Merge branch 'jjardon/python_compatibility_fixes' of ssh://git.baserock.org/baserock/baserock/morph

This includes the following fixups:
  - altering the bootstrap script to install ordereddict and simplejson.
  - Adding a comment to clarify that it is intentional to use simplejson
    if collections does not have OrderedDict
  - Amending the copyright years to include 2013

2 files changed, 41 insertions, 55 deletions

diff --git a/morphlib/morph2.py b/morphlib/morph2.py
index 73d55d1d..4fdf7ba4 100644
--- a/morphlib/morph2.py
+++ b/morphlib/morph2.py
@@ -1,4 +1,4 @@
-# Copyright (C) 2012  Codethink Limited
+# Copyright (C) 2012-2013  Codethink Limited
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -14,16 +14,19 @@
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 
 
-import sys
-have_python27 = sys.version_info >= (2,7)
-
-import collections
-if not hasattr(collections, 'OrderedDict'): # pragma: no cover
-    collections.OrderedDict = dict
 import copy
-import json
 import re
 
+# It is intentional that if collections does not have OrderedDict that
+# simplejson is also used in preference to json, as OrderedDict became
+# a member of collections in the same release json got its object_pairs_hook
+try: # pragma: no cover
+    from collections import OrderedDict
+    import json
+except ImportError: # pragma: no cover
+    from ordereddict import OrderedDict
+    import simplejson as json
+
 
 class Morphology(object):
 
@@ -58,19 +61,8 @@ class Morphology(object):
         ]
     }
 
-    if have_python27: # pragma: no cover
-        @staticmethod
-        def _order_keys(pairs):
-            result = collections.OrderedDict()
-            for k,v in pairs:
-                result[k] = v
-            return result
-
     def __init__(self, text):
-        if have_python27: # pragma: no cover
-            self._dict = json.loads(text, object_pairs_hook=self._order_keys)
-        else: # pragma: no cover
-            self._dict = json.loads(text)
+        self._dict = json.loads(text, object_pairs_hook=OrderedDict)
         self._set_defaults()
         self._validate_children()
 
@@ -158,7 +150,7 @@ class Morphology(object):
         # Recreate dict without the empty default values, with a few kind
         # specific hacks to try and edit standard morphologies as
         # non-destructively as possible
-        as_dict = collections.OrderedDict()
+        as_dict = OrderedDict()
         for key in self.keys():
             if self['kind'] == 'stratum' and key == 'chunks':
                 value = copy.copy(self[key])
diff --git a/morphlib/morph2_tests.py b/morphlib/morph2_tests.py
index baa6f724..756873a0 100644
--- a/morphlib/morph2_tests.py
+++ b/morphlib/morph2_tests.py
@@ -1,4 +1,4 @@
-# Copyright (C) 2012  Codethink Limited
+# Copyright (C) 2012-2013  Codethink Limited
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -14,9 +14,6 @@
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 
 
-import sys
-have_python27 = sys.version_info >= (2,7)
-
 import StringIO
 import unittest
 
@@ -202,9 +199,8 @@ class MorphologyTests(unittest.TestCase):
                           Morphology,
                           text)
 
-    if have_python27:
-        def test_writing_preserves_field_order(self):
-            text = '''{
+    def test_writing_preserves_field_order(self):
+        text = '''{
     "kind": "system",
     "disk-size": 1073741824,
     "description": "Some text",
@@ -223,19 +219,18 @@ class MorphologyTests(unittest.TestCase):
         }
     ]
 }'''
-            morphology = Morphology(text)
-            output = StringIO.StringIO()
-            morphology.write_to_file(output)
+        morphology = Morphology(text)
+        output = StringIO.StringIO()
+        morphology.write_to_file(output)
 
-            text_lines = text.splitlines()
-            output_lines = output.getvalue().splitlines()
+        text_lines = text.splitlines()
+        output_lines = output.getvalue().splitlines()
 
-            # Verify that input and output are equal.
-            self.assertEqual(text_lines, output_lines)
+        # Verify that input and output are equal.
+        self.assertEqual(text_lines, output_lines)
 
-    if have_python27:
-        def test_writing_stratum_morphology_preserves_chunk_order(self):
-            text = '''{
+    def test_writing_stratum_morphology_preserves_chunk_order(self):
+        text = '''{
     "kind": "stratum",
     "chunks": [
         {
@@ -252,30 +247,29 @@ class MorphologyTests(unittest.TestCase):
         }
     ]
 }'''
-            morphology = Morphology(text)
-            output = StringIO.StringIO()
-            morphology.write_to_file(output)
+        morphology = Morphology(text)
+        output = StringIO.StringIO()
+        morphology.write_to_file(output)
 
-            text_lines = text.splitlines()
-            output_lines = output.getvalue().splitlines()
+        text_lines = text.splitlines()
+        output_lines = output.getvalue().splitlines()
 
-            # Verify that input and output are equal.
-            self.assertEqual(text_lines, output_lines)
+        # Verify that input and output are equal.
+        self.assertEqual(text_lines, output_lines)
 
-    if have_python27:
-        def test_writing_preserves_disk_size(self):
-            text = '''{
+    def test_writing_preserves_disk_size(self):
+        text = '''{
     "kind": "system",
     "disk-size": "1g",
     "arch": "x86_64",
     "system-kind": "syslinux-disk"
 }'''
-            morphology = Morphology(text)
-            output = StringIO.StringIO()
-            morphology.write_to_file(output)
+        morphology = Morphology(text)
+        output = StringIO.StringIO()
+        morphology.write_to_file(output)
 
-            text_lines = text.splitlines()
-            output_lines = output.getvalue().splitlines()
+        text_lines = text.splitlines()
+        output_lines = output.getvalue().splitlines()
 
-            # Verify that in- and output are the same.
-            self.assertEqual(text_lines, output_lines)
+        # Verify that in- and output are the same.
+        self.assertEqual(text_lines, output_lines)