Drop use of babel

We were simply using this to get a list of language codes. Turns out
Python provides a way to do this already via the 'locale' module, which
provides all of the locales we care about [1]. Use this.

[1] https://github.com/python/cpython/blob/3.5/Lib/locale.py

Change-Id: Id6dce33fdbe3fc537dfe28d5cc604985b3347405
Signed-off-by: Stephen Finucane <stephenfin@redhat.com>

4 files changed, 26 insertions, 68 deletions

diff --git a/lower-constraints.txt b/lower-constraints.txt
index 9fadd9e..b3bca92 100644
--- a/lower-constraints.txt
+++ b/lower-constraints.txt
@@ -1,6 +1,5 @@
 alabaster==0.7.10
 appdirs==1.3.0
-Babel==2.3.4
 bandit==1.4.0
 coverage==4.0
 debtcollector==1.2.0
diff --git a/oslo_i18n/_gettextutils.py b/oslo_i18n/_gettextutils.py
index 00028a6..bc6946f 100644
--- a/oslo_i18n/_gettextutils.py
+++ b/oslo_i18n/_gettextutils.py
@@ -19,10 +19,9 @@
 
 import copy
 import gettext
+import locale
 import os
 
-from babel import localedata
-
 from oslo_i18n import _factory
 from oslo_i18n import _locale
 
@@ -62,43 +61,20 @@ def get_available_languages(domain):
         return copy.copy(_AVAILABLE_LANGUAGES[domain])
 
     localedir = os.environ.get(_locale.get_locale_dir_variable_name(domain))
-    find = lambda x: gettext.find(domain,
-                                  localedir=localedir,
-                                  languages=[x])
+
+    def find(x):
+        return gettext.find(domain, localedir=localedir, languages=[x])
 
     # NOTE(mrodden): en_US should always be available (and first in case
     # order matters) since our in-line message strings are en_US
     language_list = ['en_US']
-    locale_identifiers = localedata.locale_identifiers()
-    language_list.extend(language for language in locale_identifiers
-                         if find(language))
-
-    # In Babel 1.3, locale_identifiers() doesn't list some OpenStack supported
-    # locales (e.g. 'zh_CN', and 'zh_TW') so we add the locales explicitly if
-    # necessary so that they are listed as supported.
-    aliases = {'zh': 'zh_CN',
-               'zh_Hant_HK': 'zh_HK',
-               'zh_Hant': 'zh_TW',
-               'fil': 'tl_PH'}
-    language_list.extend(alias for locale, alias in aliases.items()
-                         if (locale in language_list and
-                             alias not in language_list))
-
-    language_list.extend(alias for locale, alias in aliases.items()
-                         if (locale not in language_list and
-                             find(alias)))
-
-    # In webob.acceptparse, the best_match is just match the first element in
-    # the language_list, so make the precise element in front
-    result = ['en_US']
-    for i in language_list[1:]:
-        if '_' in i:
-            result.insert(1, i)
-        else:
-            result.append(i)
-
-    _AVAILABLE_LANGUAGES[domain] = result
-    return copy.copy(result)
+    locale_identifiers = set(locale.windows_locale.values())
+    language_list.extend(
+        language for language in locale_identifiers if find(language)
+    )
+
+    _AVAILABLE_LANGUAGES[domain] = language_list
+    return copy.copy(language_list)
 
 
 _original_find = gettext.find
diff --git a/oslo_i18n/tests/test_gettextutils.py b/oslo_i18n/tests/test_gettextutils.py
index 0592542..49f95e1 100644
--- a/oslo_i18n/tests/test_gettextutils.py
+++ b/oslo_i18n/tests/test_gettextutils.py
@@ -18,7 +18,6 @@ import gettext
 import logging
 from unittest import mock
 
-from babel import localedata
 from oslotest import base as test_base
 import six
 
@@ -75,29 +74,15 @@ class GettextTest(test_base.BaseTestCase):
                 self.assertIn('_', six.moves.builtins.__dict__)
 
     def test_get_available_languages(self):
-        # All the available languages for which locale data is available
-        def _mock_locale_identifiers():
-            # 'zh', 'zh_Hant'. 'zh_Hant_HK', 'fil' all have aliases
-            # missing from babel but we add them in _gettextutils, we
-            # test that here too
-            return ['zh', 'es', 'nl', 'fr', 'zh_Hant', 'zh_Hant_HK', 'fil']
-
-        mock_patcher = mock.patch.object(localedata,
-                                         'list' if hasattr(localedata, 'list')
-                                         else 'locale_identifiers',
-                                         _mock_locale_identifiers)
-        mock_patcher.start()
-        self.addCleanup(mock_patcher.stop)
-
         # Only the languages available for a specific translation domain
         def _mock_gettext_find(domain, localedir=None, languages=None, all=0):
             languages = languages or []
             if domain == 'domain_1':
-                return 'translation-file' if any(x in ['zh', 'es', 'fil']
-                                                 for x in languages) else None
+                if any(x in ['en_GB', 'es_ES', 'fil_PH'] for x in languages):
+                    return 'translation-file'
             elif domain == 'domain_2':
-                return 'translation-file' if any(x in ['fr', 'zh_Hant']
-                                                 for x in languages) else None
+                if any(x in ['fr_FR', 'zh_HK'] for x in languages):
+                    return 'translation-file'
             return None
         mock_patcher = mock.patch.object(gettext, 'find', _mock_gettext_find)
         mock_patcher.start()
@@ -110,20 +95,19 @@ class GettextTest(test_base.BaseTestCase):
         # and it should also always be the first element since order matters
         domain_1_languages = _gettextutils.get_available_languages('domain_1')
         domain_2_languages = _gettextutils.get_available_languages('domain_2')
-        self.assertEqual('en_US', domain_1_languages[0])
-        self.assertEqual('en_US', domain_2_languages[0])
+
         # The domain languages should be included after en_US with
         # with their respective aliases when it applies
-        self.assertEqual(6, len(domain_1_languages))
-        self.assertIn('zh', domain_1_languages)
-        self.assertIn('zh_CN', domain_1_languages)
-        self.assertIn('es', domain_1_languages)
-        self.assertIn('fil', domain_1_languages)
-        self.assertIn('tl_PH', domain_1_languages)
-        self.assertEqual(4, len(domain_2_languages))
-        self.assertIn('fr', domain_2_languages)
-        self.assertIn('zh_Hant', domain_2_languages)
-        self.assertIn('zh_TW', domain_2_languages)
+        self.assertEqual('en_US', domain_1_languages[0])
+        self.assertEqual('en_US', domain_2_languages[0])
+
+        self.assertEqual(4, len(domain_1_languages), domain_1_languages)
+        self.assertEqual(
+            {'en_US', 'fil_PH', 'en_GB', 'es_ES'}, set(domain_1_languages),
+        )
+        self.assertEqual(3, len(domain_2_languages), domain_2_languages)
+        self.assertEqual({'en_US', 'fr_FR', 'zh_HK'}, set(domain_2_languages))
+
         self.assertEqual(2, len(_gettextutils._AVAILABLE_LANGUAGES))
         # Now test an unknown domain, only en_US should be included
         unknown_domain_languages = _gettextutils.get_available_languages('huh')
diff --git a/requirements.txt b/requirements.txt
index bad16ca..a072ac0 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -3,5 +3,4 @@
 # process, which may cause wedges in the gate later.
 
 pbr!=2.1.0,>=2.0.0 # Apache-2.0
-Babel!=2.4.0,>=2.3.4 # BSD
 six>=1.10.0 # MIT