Add support for "trimmed" blocktrans content

Author: Rob Hudson

django_babel/extract.py

@@ -5,9 +5,32 @@
     # Django 1.8 moved most stuff to .base
     from django.template.base import Lexer, TOKEN_TEXT, TOKEN_VAR, TOKEN_BLOCK
 
+try:
+    from django.utils.translation import trim_whitespace as trim_django
+except ImportError:
+    trim_django = False
+
+from django.utils.encoding import smart_text
 from django.utils.translation.trans_real import (
     inline_re, block_re, endblock_re, plural_re, constant_re)
-from django.utils.encoding import smart_text
+
+
+def trim_whitespace(string):
+    """Trim whitespace.
+
+    This is only supported in Django>=1.7. This method help in cases of older
+    Django versions.
+    """
+    if trim_django:
+        return trim_django(string)
+    return string
+
+
+def join_tokens(tokens, trim=False):
+    message = ''.join(tokens)
+    if trim:
+        message = trim_whitespace(message)
+    return message
 
 
 def extract_django(fileobj, keywords, comment_tags, options):
@@ -25,6 +48,7 @@ def extract_django(fileobj, keywords, comment_tags, options):
     """
     intrans = False
     inplural = False
+    trimmed = False
     message_context = None
     singular = []
     plural = []
@@ -53,31 +77,31 @@ def extract_django(fileobj, keywords, comment_tags, options):
                                 lineno,
                                 'npgettext',
                                 [smart_text(message_context),
-                                 smart_text(u''.join(singular)),
-                                 smart_text(u''.join(plural))],
+                                 smart_text(join_tokens(singular, trimmed)),
+                                 smart_text(join_tokens(plural, trimmed))],
                                 [],
                             )
                         else:
                             yield (
                                 lineno,
                                 'ngettext',
-                                (smart_text(u''.join(singular)),
-                                 smart_text(u''.join(plural))),
+                                (smart_text(join_tokens(singular, trimmed)),
+                                 smart_text(join_tokens(plural, trimmed))),
                                 [])
                     else:
                         if message_context:
                             yield (
                                 lineno,
                                 'pgettext',
                                 [smart_text(message_context),
-                                 smart_text(u''.join(singular))],
+                                 smart_text(join_tokens(singular, trimmed))],
                                 [],
                             )
                         else:
                             yield (
                                 lineno,
                                 None,
-                                smart_text(u''.join(singular)),
+                                smart_text(join_tokens(singular, trimmed)),
                                 [])
 
                     intrans = False
@@ -131,6 +155,7 @@ def extract_django(fileobj, keywords, comment_tags, options):
                         yield lineno, None, smart_text(fmatch), []
                     intrans = True
                     inplural = False
+                    trimmed = 'trimmed' in t.split_contents()
                     singular = []
                     plural = []
                 elif cmatches:

tests/test_extract.py

@@ -6,6 +6,7 @@
 from babel.messages import extract
 from babel._compat import BytesIO
 
+import django
 from django_babel.extract import extract_django
 
 
@@ -199,3 +200,21 @@ def test_extract_context_in_plural_block(self):
             [(1, 'npgettext', [u'banana', u'%(foo)s', u'%(bar)s'], [])],
             messages,
         )
+
+    def test_blocktrans_with_whitespace_not_trimmed(self):
+        test_tmpl = (
+            b'{% blocktrans %}\n\tfoo\n\tbar\n{% endblocktrans %}'
+        )
+        buf = BytesIO(test_tmpl)
+        messages = list(extract_django(buf, default_keys, [], {}))
+        self.assertEqual([(4, None, u'\n\tfoo\n\tbar\n', [])], messages)
+
+    @pytest.mark.skipif(django.VERSION < (1, 7),
+                        reason='Trimmed whitespace is a Django >= 1.7 feature')
+    def test_blocktrans_with_whitespace_trimmed(self):
+        test_tmpl = (
+            b'{% blocktrans trimmed %}\n\tfoo\n\tbar\n{% endblocktrans %}'
+        )
+        buf = BytesIO(test_tmpl)
+        messages = list(extract_django(buf, default_keys, [], {}))
+        self.assertEqual([(4, None, u'foo bar', [])], messages)