Cap unfunded dues

sql/branch.sql

@@ -0,0 +1,14 @@
+BEGIN;
+    UPDATE payment_instructions SET due = 0 WHERE amount = 0 AND due != 0;
+
+    UPDATE payment_instructions pi
+       SET due = 0
+     WHERE due > 9.41
+       AND (                          -- Doesn't have a valid CC
+             SELECT COUNT(*)
+               FROM current_exchange_routes r
+              WHERE r.participant = (SELECT id FROM participants WHERE username = pi.participant)
+                AND network = 'braintree-cc'
+                AND error = ''
+           ) = 0;
+END;

sql/payday.sql

@@ -186,13 +186,15 @@ CREATE OR REPLACE FUNCTION process_payment_instruction() RETURNS trigger AS $$
               FROM payday_participants p
              WHERE username = NEW.participant
         );
+
         IF (NEW.amount + NEW.due <= participant.new_balance OR participant.card_hold_ok) THEN
             EXECUTE pay(NEW.participant, NEW.team, NEW.amount + NEW.due, 'to-team');
             RETURN NEW;
-        ELSE
+        ELSIF participant.has_credit_card THEN
             EXECUTE park(NEW.participant, NEW.team, NEW.amount + NEW.due);
             RETURN NULL;
         END IF;
+
         RETURN NULL;
     END;
 $$ LANGUAGE plpgsql;

tests/py/test_billing_payday.py

@@ -101,6 +101,28 @@ def test_payday_preserves_due_until_charged(self, fch):
         assert obama.balance == D('0.00')
         assert obama.get_due('TheEnterprise') == D('0.00')
 
+    @mock.patch.object(Payday, 'fetch_card_holds')
+    def test_payday_only_adds_to_dues_if_valid_cc_exists(self, fch):
+        Enterprise = self.make_team(is_approved=True)
+        self.obama.set_payment_instruction(Enterprise, '4.00')
+        assert self.obama.get_due('TheEnterprise') == D('0.00')
+
+        fch.return_value = {}
+        Payday.start().run()    # payday 0
+
+        assert self.obama.get_due('TheEnterprise') == D('4.00')
+
+        fch.return_value = {}
+        self.obama_route.update_error("failed") # card fails
+        Payday.start().run()    # payday 1
+
+        assert self.obama.get_due('TheEnterprise') == D('4.00')
+
+        fch.return_value = {}
+        Payday.start().run()    # payday 2
+
+        assert self.obama.get_due('TheEnterprise') == D('4.00')
+
     @mock.patch.object(Payday, 'fetch_card_holds')
     def test_payday_does_not_move_money_below_min_charge(self, fch):
         Enterprise  = self.make_team(is_approved=True)