Add 'priority' key to CSSProperties.in

third_party/WebKit/Source/build/scripts/css_properties.py

 #!/usr/bin/env python
 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import in_generator
 import name_utilities
 
 
 class CSSProperties(in_generator.Writer):
@@ skipping 13 matching lines @@
         'setter': None,
         'initial': None,
         'type_name': None,
         'converter': None,
         'custom_all': False,
         'custom_initial': False,
         'custom_inherit': False,
         'custom_value': False,
         'builder_skip': False,
         'direction_aware': False,
+        'priority': 'Low',
         'api_class': None,
         # Generated ComputedStyle annotations.
         'field_storage_type': None,
         # Typed OM annotations.
         'typedom_types': [],
         'keywords': [],
         'initial_keyword': None,
         'keyword_only': False,
         'supports_percentage': False,
         'repeated': False,
     }
 
     valid_values = {
         'interpolable': (True, False),
         'inherited': (True, False),
         'independent': (True, False),
         'font': (True, False),
         'svg': (True, False),
         'custom_all': (True, False),
         'custom_initial': (True, False),
         'custom_inherit': (True, False),
         'custom_value': (True, False),
         'builder_skip': (True, False),
         'direction_aware': (True, False),
+        'priority': ('Animation', 'High', 'Low'),
         'keyword_only': (True, False),
     }
 
     def __init__(self, file_paths):
         in_generator.Writer.__init__(self, file_paths)
 
         properties = self.in_file.name_dictionaries
+
+        # Sort properties by priority, then alphabetically.
+        for property in properties:
+            priority_numbers = {'Animation': 0, 'High': 1, 'Low': 2}

[alancutter (OOO until 2018), 2017/01/11 04:20:56]

Add comment stating that this must match the order in CSSPropertyPriority.h (and
maybe add a TODO to auto generate that file (:).

[sashab, 2017/01/11 23:28:51]

Added comment, didn't add TODO to generate CSSPropertyPriority.h because I think
it has benefits if its handwritten. If we generate too much we can't check for
errors in our generator. :)

+            priority = priority_numbers[property['priority']]
+            name_without_leading_dash = property['name']
+            if property['name'].startswith('-'):
+                name_without_leading_dash = property['name'][1:]
+            property['sorting_key'] = (priority, name_without_leading_dash)
+
+        # Assert there are no key collisions.
+        sorting_keys = [p['sorting_key'] for p in properties]
+        assert len(sorting_keys) == len(set(sorting_keys)), \
+            ('Collision detected - two properties have the same name and priority, '
+             'a potentially non-deterministic ordering can occur.')
+        properties.sort(key=lambda p: p['sorting_key'])
+
         self._aliases = [property for property in properties if property['alias_for']]
         properties = [property for property in properties if not property['alias_for']]
 
         # 0: CSSPropertyInvalid
         # 1: CSSPropertyApplyAtRule
         # 2: CSSPropertyVariable
         self._first_enum_value = 3
 
         # StylePropertyMetadata additionally assumes there are under 1024 properties.
         assert self._first_enum_value + len(properties) < 512, 'Property aliasing expects there are under 512 properties.'
 
         for offset, property in enumerate(properties):
             property['property_id'] = name_utilities.enum_for_css_property(property['name'])
             property['upper_camel_name'] = name_utilities.camel_case(property['name'])
             property['lower_camel_name'] = name_utilities.lower_first(property['upper_camel_name'])
             property['enum_value'] = self._first_enum_value + offset
             property['is_internal'] = property['name'].startswith('-internal-')
 
         self._properties_including_aliases = properties
         self._properties = {property['property_id']: property for property in properties}
 
         # The generated code will only work with at most one alias per property
         assert len({property['alias_for'] for property in self._aliases}) == len(self._aliases)
 
         for property in self._aliases:
             property['property_id'] = name_utilities.enum_for_css_property_alias(property['name'])
             aliased_property = self._properties[name_utilities.enum_for_css_property(property['alias_for'])]
             property['enum_value'] = aliased_property['enum_value'] + 512
         self._properties_including_aliases += self._aliases