adding support for implicit invalid vote (#64)

tally_methods/tally.py

@@ -16,7 +16,10 @@
 # along with tally-methods.  If not, see <http://www.gnu.org/licenses/>.
 
 
-from tally_methods.voting_systems.base import get_voting_system_by_id, BlankVoteException
+from tally_methods.voting_systems.base import (
+    get_voting_system_by_id,
+    BlankVoteException
+)
 
 import copy
 import glob

tally_methods/voting_systems/base.py

@@ -181,11 +181,12 @@ def parse_vote(
         '''
         raw_ballot = self.decoder.decode_from_int(int_ballot)
         decoded_ballot = self.decoder.decode_raw_ballot(raw_ballot)
+        exception = None
 
         # detect if the ballot was marked as invalid, even if there's no 
         # explicit invalid answer
         if raw_ballot['choices'][0] > 0:
-            raise Exception()
+            exception = 'explicit'
 
         non_blank_unwithdrawed_answers = None
         if self.custom_subparser is None:
@@ -208,8 +209,8 @@ def parse_vote(
                 withdrawals
             )
 
-        if len(non_blank_unwithdrawed_answers) == 0:
-            raise BlankVoteException()
+        if len(non_blank_unwithdrawed_answers) == 0 and exception is None:
+            exception = 'blank'
 
         # check that no write-in is repeated or else it's an invalid vote
         write_in_answers = [
@@ -220,15 +221,15 @@ def parse_vote(
                 len(answer['text']) > 0
             )
         ]
-        if len(write_in_answers) != len(set(write_in_answers)):
-            raise Exception()
+        if len(write_in_answers) != len(set(write_in_answers)) and exception != 'explicit':
+            exception = 'implicit'
 
         # detect and deal with different types of invalid votes
         if (
             len(non_blank_unwithdrawed_answers) < question['min'] or 
             len(set(non_blank_unwithdrawed_answers)) != len(non_blank_unwithdrawed_answers)
-        ):
-            raise Exception()
+        ) and exception != 'explicit':
+            exception = 'implicit'
 
         truncate = False
         if len(non_blank_unwithdrawed_answers) > question['max']:
@@ -239,8 +240,8 @@ def parse_vote(
                 non_blank_unwithdrawed_answers = \
                     non_blank_unwithdrawed_answers[:question['max']]
                 truncate = True
-            else:
-                raise Exception()
+            elif exception != 'explicit':
+                exception = 'implicit'
 
         # if panachage is disabled and vote is for answer of multiple categories
         # then it's an invalid vote
@@ -255,10 +256,20 @@ def parse_vote(
             ]
             if truncate:
                 filtered_answer_categories = filtered_answer_categories[:question['max']]
-            if len(set(filtered_answer_categories)) > 1:
-                raise Exception()
+            if (
+                len(set(filtered_answer_categories)) > 1 and
+                exception != 'explicit'
+            ):
+                exception = 'implicit'
 
-        return non_blank_unwithdrawed_answers
+        if exception is None:
+            return non_blank_unwithdrawed_answers
+        elif exception == 'blank':
+            raise BlankVoteException(non_blank_unwithdrawed_answers)
+        elif exception == 'explicit':
+            raise ExplicitInvalidVoteException(non_blank_unwithdrawed_answers)
+        elif exception == 'implicit':
+            raise ImplicitInvalidVoteException(non_blank_unwithdrawed_answers)
 
     def add_vote(self, voter_answers, questions, is_delegated):
         '''
@@ -354,3 +365,19 @@ def get_log(self):
 
 class BlankVoteException(Exception):
     pass
+
+class ExplicitInvalidVoteException(Exception):
+
+    ballot = None
+
+    def __init__(self, ballot):
+        self.ballot = ballot
+        super().__init__()
+
+class ImplicitInvalidVoteException(Exception):
+
+    ballot = None
+
+    def __init__(self, ballot):
+        self.ballot = ballot
+        super().__init__()

tally_methods/voting_systems/borda.py

@@ -17,6 +17,7 @@
     BaseVotingSystem, 
     BaseTally, 
     WeightedChoice, 
+    ImplicitInvalidVoteException,
     get_key
 )
 
@@ -52,6 +53,7 @@ class BordaTally(BaseTally):
     def init(self):
         def custom_subparser(decoded_ballot, question, withdrawals):
             answers = set()
+            exception = None
 
             if 'bordas-max-points' not in question:
                 max_points = question['max']
@@ -78,7 +80,7 @@ def custom_subparser(decoded_ballot, question, withdrawals):
             ]
             # - no position is repeated
             if len(selection) != len(set(selection)):
-                raise Exception()
+                exception = 'implicit'
 
             selection_sorted = sorted(selection)
             should_be_selection_sorted = [
@@ -87,10 +89,13 @@ def custom_subparser(decoded_ballot, question, withdrawals):
             ]
             # - no missing position in-between
             if selection_sorted != should_be_selection_sorted:
-                raise Exception()
+                exception = 'implicit'
 
-
-            return frozenset(answers)
+            ret_value = frozenset(answers)
+            if exception is None:
+                return ret_value
+            else:
+                raise ImplicitInvalidVoteException(ret_value)
 
         self.custom_subparser = custom_subparser
 

tally_methods/voting_systems/borda_custom.py

@@ -17,6 +17,7 @@
     BaseVotingSystem, 
     BaseTally, 
     WeightedChoice, 
+    ImplicitInvalidVoteException,
     get_key
 )
 from .borda import BordaTally
@@ -53,8 +54,8 @@ class BordaCustomTally(BordaTally):
     def init(self):
         def custom_subparser(decoded_ballot, question, withdrawals):
             answers = set()
-
             weights = question['borda_custom_weights']
+            exception = None
 
             for answer in decoded_ballot["answers"]:
                 if answer['selected'] < 0 or answer['id'] in withdrawals:
@@ -76,7 +77,7 @@ def custom_subparser(decoded_ballot, question, withdrawals):
             ]
             # - no position is repeated
             if len(selection) != len(set(selection)):
-                raise Exception()
+                exception = 'implicit'
 
             selection_sorted = sorted(selection)
             should_be_selection_sorted = [
@@ -85,8 +86,12 @@ def custom_subparser(decoded_ballot, question, withdrawals):
             ]
             # - no missing position in-between
             if selection_sorted != should_be_selection_sorted:
-                raise Exception()
+                exception = 'implicit'
 
-            return frozenset(answers)
+            ret_value = frozenset(answers)
+            if exception is None:
+                return ret_value
+            else:
+                raise ImplicitInvalidVoteException(ret_value)
 
         self.custom_subparser = custom_subparser

tally_methods/voting_systems/borda_nauru.py

@@ -16,7 +16,8 @@
 from .base import (
     BaseVotingSystem, 
     BaseTally, 
-    WeightedChoice, 
+    WeightedChoice,
+    ImplicitInvalidVoteException,
     get_key
 )
 from .borda import BordaTally
@@ -50,6 +51,7 @@ class BordaNauruTally(BordaTally):
     def init(self):
         def custom_subparser(decoded_ballot, question, withdrawals):
             answers = set()
+            exception = None
 
             for answer in decoded_ballot["answers"]:
                 if answer['selected'] < 0 or answer['id'] in withdrawals:
@@ -71,7 +73,7 @@ def custom_subparser(decoded_ballot, question, withdrawals):
             ]
             # - no position is repeated
             if len(selection) != len(set(selection)):
-                raise Exception()
+                exception = 'implicit'
 
             selection_sorted = sorted(selection)
             should_be_selection_sorted = [
@@ -80,8 +82,12 @@ def custom_subparser(decoded_ballot, question, withdrawals):
             ]
             # - no missing position in-between
             if selection_sorted != should_be_selection_sorted:
-                raise Exception()
+                exception = 'implicit'
 
-            return frozenset(answers)
+            ret_value = frozenset(answers)
+            if exception is None:
+                return ret_value
+            else:
+                raise ImplicitInvalidVoteException(ret_value)
 
         self.custom_subparser = custom_subparser