CBD-1722: a fix of floating point calculations during the minimum bid…

openprocurement/auction/worker/forms.py

@@ -7,7 +7,7 @@
 from datetime import datetime
 from pytz import timezone
 import wtforms_json
-
+import decimal
 from openprocurement.auction.utils import prepare_extra_journal_fields
 
 wtforms_json.init()
@@ -34,8 +34,11 @@ def validate_bid_change_on_bidding(form, field):
             raise ValidationError(u'Too high value')
     else:
         minimal_bid = form.document['stages'][stage_id]['amount']
-        if field.data > (minimal_bid - form.document['minimalStep']['amount']):
-            raise ValidationError(u'Too high value')
+        with decimal.localcontext() as ctx:
+            ctx.prec = 2
+            max_allowed_bid = decimal.Decimal(minimal_bid) - decimal.Decimal(form.document['minimalStep']['amount'])
+            if field.data is not None and decimal.Decimal(field.data).normalize() > max_allowed_bid:
+                raise ValidationError(u'Too high value')
 
 
 def validate_bidder_id_on_bidding(form, field):

openprocurement/auction/worker/tests/unit/test_forms.py

@@ -6,8 +6,9 @@
     test_auction_document
 )
 from openprocurement.auction.worker.forms import (
-    validate_bid_value, BidsForm, form_handler
+    validate_bid_value, BidsForm, form_handler, validate_bid_change_on_bidding
 )
+from copy import deepcopy
 
 
 def test_validate_bid_value():
@@ -32,6 +33,28 @@ def test_validate_bid_value():
     validate_bid_value(None, field)
 
 
+def test_bid_change_float_precision_issue(auction):
+    """
+    checks the fix of the issue CBD-1723
+    """
+    form = BidsForm()
+    form.auction = auction
+    form.document = deepcopy(test_auction_document)
+    form.document['minimalStep']['amount'] = 72.03
+    form.document['stages'][-1]['amount'] = 14395.71
+
+    field = form.bid
+    field.data = 14323.68
+
+    try:
+        validate_bid_change_on_bidding(form, form.bid)
+    except ValidationError:
+        pytest.fail("Unexpected ValidationError: {} - {} = {}".format(
+            form.document['stages'][-1]['amount'],
+            form.document['minimalStep']['amount'],
+            field.data))
+
+
 def test_bids_form(auction, features_auction):
     form_errors = {
         'bid': [u'Bid amount is required'],