Fixed #6295 -- Made the {% for %} tag a bit more efficient by creating a single…

Fixed #6295 -- Made the {% for %} tag a bit more efficient by creating a single context dictionary rather than recreating it each time through the loop. Thanks, Ned Batchelder

git-svn-id: http://code.djangoproject.com/svn/django/trunk@6981 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/template/defaulttags.py

@@ -125,19 +125,20 @@ class ForNode(Node):
         if self.is_reversed:
             values = reversed(values)
         unpack = len(self.loopvars) > 1
+        # Create a forloop value in the context.  We'll update counters on each
+        # iteration just below.
+        loop_dict = context['forloop'] = {'parentloop': parentloop}
         for i, item in enumerate(values):
-            context['forloop'] = {
-                # Shortcuts for current loop iteration number.
-                'counter0': i,
-                'counter': i+1,
-                # Reverse counter iteration numbers.
-                'revcounter': len_values - i,
-                'revcounter0': len_values - i - 1,
-                # Boolean values designating first and last times through loop.
-                'first': (i == 0),
-                'last': (i == len_values - 1),
-                'parentloop': parentloop,
-            }
+            # Shortcuts for current loop iteration number.
+            loop_dict['counter0'] = i
+            loop_dict['counter'] = i+1
+            # Reverse counter iteration numbers.
+            loop_dict['revcounter'] = len_values - i
+            loop_dict['revcounter0'] = len_values - i - 1
+            # Boolean values designating first and last times through loop.
+            loop_dict['first'] = (i == 0)
+            loop_dict['last'] = (i == len_values - 1)
+
             if unpack:
                 # If there are multiple loop variables, unpack the item into
                 # them.

tests/regressiontests/templates/tests.py

@@ -441,6 +441,8 @@ class Templates(unittest.TestCase):
             'for-tag-vars02': ("{% for val in values %}{{ forloop.counter0 }}{% endfor %}", {"values": [6, 6, 6]}, "012"),
             'for-tag-vars03': ("{% for val in values %}{{ forloop.revcounter }}{% endfor %}", {"values": [6, 6, 6]}, "321"),
             'for-tag-vars04': ("{% for val in values %}{{ forloop.revcounter0 }}{% endfor %}", {"values": [6, 6, 6]}, "210"),
+            'for-tag-vars05': ("{% for val in values %}{% if forloop.first %}f{% else %}x{% endif %}{% endfor %}", {"values": [6, 6, 6]}, "fxx"),
+            'for-tag-vars06': ("{% for val in values %}{% if forloop.last %}l{% else %}x{% endif %}{% endfor %}", {"values": [6, 6, 6]}, "xxl"),
             'for-tag-unpack01': ("{% for key,value in items %}{{ key }}:{{ value }}/{% endfor %}", {"items": (('one', 1), ('two', 2))}, "one:1/two:2/"),
             'for-tag-unpack03': ("{% for key, value in items %}{{ key }}:{{ value }}/{% endfor %}", {"items": (('one', 1), ('two', 2))}, "one:1/two:2/"),
             'for-tag-unpack04': ("{% for key , value in items %}{{ key }}:{{ value }}/{% endfor %}", {"items": (('one', 1), ('two', 2))}, "one:1/two:2/"),