From 2169c85dbb011beb411a5c37ebc8d700b0984ce8 Mon Sep 17 00:00:00 2001
From: spiq <none@none>
Date: Fri, 4 Mar 2011 17:23:18 +0200
Subject: [PATCH] FomrParser now implements a work around for empty values in a
 list

---
 djangorestframework/content.py |  5 ++++-
 djangorestframework/parsers.py | 25 ++++++++++++++++++++-----
 2 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/djangorestframework/content.py b/djangorestframework/content.py
index dd40f8f1a..fe1a56d93 100644
--- a/djangorestframework/content.py
+++ b/djangorestframework/content.py
@@ -49,6 +49,9 @@ class SocketFile(File):
 class OverloadedContentMixin(ContentMixin):
     """HTTP request content behaviour that also allows arbitrary content to be tunneled in form data."""
     
+    #TODO: test PUT
+    #TODO: rewrite cleaner
+
     """The name to use for the content override field in the POST form."""
     CONTENT_PARAM = '_content'
 
@@ -59,7 +62,7 @@ class OverloadedContentMixin(ContentMixin):
         """If the request contains content return a tuple of (content_type, content) otherwise return None.
         Note that content_type may be None if it is unset."""
         if not request.META.get('CONTENT_LENGTH', None) and not request.META.get('TRANSFER_ENCODING', None):
-            return None
+            return None # TODO : Breaks, because determine_content should return a tuple.
         content_type = request.META.get('CONTENT_TYPE', None)
 
         if (request.method == 'POST' and self.CONTENT_PARAM and
diff --git a/djangorestframework/parsers.py b/djangorestframework/parsers.py
index c334f7292..38f3db4b4 100644
--- a/djangorestframework/parsers.py
+++ b/djangorestframework/parsers.py
@@ -79,11 +79,11 @@ class XMLParser(BaseParser):
     media_type = 'application/xml'
 
 class DataFlatener(object):
+#TODO : document + test
 
     def flatten_data(self, data):
         """Given a data dictionary ``{<attr_name>: <value_list>}``, returns a flattened dictionary according to :meth:`FormParser.is_a_list`.
         """
-        #TODO : document + test
         flatdata = dict()
         for attr_name, attr_value in data.items():
             if self.is_a_list(attr_name):
@@ -100,27 +100,32 @@ class DataFlatener(object):
 
     def is_a_list(self, attr_name):
         """ """
-        #TODO: document
         return False
 
 class FormParser(BaseParser, DataFlatener):
     """The default parser for form data.
     Return a dict containing a single value for each non-reserved parameter.
     """
+    # TODO: document flatening
     # TODO: writing tests for PUT files + normal data
+    # TODO: document EMPTY workaround
     media_type = 'application/x-www-form-urlencoded'
 
+    EMPTY_VALUE = 'EMPTY'
+
     def parse(self, input):
         request = self.resource.request
 
         if request.method == 'PUT':
             data = parse_qs(input)
-
-        if request.method == 'POST':
+        elif request.method == 'POST':
             # Django has already done the form parsing for us.
             data = request.POST
 
+        # Flatening data and removing EMPTY_VALUEs from the lists
         data = self.flatten_data(data)
+        for key in filter(lambda k: self.is_a_list(k), data):
+            self.remove_empty_val(data[key])
 
         # Strip any parameters that we are treating as reserved
         for key in data:
@@ -128,6 +133,16 @@ class FormParser(BaseParser, DataFlatener):
                 data.pop(key)
         return data
 
+    def remove_empty_val(self, val_list):
+        """ """
+        while(1): # Because there might be several times EMPTY_VALUE in the list
+            try: 
+                ind = val_list.index(self.EMPTY_VALUE)
+            except ValueError:
+                break
+            else:
+                val_list.pop(ind) 
+
 # TODO: Allow parsers to specify multiple media_types
 class MultipartParser(BaseParser, DataFlatener):
     media_type = 'multipart/form-data'
@@ -139,12 +154,12 @@ class MultipartParser(BaseParser, DataFlatener):
             upload_handlers = request._get_upload_handlers()
             django_mpp = DjangoMPParser(request.META, StringIO(input), upload_handlers)
             data, files = django_mpp.parse()
-
         elif request.method == 'POST':
             # Django has already done the form parsing for us.
             data = request.POST
             files = request.FILES
 
+        # Flatening data, files and combining them
         data = self.flatten_data(data)
         files = self.flatten_data(files)
         data.update(files)