From c4eb18fa5a917fd84dd303b996ebe3c06342dccc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micka=C3=ABl=20Gu=C3=A9rin?= <mickael.guerin@people-doc.com>
Date: Mon, 28 May 2018 12:17:15 +0200
Subject: [PATCH] Percent signs escaping in templatetags

Closes https://github.com/python-babel/django-babel/issues/43

In Django >= 1.9, `%` signs are escaped to `%%` during extraction
then replaced by `%` during the rendering. [1]

The extraction now behaves in the same way.

[1] https://github.com/django/django/commit/b7508896fbe19ec2cdeb81565cd587091b6b68d0
---
 django_babel/extract.py | 18 ++++++++++++++++--
 tests/test_extract.py   | 31 +++++++++++++++++++++++++++++++
 2 files changed, 47 insertions(+), 2 deletions(-)

diff --git a/django_babel/extract.py b/django_babel/extract.py
index edb42c7..a5fec7c 100644
--- a/django_babel/extract.py
+++ b/django_babel/extract.py
@@ -11,6 +11,12 @@
     from django.utils.translation.template import (
         inline_re, block_re, endblock_re, plural_re, constant_re)
 
+try:
+    from django.utils.translation.trans_real import one_percent_re
+except ImportError:
+    # Django 1.9+
+    one_percent_re = None
+
 
 def join_tokens(tokens, trim=False):
     message = ''.join(tokens)
@@ -112,10 +118,14 @@ def extract_django(fileobj, keywords, comment_tags, options):
                 else:
                     singular.append('%%(%s)s' % t.contents)
             elif t.token_type == TOKEN_TEXT:
+                if one_percent_re:
+                    contents = one_percent_re.sub('%%', t.contents)
+                else:
+                    contents = t.contents.replace('%', '%%')
                 if inplural:
-                    plural.append(t.contents)
+                    plural.append(contents)
                 else:
-                    singular.append(t.contents)
+                    singular.append(contents)
         else:
             if t.token_type == TOKEN_BLOCK:
                 imatch = inline_re.match(t.contents)
@@ -124,6 +134,10 @@ def extract_django(fileobj, keywords, comment_tags, options):
                 if imatch:
                     g = imatch.group(1)
                     g = strip_quotes(g)
+                    if one_percent_re:
+                        g = one_percent_re.sub('%%', g)
+                    else:
+                        g = g.replace('%', '%%')
                     message_context = imatch.group(3)
                     if message_context:
                         # strip quotes
diff --git a/tests/test_extract.py b/tests/test_extract.py
index aca1a58..de3a692 100644
--- a/tests/test_extract.py
+++ b/tests/test_extract.py
@@ -218,3 +218,34 @@ def test_blocktrans_with_whitespace_trimmed(self):
         buf = BytesIO(test_tmpl)
         messages = list(extract_django(buf, default_keys, [], {}))
         self.assertEqual([(4, None, u'foo bar', [])], messages)
+
+    @pytest.mark.skipif(django.VERSION >= (1, 9),
+                        reason='%-sign escaping changed in django 1.9')
+    def test_extract_trans_percents_old_way(self):
+        """Before Django 1.9, only a signle %-sign was escaped to %%"""
+        buf = BytesIO(b'{% trans "1 %, 2 %%, 3 %%%" %}')
+        messages = list(extract_django(buf, default_keys, [], {}))
+        self.assertEqual([(1, None, u'1 %%, 2 %%, 3 %%%', [])], messages)
+
+    @pytest.mark.skipif(django.VERSION >= (1, 9),
+                        reason='%-sign escaping changed in django 1.9')
+    def test_extract_blocktrans_percents_old_way(self):
+        """Before Django 1.9, only a signle %-sign was escaped to %%"""
+        buf = BytesIO(b'{% blocktrans %}1 %, 2 %%, 3 %%%{% endblocktrans %}')
+        messages = list(extract_django(buf, default_keys, [], {}))
+        self.assertEqual([(1, None, u'1 %%, 2 %%, 3 %%%', [])], messages)
+
+    @pytest.mark.skipif(django.VERSION < (1, 9),
+                        reason='%-sign escaping changed in django 1.9')
+    def test_extract_trans_percents(self):
+        buf = BytesIO(b'{% trans "1 %, 2 %%, 3 %%%" %}')
+        messages = list(extract_django(buf, default_keys, [], {}))
+        self.assertEqual([(1, None, u'1 %%, 2 %%%%, 3 %%%%%%', [])], messages)
+
+    @pytest.mark.skipif(django.VERSION < (1, 9),
+                        reason='%-sign escaping changed in django 1.9')
+    def test_extract_blocktrans_percents(self):
+        buf = BytesIO(b'{% blocktrans %}1 %, 2 %%, 3 %%%{% endblocktrans %}')
+        messages = list(extract_django(buf, default_keys, [], {}))
+        self.assertEqual([(1, None, u'1 %%, 2 %%%%, 3 %%%%%%', [])], messages)
+