parsers: raise ValueError for invalid TimePoints

.bandit

@@ -0,0 +1 @@
+skips: ['B101']

.travis.yml

@@ -8,8 +8,7 @@ python:
   - 2.6
   - 2.7
 env:
-  - RUN_COVERAGE=false
-  - RUN_COVERAGE=true
+  - TZ=UTC
 
 matrix:
   fast_finish: true

isodatetime/data.py

@@ -1425,8 +1425,20 @@ def add_months(self, num_months):
         if was_week_date:
             self.to_week_date()
 
-    def tick_over(self):
-        """Correct all the units going from smallest to largest."""
+    def tick_over(self, check_changes=False):
+        """Correct all the units going from smallest to largest.
+
+        Args:
+            check_changes (bool, optional):
+                If True tick_over will return a dict of any changed fields.
+
+        Returns:
+            dict: Dictionary of changed fields with before and after values
+            if check_changes is True else None.
+
+        """
+        if check_changes:
+            before = {key: getattr(self, key) for key in self.DATA_ATTRIBUTES}
         if (self.hour_of_day is not None and
                 self.minute_of_hour is not None):
             hours_remainder = self.hour_of_day - int(self.hour_of_day)
@@ -1491,6 +1503,12 @@ def tick_over(self):
             while self.month_of_year > CALENDAR.MONTHS_IN_YEAR:
                 self.month_of_year -= CALENDAR.MONTHS_IN_YEAR
                 self.year += 1
+        if check_changes:
+            return {
+                key: (value, getattr(self, key))
+                for key, value in before.items()
+                if getattr(self, key) != value
+            }
 
     def _tick_over_day_of_month(self):
         if self.day_of_month < 1:

isodatetime/parsers.py

@@ -232,15 +232,44 @@ def parse_time_zone_expression_to_regex(expression):
         expression = "^" + expression + "$"
         return expression
 
-    def parse(self, timepoint_string, dump_format=None, dump_as_parsed=False):
-        """Parse a user-supplied timepoint string."""
+    def parse(self, timepoint_string, dump_format=None, dump_as_parsed=False,
+              validate=True):
+        """Parse a user-supplied timepoint string.
+
+        Args:
+            validate (bool, optional):
+                If True the datetime will be "ticked over", if this results in
+                a change a ValueError will be raised.
+                Note that `validate` is incompatible with `allow_truncated`.
+
+        Raises:
+            ValueError: If validation fails.
+
+        Returns:
+            TimePoint
+
+        """
         date_info, time_info, parsed_expr = self.get_info(timepoint_string)
         if dump_as_parsed:
             dump_format = parsed_expr
-        return self._create_timepoint_from_info(
+        time_point = self._create_timepoint_from_info(
             date_info, time_info, dump_format=dump_format,
             truncated_dump_format=dump_format)
 
+        if validate and not self.allow_truncated:
+            changed_fields = time_point.tick_over(check_changes=True)
+            if changed_fields:
+                raise ValueError(
+                    'Invalid date-time components: ' +
+                    ', '.join((
+                        '%s=%s' % (key, before)
+                        for key, (before, after) in changed_fields.items()
+                        if before > after
+                    ))
+                )
+
+        return time_point
+
     def _create_timepoint_from_info(self, date_info, time_info,
                                     dump_format=None,
                                     truncated_dump_format=None):
@@ -574,7 +603,11 @@ def parse(self, expression):
             # TimePoint-like duration - don't allow our negative extension.
             try:
                 timepoint = parse_timepoint_expression(
-                    expression[1:], allow_truncated=False,
+                    expression[1:],
+                    # this is a duration but we are parsing it as a timepoint
+                    # so don't validate.
+                    validate=False,
+                    allow_truncated=False,
                     assumed_time_zone=(0, 0)
                 )
             except ISO8601SyntaxError:
@@ -597,7 +630,7 @@ def parse(self, expression):
         raise ISO8601SyntaxError("duration", expression)
 
 
-def parse_timepoint_expression(timepoint_expression, **kwargs):
+def parse_timepoint_expression(timepoint_expression, validate=True, **kwargs):
     """Return a data model that represents timepoint_expression."""
     parser = TimePointParser(**kwargs)
-    return parser.parse(timepoint_expression)
+    return parser.parse(timepoint_expression, validate=validate)

isodatetime/tests/test_parser.py

@@ -0,0 +1,42 @@
+# -*- coding: utf-8 -*-
+# ----------------------------------------------------------------------------
+# Copyright (C) 2013-2019 British Crown (Met Office) & Contributors.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+# ----------------------------------------------------------------------------
+"""Test isodatetime.parsers."""
+
+import pytest
+
+from isodatetime.parsers import TimePointParser
+
+
+def test_invalid_components():
+    parser = TimePointParser()
+    for date, invalid in {
+        '2000-01-01T00:00:60': ['second_of_minute=60'],
+        '2000-01-01T00:60:00': ['minute_of_hour=60'],
+        '2000-01-01T60:00:00': ['hour_of_day=60'],
+        '2000-01-32T00:00:00': ['day_of_month=32'],
+        '2000-13-00T00:00:00': ['month_of_year=13'],
+        '2000-13-32T60:60:60': ['month_of_year=13',
+                                'day_of_month=32',
+                                'hour_of_day=60',
+                                'minute_of_hour=60',
+                                'second_of_minute=60']
+    }.items():
+        with pytest.raises(ValueError) as exc:
+            parser.parse(date)
+        for item in invalid:
+            assert item in str(exc)