Use "Pending*" objects for all properties containing var() functions

weasyprint/css/__init__.py

@@ -23,14 +23,14 @@
 from ..logger import LOGGER, PROGRESS_LOGGER
 from ..urls import URLFetchingError, get_url_attribute, url_join
 from . import counters, media_queries
-from .computed_values import (
-    COMPUTER_FUNCTIONS, ZERO_PIXELS, compute_var, resolve_var)
+from .computed_values import COMPUTER_FUNCTIONS, ZERO_PIXELS, resolve_var
 from .properties import INHERITED, INITIAL_NOT_COMPUTED, INITIAL_VALUES
 from .utils import (
     InvalidValues, check_var_function, get_url, remove_whitespace)
 from .validation import preprocess_declarations
 from .validation.descriptors import preprocess_descriptors
 from .validation.expanders import PendingExpander
+from .validation.properties import PendingProperty
 
 # Reject anything not in here:
 PSEUDO_ELEMENTS = (
@@ -167,18 +167,6 @@ def set_computed_styles(self, element, parent, root=None, pseudo_type=None,
             element, cascaded, parent_style, pseudo_type, root_style, base_url,
             target_collector)
 
-        # The style of marker is deleted when display is different from
-        # list-item.
-        if pseudo_type is None:
-            for pseudo in (None, 'before', 'after'):
-                pseudo_style = cascaded_styles.get((element, pseudo), {})
-                if 'display' in pseudo_style:
-                    if 'list-item' in pseudo_style['display'][0]:
-                        break
-            else:
-                if (element, 'marker') in cascaded_styles:
-                    del cascaded_styles[element, 'marker']
-
     def add_page_declarations(self, page_type):
         for sheet, origin, sheet_specificity in self._sheets:
             for _rule, selector_list, declarations in sheet.page_rules:
@@ -681,27 +669,49 @@ def __missing__(self, key):
 
         if key in self.cascaded:
             # Property defined in cascaded properties.
-            keyword, computed = compute_var(key, self, parent_style)
-            value = keyword
+            value = self.cascaded[key][0]
         else:
             # Property not defined in cascaded properties, define as inherited
             # or initial value.
-            computed = False
             if key in INHERITED or key[:2] == '__':
-                keyword = 'inherit'
+                value = 'inherit'
             else:
-                keyword = 'initial'
+                value = 'initial'
 
-        if keyword == 'inherit' and parent_style is None:
+        if value == 'inherit' and parent_style is None:
             # On the root element, 'inherit' from initial values
-            keyword = 'initial'
+            value = 'initial'
 
-        if keyword == 'initial':
-            value = None if key[:2] == '__' else INITIAL_VALUES[key]
+        if isinstance(value, (PendingProperty, PendingExpander)):
+            # Property with pending values, validate them.
+            solved_tokens = []
+            for token in value.tokens:
+                if variable := check_var_function(token):
+                    variable_name, default = variable[1]
+                    tokens = resolve_var(
+                        self, variable_name, default, parent_style)
+                    solved_tokens.extend(tokens)
+                else:
+                    solved_tokens.append(token)
+            original_key = key.replace('_', '-')
+            try:
+                value = value.solve(solved_tokens, original_key)
+            except InvalidValues:
+                if key in INHERITED:
+                    # Values in parent_style are already computed.
+                    self[key] = value = parent_style[key]
+                else:
+                    value = INITIAL_VALUES[key]
+                    if key not in INITIAL_NOT_COMPUTED:
+                        # The value is the same as when computed.
+                        self[key] = value
+
+        if value == 'initial':
+            value = [] if key[:2] == '__' else INITIAL_VALUES[key]
             if key not in INITIAL_NOT_COMPUTED:
                 # The value is the same as when computed.
                 self[key] = value
-        elif keyword == 'inherit':
+        elif value == 'inherit':
             # Values in parent_style are already computed.
             self[key] = value = parent_style[key]
 
@@ -731,35 +741,7 @@ def __missing__(self, key):
             # Value already computed and saved: return.
             return self[key]
 
-        if isinstance(value, PendingExpander):
-            # Expander with pending values, validate them.
-            computed = False
-            solved_tokens = []
-            for token in value.tokens:
-                variable = check_var_function(token)
-                if variable:
-                    variable_name, default = variable[1]
-                    tokens = resolve_var(
-                        self, variable_name, default, parent_style)
-                    solved_tokens.extend(tokens)
-                else:
-                    solved_tokens.append(token)
-            original_key = key.replace('_', '-')
-            try:
-                value = value.solve(solved_tokens, original_key)
-            except InvalidValues:
-                if key in INHERITED:
-                    # Values in parent_style are already computed.
-                    self[key] = value = parent_style[key]
-                    return value
-                else:
-                    value = INITIAL_VALUES[key]
-                    if key not in INITIAL_NOT_COMPUTED:
-                        # The value is the same as when computed.
-                        self[key] = value
-                        return value
-
-        if not computed and key in COMPUTER_FUNCTIONS:
+        if key in COMPUTER_FUNCTIONS:
             # Value not computed yet: compute.
             value = COMPUTER_FUNCTIONS[key](self, key, value)
 

weasyprint/css/computed_values.py

@@ -1,7 +1,6 @@
 """Convert specified property values into computed values."""
 
 from collections import OrderedDict
-from contextlib import suppress
 from math import pi
 from urllib.parse import unquote
 
@@ -11,13 +10,10 @@
 from ..text.ffi import ffi, pango, units_to_double
 from ..text.line_break import Layout, first_line_metrics
 from ..urls import get_link_attribute
-from .properties import (
-    INHERITED, INITIAL_NOT_COMPUTED, INITIAL_VALUES, Dimension)
+from .properties import INITIAL_VALUES, Dimension
 from .utils import (
     ANGLE_TO_RADIANS, LENGTH_UNITS, LENGTHS_TO_PIXELS, check_var_function,
     safe_urljoin)
-from .validation.expanders import PendingExpander
-from .validation.properties import MULTIVAL_PROPERTIES, PROPERTIES
 
 ZERO_PIXELS = Dimension(0, 'px')
 
@@ -212,72 +208,6 @@ def decorator(function):
     return decorator
 
 
-def compute_var(name, computed_style, parent_style):
-    original_values = computed_style.cascaded[name][0]
-    validation_name = name.replace('_', '-')
-    multiple_values = validation_name in MULTIVAL_PROPERTIES
-
-    if isinstance(original_values, PendingExpander):
-        return original_values, False
-
-    if multiple_values:
-        # Property with multiple values.
-        values = list(original_values)
-    else:
-        # Property with single value, put in a list.
-        values = [original_values]
-
-    # Find variables.
-    variables = {
-        i: value[1] for i, value in enumerate(values)
-        if value and isinstance(value, tuple) and value[0] == 'var()'}
-    if not variables:
-        # No variable, return early.
-        return original_values, False
-
-    if name in INHERITED and parent_style:
-        computed = True
-        default_values = parent_style[name]
-    else:
-        computed = name not in INITIAL_NOT_COMPUTED
-        default_values = INITIAL_VALUES[name]
-
-    # Replace variables by real values.
-    validator = PROPERTIES[validation_name]
-    for i, variable in variables.items():
-        variable_name, default = variable
-        value = resolve_var(
-            computed_style, variable_name, default, parent_style)
-        if value is None:
-            LOGGER.warning(
-                'Unknown variable %r set for property %r.',
-                variable_name.replace('_', '-'), validation_name)
-            return default_values, computed
-        values[i:i+1] = value
-
-    # Validate value.
-    original_values = values
-    if validator.wants_base_url:
-        values = validator(values, computed_style.base_url)
-    else:
-        values = validator(values)
-
-    if values is None:
-        # Invalid variable value, see
-        # https://www.w3.org/TR/css-variables-1/#invalid-variables.
-        with suppress(BaseException):
-            original_values = ''.join(
-                token.serialize() for token in original_values)
-        LOGGER.warning(
-            'Unsupported computed value "%s" set in variable %r '
-            'for property %r.', original_values,
-            variable_name.replace('_', '-'), validation_name)
-        return default_values, computed
-
-    computed = False
-    return values, computed
-
-
 def compute_attr(style, values):
     # TODO: use real token parsing instead of casting with Python types
     func_name, value = values

weasyprint/css/utils.py

@@ -507,7 +507,7 @@ def check_var_function(token):
 
         # TODO: we should check authorized tokens
         # https://drafts.csswg.org/css-syntax-3/#typedef-declaration-value
-        return ('var()', (ident.value.replace('-', '_'), args or None))
+        return ('var()', (ident.value.replace('-', '_'), args))
 
 
 def get_string(token):

weasyprint/css/validation/__init__.py

@@ -166,15 +166,15 @@ def validation_error(level, reason):
             validation_error('debug', 'prefixed selectors are ignored')
             continue
 
-        expander = EXPANDERS.get(name, validate_non_shorthand)
+        validator = EXPANDERS.get(name, validate_non_shorthand)
         tokens = remove_whitespace(declaration.value)
         try:
             # Having no tokens is allowed by grammar but refused by all
             # properties and expanders.
             if not tokens:
                 raise InvalidValues('no value')
             # Use list() to consume generators now and catch any error.
-            result = list(expander(tokens, name, base_url))
+            result = list(validator(tokens, name, base_url))
         except InvalidValues as exc:
             validation_error(
                 'warning',

weasyprint/css/validation/expanders.py

@@ -26,30 +26,27 @@
 class PendingExpander:
     """Expander with validation done when defining calculated values."""
     # See https://drafts.csswg.org/css-variables-2/#variables-in-shorthands.
-    def __init__(self, tokens, expander):
+    def __init__(self, tokens, validator):
         self.tokens = tokens
-        self.expander = expander
+        self.validator = validator
         self._reported_error = False
 
     def solve(self, tokens, wanted_key):
         """Get validated value for wanted key."""
         try:
-            for key, value in self.expander(tokens):
+            for key, value in self.validator(tokens):
                 if key.startswith('-'):
-                    key = f'{self.expander.keywords["name"]}{key}'
+                    key = f'{self.validator.keywords["name"]}{key}'
                 if key == wanted_key:
                     return value
         except InvalidValues as exc:
             if self._reported_error:
                 raise exc
-            source_line = tokens[0].source_line
-            source_column = tokens[0].source_column
-            prop = self.expander.keywords["name"]
+            prop = self.validator.keywords['name']
+            source_line = self.tokens[0].source_line
+            source_column = self.tokens[0].source_column
             value = ' '.join(token.serialize() for token in tokens)
-            if exc.args and exc.args[0]:
-                message = exc.args[0]
-            else:
-                message = 'invalid value'
+            message = (exc.args and exc.args[0]) or 'invalid value'
             LOGGER.warning(
                 'Ignored `%s: %s` at %d:%d, %s.',
                 prop, value, source_line, source_column, message)