Fixes #1338, Refs #1400, #2237 -- Modified variable resolution to allow template 'if' statements to work if TEMPLATE_STRING_IF_INVALID is set. Modified unit tests to force the use of this variable, so that returning '' isn't confused with an actual failure.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@3268 bcc190cf-cafb-0310-a4f2-bffc1f526a37

3 files changed, 22 insertions, 10 deletions

diff --git a/django/template/__init__.py b/django/template/__init__.py
index 08f433fec9..993de7304e 100644
--- a/django/template/__init__.py
+++ b/django/template/__init__.py
@@ -318,7 +318,7 @@ class Parser(object):
         self.tags.update(lib.tags)
         self.filters.update(lib.filters)
 
-    def compile_filter(self,token):
+    def compile_filter(self, token):
         "Convenient wrapper for FilterExpression"
         return FilterExpression(token, self)
 
@@ -543,11 +543,14 @@ class FilterExpression(object):
             raise TemplateSyntaxError, "Could not parse the remainder: %s" % token[upto:]
         self.var, self.filters = var, filters
 
-    def resolve(self, context):
+    def resolve(self, context, ignore_failures=False):
         try:
             obj = resolve_variable(self.var, context)
         except VariableDoesNotExist:
-            obj = settings.TEMPLATE_STRING_IF_INVALID
+            if ignore_failures:
+                return None
+            else:
+                return settings.TEMPLATE_STRING_IF_INVALID
         for func, args in self.filters:
             arg_vals = []
             for lookup, arg in args:
diff --git a/django/template/context.py b/django/template/context.py
index 44a97f95a8..6d9efdc7ec 100644
--- a/django/template/context.py
+++ b/django/template/context.py
@@ -37,7 +37,7 @@ class Context(object):
         for d in self.dicts:
             if d.has_key(key):
                 return d[key]
-        return settings.TEMPLATE_STRING_IF_INVALID
+        raise KeyError(key)
 
     def __delitem__(self, key):
         "Delete a variable from the current context"
@@ -49,7 +49,7 @@ class Context(object):
                 return True
         return False
 
-    def get(self, key, otherwise):
+    def get(self, key, otherwise=None):
         for d in self.dicts:
             if d.has_key(key):
                 return d[key]
diff --git a/django/template/defaulttags.py b/django/template/defaulttags.py
index 88cb5f68be..0a4fe33d82 100644
--- a/django/template/defaulttags.py
+++ b/django/template/defaulttags.py
@@ -45,7 +45,10 @@ class FirstOfNode(Node):
 
     def render(self, context):
         for var in self.vars:
-            value = resolve_variable(var, context)
+            try:
+                value = resolve_variable(var, context)
+            except VariableDoesNotExist:
+                continue
             if value:
                 return str(value)
         return ''
@@ -144,8 +147,14 @@ class IfEqualNode(Node):
         return "<IfEqualNode>"
 
     def render(self, context):
-        val1 = resolve_variable(self.var1, context)
-        val2 = resolve_variable(self.var2, context)
+        try:
+            val1 = resolve_variable(self.var1, context)
+        except VariableDoesNotExist:
+            val1 = None
+        try:
+            val2 = resolve_variable(self.var2, context)
+        except VariableDoesNotExist:
+            val2 = None
         if (self.negate and val1 != val2) or (not self.negate and val1 == val2):
             return self.nodelist_true.render(context)
         return self.nodelist_false.render(context)
@@ -177,7 +186,7 @@ class IfNode(Node):
         if self.link_type == IfNode.LinkTypes.or_:
             for ifnot, bool_expr in self.bool_exprs:
                 try:
-                    value = bool_expr.resolve(context)
+                    value = bool_expr.resolve(context, True)
                 except VariableDoesNotExist:
                     value = None
                 if (value and not ifnot) or (ifnot and not value):
@@ -186,7 +195,7 @@ class IfNode(Node):
         else:
             for ifnot, bool_expr in self.bool_exprs:
                 try:
-                    value = bool_expr.resolve(context)
+                    value = bool_expr.resolve(context, True)
                 except VariableDoesNotExist:
                     value = None
                 if not ((value and not ifnot) or (ifnot and not value)):