Make changes more generic

weasyprint/css/computed_values.py

@@ -176,26 +176,11 @@ def register_computer(name):
     return decorator
 
 
-def compute(element, pseudo_type, specified, computed, parent_style,
-            root_style, base_url, target_collector):
-    """Create a dict of computed values.
-
-    :param element: The HTML element these style apply to
-    :param pseudo_type: The type of pseudo-element, eg 'before', None
-    :param specified: A dict of specified values. Should contain
-                      values for all properties.
-    :param computed: A dict of already known computed values.
-                     Only contains some properties (or none).
-    :param parent_style: A dict of computed values of the parent
-                         element (should contain values for all properties),
-                         or ``None`` if ``element`` is the root element.
-    :param base_url: The base URL used to resolve relative URLs.
-    :param target_collector: A target collector used to get computed targets.
-
-    """
+def compute_variable(value, name, computed, base_url, parent_style):
     from .validation.properties import PROPERTIES
+    already_computed_value = False
 
-    def resolve_var(value, name, computed):
+    if value and isinstance(value, tuple) and value[0] == 'var()':
         variable_name, default = value[1]
         computed_value = _resolve_var(computed, variable_name, default)
         if computed_value is None:
@@ -220,11 +205,34 @@ def compute(element, pseudo_type, specified, computed, parent_style,
                 variable_name.replace('_', '-'), name.replace('_', '-'))
             if name in INHERITED and parent_style:
                 already_computed_value = True
-                return parent_style[name], already_computed_value
+                value = parent_style[name]
             else:
                 already_computed_value = name not in INITIAL_NOT_COMPUTED
-                return INITIAL_VALUES[name], already_computed_value
-        return new_value, False
+                value = INITIAL_VALUES[name]
+        elif isinstance(new_value, list):
+            value, = new_value
+        else:
+            value = new_value
+    return value, already_computed_value
+
+
+def compute(element, pseudo_type, specified, computed, parent_style,
+            root_style, base_url, target_collector):
+    """Create a dict of computed values.
+
+    :param element: The HTML element these style apply to
+    :param pseudo_type: The type of pseudo-element, eg 'before', None
+    :param specified: A dict of specified values. Should contain
+                      values for all properties.
+    :param computed: A dict of already known computed values.
+                     Only contains some properties (or none).
+    :param parent_style: A dict of computed values of the parent
+                         element (should contain values for all properties),
+                         or ``None`` if ``element`` is the root element.
+    :param base_url: The base URL used to resolve relative URLs.
+    :param target_collector: A target collector used to get computed targets.
+
+    """
 
     computer = {
         'is_root_element': parent_style is None,
@@ -249,21 +257,20 @@ def compute(element, pseudo_type, specified, computed, parent_style,
         function = getter(name)
         already_computed_value = False
 
-        if value and isinstance(value, list):
-            for i, val in enumerate(value):
-                if not isinstance(val, tuple) or val[0] != 'var()':
-                    continue
-                new_value, already_computed_value = \
-                    resolve_var(val, name, computed)
-                if name == 'content':
-                    new_value = new_value[0]
-                value[i] = new_value
-        elif value and isinstance(value, tuple) and value[0] == 'var()':
-            new_value, already_computed_value = \
-                resolve_var(value, name, computed)
-            if name == 'content':
-                new_value = new_value[0]
-            value = new_value
+        if value:
+            converted_to_list = False
+
+            if not isinstance(value, list):
+                converted_to_list = True
+                value = [value]
+
+            for i, v in enumerate(value):
+                value[i], already_computed_value = \
+                    compute_variable(v, name, computed, base_url, parent_style)
+
+            if converted_to_list:
+                value, = value
+
 
         if function is not None and not already_computed_value:
             value = function(computer, name, value)

weasyprint/css/utils.py

@@ -700,9 +700,9 @@ def get_content_list_token(token, base_url):
         return string
 
     # <var>
-    var_function = check_var_function(token)
-    if var_function is not None:
-        return var_function
+    var = check_var_function(token)
+    if var is not None:
+        return var
 
     # contents
     if get_keyword(token) == 'contents':

weasyprint/css/validation/properties.py

@@ -21,6 +21,7 @@ from ..utils import (
 PREFIX = '-weasy-'
 PROPRIETARY = set()
 UNSTABLE = set()
+MULTIVAL_PROPERTIES = set()
 
 # Yes/no validators for non-shorthand properties
 # Maps property names to functions taking a property name and a value list,
@@ -33,7 +34,7 @@ PROPERTIES = {}
 # Validators
 
 def property(property_name=None, proprietary=False, unstable=False,
-             wants_base_url=False):
+             multiple_values=False, wants_base_url=False):
     """Decorator adding a function to the ``PROPERTIES``.
 
     The name of the property covered by the decorated function is set to
@@ -69,6 +70,8 @@ def property(property_name=None, proprietary=False, unstable=False,
             PROPRIETARY.add(name)
         if unstable:
             UNSTABLE.add(name)
+        if multiple_values:
+            MULTIVAL_PROPERTIES.add(name)
         return function
     return decorator
 
@@ -89,7 +92,7 @@ def validate_non_shorthand(base_url, name, tokens, required=False):
     if not required and name not in PROPERTIES:
         raise InvalidValues('property not supported yet')
 
-    if name != 'content':
+    if name not in MULTIVAL_PROPERTIES:
         for token in tokens:
             var_function = check_var_function(token)
             if var_function:
@@ -455,7 +458,7 @@ def clip(token):
         return ()
 
 
-@property(wants_base_url=True)
+@property(multiple_values=True, wants_base_url=True)
 def content(tokens, base_url):
     """``content`` property validation."""
     # See https://www.w3.org/TR/css-content-3/#content-property

weasyprint/tests/test_boxes.py

@@ -98,7 +98,7 @@ def assert_tree(box, expected):
     assert isinstance(box, boxes.BlockBox)
     assert box.element_tag == 'body'
 
-    assert serialize(box.children) == expected
+    assert serialize(box.children) == expected, '%s != %s' % (serialize(box.children), expected,)
 
 
 def _sanity_checks(box):

weasyprint/tests/test_variables.py

@@ -11,6 +11,8 @@ import pytest
 from ..css.properties import KNOWN_PROPERTIES
 from .test_boxes import render_pages as parse
 
+SIDES = ('top', 'right', 'bottom', 'left')
+
 
 def test_variable_simple():
     page, = parse('''
@@ -83,6 +85,23 @@ def test_variable_chain():
     assert paragraph.width == 10
 
 
+def test_variable_partial_1():
+    page, = parse('''
+      <style>
+        html { --var: 10px }
+        div { margin: 0 0 0 var(--var) }
+      </style>
+      <div></div>
+    ''')
+    html, = page.children
+    body, = html.children
+    div, = body.children
+    assert div.margin_top == 0
+    assert div.margin_right == 0
+    assert div.margin_bottom == 0
+    assert div.margin_left == 10
+
+
 def test_variable_initial():
     page, = parse('''
       <style>