Fixed #12199 -- Added the ability to use "as" with the firstof template tag.

django/template/defaulttags.py

@@ -110,14 +110,19 @@ class FilterNode(Node):
 
 
 class FirstOfNode(Node):
-    def __init__(self, variables):
+    def __init__(self, variables, asvar=None):
         self.vars = variables
+        self.asvar = asvar
 
     def render(self, context):
         for var in self.vars:
             value = var.resolve(context, True)
             if value:
-                return render_value_in_context(value, context)
+                first = render_value_in_context(value, context)
+                if self.asvar:
+                    context[self.asvar] = first
+                    return ''
+                return first
         return ''
 
 
@@ -748,7 +753,7 @@ def firstof(parser, token):
 
     Sample usage::
 
-        {% firstof var1 var2 var3 %}
+        {% firstof var1 var2 var3 as myvar %}
 
     This is equivalent to::
 
@@ -779,9 +784,14 @@ def firstof(parser, token):
 
     """
     bits = token.split_contents()[1:]
+    asvar = None
     if len(bits) < 1:
         raise TemplateSyntaxError("'firstof' statement requires at least one argument")
-    return FirstOfNode([parser.compile_filter(bit) for bit in bits])
+
+    if len(bits) >= 2 and bits[-2] == 'as':
+        asvar = bits[-1]
+        bits = bits[:-2]
+    return FirstOfNode([parser.compile_filter(bit) for bit in bits], asvar)
 
 
 @register.tag('for')

docs/ref/templates/builtins.txt

@@ -285,6 +285,13 @@ Or if only some variables should be escaped, you can use::
 
     {% firstof var1 var2|safe var3 "<strong>fallback value</strong>"|safe %}
 
+You can use the syntax ``{% firstof var1 var2 var3 as value %}`` to store the
+output inside a variable.
+
+.. versionadded:: 1.9
+
+    The "as" syntax was added.
+
 .. templatetag:: for
 
 for

docs/releases/1.9.txt

@@ -208,6 +208,9 @@ Templates
 * A warning will now be logged for missing context variables. These messages
   will be logged to the :ref:`django.template <django-template-logger>` logger.
 
+* The :ttag:`firstof` template tag supports storing the output in a variable
+  using 'as'.
+
 Requests and Responses
 ^^^^^^^^^^^^^^^^^^^^^^
 

tests/template_tests/syntax_tests/test_firstof.py

@@ -81,3 +81,10 @@ class FirstOfTagTests(SimpleTestCase):
     def test_firstof14(self):
         output = self.engine.render_to_string('firstof14', {'a': '<'})
         self.assertEqual(output, '<')
+
+    @setup({'firstof15': '{% firstof a b c as myvar %}'})
+    def test_firstof15(self):
+        ctx = {'a': 0, 'b': 2, 'c': 3}
+        output = self.engine.render_to_string('firstof15', ctx)
+        self.assertEqual(ctx['myvar'], '2')
+        self.assertEqual(output, '')