self, columns, data, stdout, args):
+    def emit_one(self, columns, data, stdout, args):
         self.args.append((columns, data))
 
 
 class ExerciseShowOne(ShowOne):
 
-    def load_formatter_plugins(self):
-        self.formatters = {
+    def _load_formatter_plugins(self):
+        return {
             'test': FauxFormatter(),
         }
         return
@@ -29,21 +32,22 @@ def take_action(self, parsed_args):
         )
 
 
-# def test_formatter_args():
-#     app = mock.Mock()
-#     test_lister = ExerciseLister(app, [])
+def test_formatter_args():
+    app = mock.Mock()
+    test_show = ExerciseShowOne(app, [])
+
+    parsed_args = mock.Mock()
+    parsed_args.columns = ('Col1', 'Col2')
+    parsed_args.formatter = 'test'
 
-#     parsed_args = mock.Mock()
-#     parsed_args.columns = ('Col1', 'Col2')
-#     parsed_args.formatter = 'test'
+    test_show.run(parsed_args)
+    f = test_show._formatter_plugins['test']
+    assert len(f.args) == 1
+    args = f.args[0]
+    assert args[0] == list(parsed_args.columns)
+    data = list(args[1])
+    assert data == [('a', 'A'), ('b', 'B')]
 
-#     test_lister.run(parsed_args)
-#     f = test_lister.formatters['test']
-#     assert len(f.args) == 1
-#     args = f.args[0]
-#     assert args[0] == list(parsed_args.columns)
-#     data = list(args[1])
-#     assert data == [['a', 'A'], ['b', 'B']]
 
 def test_dict2columns():
     app = mock.Mock()