1580 lines
58 KiB
Python
1580 lines
58 KiB
Python
"""
|
||
weasyprint.formatting_structure.build
|
||
-------------------------------------
|
||
|
||
Turn an element tree with associated CSS style (computed values)
|
||
into a "before layout" formatting structure / box tree.
|
||
|
||
This includes creating anonymous boxes and processing whitespace
|
||
as necessary.
|
||
|
||
:copyright: Copyright 2011-2019 Simon Sapin and contributors, see AUTHORS.
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||
:license: BSD, see LICENSE for details.
|
||
|
||
"""
|
||
|
||
import copy
|
||
import re
|
||
import unicodedata
|
||
|
||
import tinycss2.color3
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||
|
||
from .. import html
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from ..css import computed_values, properties
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||
from ..logger import LOGGER
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||
from . import boxes, counters
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||
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||
# Maps values of the ``display`` CSS property to box types.
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||
BOX_TYPE_FROM_DISPLAY = {
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||
'block': boxes.BlockBox,
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||
'list-item': boxes.BlockBox,
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||
'inline': boxes.InlineBox,
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||
'inline-block': boxes.InlineBlockBox,
|
||
'table': boxes.TableBox,
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||
'inline-table': boxes.InlineTableBox,
|
||
'table-row': boxes.TableRowBox,
|
||
'table-row-group': boxes.TableRowGroupBox,
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||
'table-header-group': boxes.TableRowGroupBox,
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||
'table-footer-group': boxes.TableRowGroupBox,
|
||
'table-column': boxes.TableColumnBox,
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||
'table-column-group': boxes.TableColumnGroupBox,
|
||
'table-cell': boxes.TableCellBox,
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||
'table-caption': boxes.TableCaptionBox,
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||
'flex': boxes.FlexBox,
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||
'inline-flex': boxes.InlineFlexBox,
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||
}
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||
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||
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||
def build_formatting_structure(element_tree, style_for, get_image_from_uri,
|
||
base_url, target_collector):
|
||
"""Build a formatting structure (box tree) from an element tree."""
|
||
box_list = element_to_box(
|
||
element_tree, style_for, get_image_from_uri, base_url,
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||
target_collector)
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||
if box_list:
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||
box, = box_list
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||
else:
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||
# No root element
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||
def root_style_for(element, pseudo_type=None):
|
||
style = style_for(element, pseudo_type)
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||
if style:
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||
if element == element_tree:
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||
style['display'] = 'block'
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else:
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||
style['display'] = 'none'
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||
return style
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||
box, = element_to_box(
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||
element_tree, root_style_for, get_image_from_uri, base_url,
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||
target_collector)
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||
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||
target_collector.check_pending_targets()
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||
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||
box.is_for_root_element = True
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||
# If this is changed, maybe update weasy.layout.pages.make_margin_boxes()
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process_whitespace(box)
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box = anonymous_table_boxes(box)
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box = flex_boxes(box)
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box = inline_in_block(box)
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box = block_in_inline(box)
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box = set_viewport_overflow(box)
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return box
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||
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||
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def make_box(element_tag, style, content, element):
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box = BOX_TYPE_FROM_DISPLAY[style['display']](
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element_tag, style, element, content)
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||
return box
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||
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||
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def element_to_box(element, style_for, get_image_from_uri, base_url,
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||
target_collector, state=None):
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"""Convert an element and its children into a box with children.
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||
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Return a list of boxes. Most of the time the list will have one item but
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may have zero or more than one.
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||
Eg.::
|
||
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<p>Some <em>emphasised</em> text.</p>
|
||
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||
gives (not actual syntax)::
|
||
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BlockBox[
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||
TextBox['Some '],
|
||
InlineBox[
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||
TextBox['emphasised'],
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||
],
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||
TextBox[' text.'],
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||
]
|
||
|
||
``TextBox``es are anonymous inline boxes:
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||
See http://www.w3.org/TR/CSS21/visuren.html#anonymous
|
||
|
||
"""
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||
if not isinstance(element.tag, str):
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||
# We ignore comments and XML processing instructions.
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||
return []
|
||
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||
style = style_for(element)
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||
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||
# TODO: should be the used value. When does the used value for `display`
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||
# differ from the computer value?
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||
display = style['display']
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||
if display == 'none':
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||
return []
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||
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||
box = make_box(element.tag, style, [], element)
|
||
|
||
if state is None:
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||
# use a list to have a shared mutable object
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||
state = (
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||
# Shared mutable objects:
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[0], # quote_depth: single integer
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{}, # counter_values: name -> stacked/scoped values
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||
[set()] # counter_scopes: element tree depths -> counter names
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||
)
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||
_quote_depth, counter_values, counter_scopes = state
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||
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update_counters(state, style)
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||
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children = []
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||
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# If this element’s direct children create new scopes, the counter
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# names will be in this new list
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||
counter_scopes.append(set())
|
||
|
||
box.first_letter_style = style_for(element, 'first-letter')
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||
box.first_line_style = style_for(element, 'first-line')
|
||
|
||
marker_boxes = []
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||
if style['display'] == 'list-item':
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||
marker_boxes = list(marker_to_box(
|
||
element, state, style, style_for, get_image_from_uri,
|
||
target_collector))
|
||
children.extend(marker_boxes)
|
||
|
||
children.extend(before_after_to_box(
|
||
element, 'before', state, style_for, get_image_from_uri,
|
||
target_collector))
|
||
|
||
# collect anchor's counter_values, maybe it's a target.
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||
# to get the spec-conform counter_values we must do it here,
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||
# after the ::before is parsed and before the ::after is
|
||
if style['anchor']:
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||
target_collector.store_target(style['anchor'], counter_values, box)
|
||
|
||
text = element.text
|
||
if text:
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||
children.append(boxes.TextBox.anonymous_from(box, text))
|
||
|
||
for child_element in element:
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||
children.extend(element_to_box(
|
||
child_element, style_for, get_image_from_uri, base_url,
|
||
target_collector, state))
|
||
text = child_element.tail
|
||
if text:
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||
text_box = boxes.TextBox.anonymous_from(box, text)
|
||
if children and isinstance(children[-1], boxes.TextBox):
|
||
children[-1].text += text_box.text
|
||
else:
|
||
children.append(text_box)
|
||
children.extend(before_after_to_box(
|
||
element, 'after', state, style_for, get_image_from_uri,
|
||
target_collector))
|
||
|
||
# Scopes created by this element’s children stop here.
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||
for name in counter_scopes.pop():
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||
counter_values[name].pop()
|
||
if not counter_values[name]:
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||
counter_values.pop(name)
|
||
|
||
box.children = children
|
||
# calculate string-set and bookmark-label
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set_content_lists(element, box, style, counter_values, target_collector)
|
||
|
||
if marker_boxes and len(box.children) == 1:
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||
# See https://www.w3.org/TR/css-lists-3/#list-style-position-outside
|
||
#
|
||
# "The size or contents of the marker box may affect the height of the
|
||
# principal block box and/or the height of its first line box, and in
|
||
# some cases may cause the creation of a new line box; this
|
||
# interaction is also not defined."
|
||
#
|
||
# We decide here to add a zero-width space to have a minimum
|
||
# height. Adding text boxes is not the best idea, but it's not a good
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# moment to add an empty line box, and the specification lets us do
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||
# almost what we want, so…
|
||
if style['list_style_position'] == 'outside':
|
||
box.children.append(boxes.TextBox.anonymous_from(box, ''))
|
||
|
||
# Specific handling for the element. (eg. replaced element)
|
||
return html.handle_element(element, box, get_image_from_uri, base_url)
|
||
|
||
|
||
def before_after_to_box(element, pseudo_type, state, style_for,
|
||
get_image_from_uri, target_collector):
|
||
"""Return the boxes for ::before or ::after pseudo-element."""
|
||
style = style_for(element, pseudo_type)
|
||
if pseudo_type and style is None:
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||
# Pseudo-elements with no style at all do not get a style dict.
|
||
# Their initial content property computes to 'none'.
|
||
return []
|
||
|
||
# TODO: should be the computed value. When does the used value for
|
||
# `display` differ from the computer value? It's at least wrong for
|
||
# `content` where 'normal' computes as 'inhibit' for pseudo elements.
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||
display = style['display']
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||
content = style['content']
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||
if 'none' in (display, content) or content in ('normal', 'inhibit'):
|
||
return []
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||
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||
box = make_box('%s::%s' % (element.tag, pseudo_type), style, [], element)
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||
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||
quote_depth, counter_values, _counter_scopes = state
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update_counters(state, style)
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||
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||
children = []
|
||
|
||
if display == 'list-item':
|
||
marker_boxes = list(marker_to_box(
|
||
element, state, style, style_for, get_image_from_uri,
|
||
target_collector))
|
||
children.extend(marker_boxes)
|
||
|
||
children.extend(content_to_boxes(
|
||
style, box, quote_depth, counter_values, get_image_from_uri,
|
||
target_collector))
|
||
|
||
box.children = children
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||
return [box]
|
||
|
||
|
||
def marker_to_box(element, state, parent_style, style_for, get_image_from_uri,
|
||
target_collector):
|
||
"""Yield the box for ::marker pseudo-element if there is one.
|
||
|
||
https://drafts.csswg.org/css-lists-3/#marker-pseudo
|
||
|
||
"""
|
||
style = style_for(element, 'marker')
|
||
|
||
children = []
|
||
|
||
# TODO: should be the computed value. When does the used value for
|
||
# `display` differ from the computer value? It's at least wrong for
|
||
# `content` where 'normal' computes as 'inhibit' for pseudo elements.
|
||
quote_depth, counter_values, _counter_scopes = state
|
||
|
||
box = make_box('%s::marker' % element.tag, style, children, element)
|
||
|
||
if style['display'] == 'none':
|
||
return
|
||
|
||
image_type, image = style['list_style_image']
|
||
|
||
if style['content'] not in ('normal', 'inhibit'):
|
||
children.extend(content_to_boxes(
|
||
style, box, quote_depth, counter_values, get_image_from_uri,
|
||
target_collector))
|
||
|
||
else:
|
||
if image_type == 'url':
|
||
# image may be None here too, in case the image is not available.
|
||
image = get_image_from_uri(image)
|
||
if image is not None:
|
||
box = boxes.InlineReplacedBox.anonymous_from(box, image)
|
||
children.append(box)
|
||
|
||
if not children and style['list_style_type'] != 'none':
|
||
counter_value = counter_values.get('list-item', [0])[-1]
|
||
# TODO: rtl numbered list has the dot on the left
|
||
marker_text = counters.format_list_marker(
|
||
counter_value, style['list_style_type'])
|
||
box = boxes.TextBox.anonymous_from(box, marker_text)
|
||
box.style['white_space'] = 'pre-wrap'
|
||
children.append(box)
|
||
|
||
if not children:
|
||
return
|
||
|
||
if parent_style['list_style_position'] == 'outside':
|
||
marker_box = boxes.BlockBox.anonymous_from(box, children)
|
||
# We can safely edit everything that can't be changed by user style
|
||
# See https://drafts.csswg.org/css-pseudo-4/#marker-pseudo
|
||
marker_box.style['position'] = 'absolute'
|
||
if parent_style['direction'] == 'ltr':
|
||
translate_x = properties.Dimension(-100, '%')
|
||
else:
|
||
translate_x = properties.Dimension(100, '%')
|
||
translate_y = computed_values.ZERO_PIXELS
|
||
marker_box.style['transform'] = (
|
||
('translate', (translate_x, translate_y)),)
|
||
else:
|
||
marker_box = boxes.InlineBox.anonymous_from(box, children)
|
||
yield marker_box
|
||
|
||
|
||
def _collect_missing_counter(counter_name, counter_values, missing_counters):
|
||
"""Collect missing counters."""
|
||
if counter_name not in list(counter_values) + missing_counters:
|
||
missing_counters.append(counter_name)
|
||
|
||
|
||
def _collect_missing_target_counter(counter_name, lookup_counter_values,
|
||
anchor_name, missing_target_counters):
|
||
"""Collect missing target counters.
|
||
|
||
The corresponding TargetLookupItem caches the target's page based
|
||
counter values during pagination.
|
||
|
||
"""
|
||
if counter_name not in lookup_counter_values:
|
||
missing_counters = missing_target_counters.setdefault(anchor_name, [])
|
||
if counter_name not in missing_counters:
|
||
missing_counters.append(counter_name)
|
||
|
||
|
||
def compute_content_list(content_list, parent_box, counter_values, css_token,
|
||
parse_again, target_collector,
|
||
get_image_from_uri=None, quote_depth=None,
|
||
quote_style=None, context=None, page=None,
|
||
element=None):
|
||
"""Compute and return the boxes corresponding to the ``content_list``.
|
||
|
||
``parse_again`` is called to compute the ``content_list`` again when
|
||
``target_collector.lookup_target()`` detected a pending target.
|
||
|
||
``build_formatting_structure`` calls
|
||
``target_collector.check_pending_targets()`` after the first pass to do
|
||
required reparsing.
|
||
|
||
"""
|
||
# TODO: Some computation done here may be done in computed_values
|
||
# instead. We currently miss at least style_for, counters and quotes
|
||
# context in computer. Some work will still need to be done here though,
|
||
# like box creation for URIs.
|
||
boxlist = []
|
||
texts = []
|
||
|
||
missing_counters = []
|
||
missing_target_counters = {}
|
||
in_page_context = context is not None and page is not None
|
||
|
||
# Collect missing counters during build_formatting_structure.
|
||
# Pointless to collect missing target counters in MarginBoxes.
|
||
need_collect_missing = target_collector.collecting and not in_page_context
|
||
|
||
# TODO: remove attribute or set a default value in Box class
|
||
if not hasattr(parent_box, 'cached_counter_values'):
|
||
# Store the counter_values in the parent_box to make them accessible
|
||
# in @page context. Obsoletes the parse_again function's deepcopy.
|
||
# TODO: Is propbably superfluous in_page_context.
|
||
parent_box.cached_counter_values = copy.deepcopy(counter_values)
|
||
|
||
for type_, value in content_list:
|
||
if type_ == 'string':
|
||
texts.append(value)
|
||
elif type_ == 'url' and get_image_from_uri is not None:
|
||
origin, uri = value
|
||
if origin != 'external':
|
||
# Embedding internal references is impossible
|
||
continue
|
||
image = get_image_from_uri(uri)
|
||
if image is not None:
|
||
text = ''.join(texts)
|
||
if text:
|
||
boxlist.append(
|
||
boxes.TextBox.anonymous_from(parent_box, text))
|
||
texts = []
|
||
boxlist.append(
|
||
boxes.InlineReplacedBox.anonymous_from(parent_box, image))
|
||
elif type_ == 'content()':
|
||
added_text = TEXT_CONTENT_EXTRACTORS[value](parent_box)
|
||
# Simulate the step of white space processing
|
||
# (normally done during the layout)
|
||
added_text = added_text.strip()
|
||
texts.append(added_text)
|
||
elif type_ == 'counter()':
|
||
counter_name, counter_style = value
|
||
if need_collect_missing:
|
||
_collect_missing_counter(
|
||
counter_name, counter_values, missing_counters)
|
||
counter_value = counter_values.get(counter_name, [0])[-1]
|
||
texts.append(counters.format(counter_value, counter_style))
|
||
elif type_ == 'counters()':
|
||
counter_name, separator, counter_style = value
|
||
if need_collect_missing:
|
||
_collect_missing_counter(
|
||
counter_name, counter_values, missing_counters)
|
||
texts.append(separator.join(
|
||
counters.format(counter_value, counter_style)
|
||
for counter_value in counter_values.get(counter_name, [0])))
|
||
elif type_ == 'string()':
|
||
if not in_page_context:
|
||
# string() is currently only valid in @page context
|
||
# See https://github.com/Kozea/WeasyPrint/issues/723
|
||
LOGGER.warning(
|
||
'"string(%s)" is only allowed in page margins' %
|
||
(' '.join(value)))
|
||
continue
|
||
texts.append(context.get_string_set_for(page, *value) or '')
|
||
elif type_ == 'target-counter()':
|
||
anchor_token, counter_name, counter_style = value
|
||
lookup_target = target_collector.lookup_target(
|
||
anchor_token, parent_box, css_token, parse_again)
|
||
if lookup_target.state == 'up-to-date':
|
||
target_values = lookup_target.target_box.cached_counter_values
|
||
if need_collect_missing:
|
||
_collect_missing_target_counter(
|
||
counter_name, target_values,
|
||
target_collector.anchor_name_from_token(anchor_token),
|
||
missing_target_counters)
|
||
# Mixin target's cached page counters.
|
||
# cached_page_counter_values are empty during layout.
|
||
local_counters = (
|
||
lookup_target.cached_page_counter_values.copy())
|
||
local_counters.update(target_values)
|
||
counter_value = local_counters.get(counter_name, [0])[-1]
|
||
texts.append(counters.format(counter_value, counter_style))
|
||
else:
|
||
texts = []
|
||
break
|
||
elif type_ == 'target-counters()':
|
||
anchor_token, counter_name, separator, counter_style = value
|
||
lookup_target = target_collector.lookup_target(
|
||
anchor_token, parent_box, css_token, parse_again)
|
||
if lookup_target.state == 'up-to-date':
|
||
if separator[0] != 'string':
|
||
break
|
||
separator_string = separator[1]
|
||
target_values = lookup_target.target_box.cached_counter_values
|
||
if need_collect_missing:
|
||
_collect_missing_target_counter(
|
||
counter_name, target_values,
|
||
target_collector.anchor_name_from_token(anchor_token),
|
||
missing_target_counters)
|
||
# Mixin target's cached page counters.
|
||
# cached_page_counter_values are empty during layout.
|
||
local_counters = (
|
||
lookup_target.cached_page_counter_values.copy())
|
||
local_counters.update(target_values)
|
||
texts.append(separator_string.join(
|
||
counters.format(counter_value, counter_style)
|
||
for counter_value in local_counters.get(
|
||
counter_name, [0])))
|
||
else:
|
||
texts = []
|
||
break
|
||
elif type_ == 'target-text()':
|
||
anchor_token, text_style = value
|
||
lookup_target = target_collector.lookup_target(
|
||
anchor_token, parent_box, css_token, parse_again)
|
||
if lookup_target.state == 'up-to-date':
|
||
target_box = lookup_target.target_box
|
||
# TODO: 'before'- and 'after'- content referring missing
|
||
# counters are not properly set.
|
||
text = TEXT_CONTENT_EXTRACTORS[text_style](target_box)
|
||
# Simulate the step of white space processing
|
||
# (normally done during the layout)
|
||
texts.append(text.strip())
|
||
else:
|
||
texts = []
|
||
break
|
||
elif (type_ == 'quote' and
|
||
quote_depth is not None and
|
||
quote_style is not None):
|
||
is_open = 'open' in value
|
||
insert = not value.startswith('no-')
|
||
if not is_open:
|
||
quote_depth[0] = max(0, quote_depth[0] - 1)
|
||
if insert:
|
||
open_quotes, close_quotes = quote_style
|
||
quotes = open_quotes if is_open else close_quotes
|
||
texts.append(quotes[min(quote_depth[0], len(quotes) - 1)])
|
||
if is_open:
|
||
quote_depth[0] += 1
|
||
elif type_ == 'element()':
|
||
if not in_page_context:
|
||
LOGGER.warning(
|
||
'"element(%s)" is only allowed in page margins' %
|
||
(' '.join(value)))
|
||
continue
|
||
new_box = context.get_running_element_for(page, *value)
|
||
if new_box is None:
|
||
continue
|
||
new_box = new_box.deepcopy()
|
||
new_box.style['position'] = 'static'
|
||
for child in new_box.descendants():
|
||
if child.style['content'] in ('normal', 'none'):
|
||
continue
|
||
child.children = content_to_boxes(
|
||
child.style, child, quote_depth, counter_values,
|
||
get_image_from_uri, target_collector, context=context,
|
||
page=page)
|
||
boxlist.append(new_box)
|
||
text = ''.join(texts)
|
||
if text:
|
||
boxlist.append(boxes.TextBox.anonymous_from(parent_box, text))
|
||
# Only add CounterLookupItem if the content_list actually produced text
|
||
target_collector.collect_missing_counters(
|
||
parent_box, css_token, parse_again, missing_counters,
|
||
missing_target_counters)
|
||
|
||
return boxlist if (texts or boxlist) else None
|
||
|
||
|
||
def content_to_boxes(style, parent_box, quote_depth, counter_values,
|
||
get_image_from_uri, target_collector, context=None,
|
||
page=None):
|
||
"""Take the value of a ``content`` property and return boxes."""
|
||
def parse_again(mixin_pagebased_counters=None):
|
||
"""Closure to parse the ``parent_boxes`` children all again."""
|
||
|
||
# Neither alters the mixed-in nor the cached counter values, no
|
||
# need to deepcopy here
|
||
if mixin_pagebased_counters is None:
|
||
local_counters = {}
|
||
else:
|
||
local_counters = mixin_pagebased_counters.copy()
|
||
local_counters.update(parent_box.cached_counter_values)
|
||
|
||
local_children = []
|
||
local_children.extend(content_to_boxes(
|
||
style, parent_box, orig_quote_depth, local_counters,
|
||
get_image_from_uri, target_collector))
|
||
|
||
# TODO: do we need to add markers here?
|
||
# TODO: redo the formatting structure of the parent instead of hacking
|
||
# the already formatted structure. Find why inline_in_blocks has
|
||
# sometimes already been called, and sometimes not.
|
||
if (len(parent_box.children) == 1 and
|
||
isinstance(parent_box.children[0], boxes.LineBox)):
|
||
parent_box.children[0].children = local_children
|
||
else:
|
||
parent_box.children = local_children
|
||
|
||
if style['content'] == 'inhibit':
|
||
return []
|
||
|
||
orig_quote_depth = quote_depth[:]
|
||
css_token = 'content'
|
||
box_list = compute_content_list(
|
||
style['content'], parent_box, counter_values, css_token, parse_again,
|
||
target_collector, get_image_from_uri, quote_depth, style['quotes'],
|
||
context, page)
|
||
return box_list or []
|
||
|
||
|
||
def compute_string_set(element, box, string_name, content_list,
|
||
counter_values, target_collector):
|
||
"""Parse the content-list value of ``string_name`` for ``string-set``."""
|
||
def parse_again(mixin_pagebased_counters=None):
|
||
"""Closure to parse the string-set string value all again."""
|
||
|
||
# Neither alters the mixed-in nor the cached counter values, no
|
||
# need to deepcopy here
|
||
if mixin_pagebased_counters is None:
|
||
local_counters = {}
|
||
else:
|
||
local_counters = mixin_pagebased_counters.copy()
|
||
local_counters.update(box.cached_counter_values)
|
||
|
||
compute_string_set(
|
||
element, box, string_name, content_list, local_counters,
|
||
target_collector)
|
||
|
||
css_token = 'string-set::%s' % string_name
|
||
box_list = compute_content_list(
|
||
content_list, box, counter_values, css_token, parse_again,
|
||
target_collector, element=element)
|
||
if box_list is not None:
|
||
string = ''.join(
|
||
box.text for box in box_list if isinstance(box, boxes.TextBox))
|
||
# Avoid duplicates, care for parse_again and missing counters, don't
|
||
# change the pointer
|
||
for string_set_tuple in box.string_set:
|
||
if string_set_tuple[0] == string_name:
|
||
box.string_set.remove(string_set_tuple)
|
||
break
|
||
box.string_set.append((string_name, string))
|
||
|
||
|
||
def compute_bookmark_label(element, box, content_list, counter_values,
|
||
target_collector):
|
||
"""Parses the content-list value for ``bookmark-label``."""
|
||
def parse_again(mixin_pagebased_counters={}):
|
||
"""Closure to parse the bookmark-label all again."""
|
||
# Neither alters the mixed-in nor the cached counter values, no
|
||
# need to deepcopy here
|
||
if mixin_pagebased_counters is None:
|
||
local_counters = {}
|
||
else:
|
||
local_counters = mixin_pagebased_counters.copy()
|
||
local_counters = mixin_pagebased_counters.copy()
|
||
local_counters.update(box.cached_counter_values)
|
||
compute_bookmark_label(
|
||
element, box, content_list, local_counters, target_collector)
|
||
|
||
css_token = 'bookmark-label'
|
||
box_list = compute_content_list(
|
||
content_list, box, counter_values, css_token, parse_again,
|
||
target_collector, element=element)
|
||
|
||
if box_list is None:
|
||
box.bookmark_label = ''
|
||
else:
|
||
box.bookmark_label = ''.join(
|
||
box.text for box in box_list if isinstance(box, boxes.TextBox))
|
||
|
||
|
||
def set_content_lists(element, box, style, counter_values, target_collector):
|
||
"""Set the content-lists values.
|
||
|
||
These content-lists are used in GCPM properties like ``string-set`` and
|
||
``bookmark-label``.
|
||
|
||
"""
|
||
box.string_set = []
|
||
if style['string_set'] != 'none':
|
||
for i, (string_name, string_values) in enumerate(style['string_set']):
|
||
compute_string_set(
|
||
element, box, string_name, string_values, counter_values,
|
||
target_collector)
|
||
if style['bookmark_label'] == 'none':
|
||
box.bookmark_label = ''
|
||
else:
|
||
compute_bookmark_label(
|
||
element, box, style['bookmark_label'], counter_values,
|
||
target_collector)
|
||
|
||
|
||
def update_counters(state, style):
|
||
"""Handle the ``counter-*`` properties."""
|
||
_quote_depth, counter_values, counter_scopes = state
|
||
sibling_scopes = counter_scopes[-1]
|
||
|
||
for name, value in style['counter_reset']:
|
||
if name in sibling_scopes:
|
||
counter_values[name].pop()
|
||
else:
|
||
sibling_scopes.add(name)
|
||
counter_values.setdefault(name, []).append(value)
|
||
|
||
# XXX Disabled for now, only exists in Lists3’s editor’s draft.
|
||
# for name, value in style['counter_set']:
|
||
# values = counter_values.setdefault(name, [])
|
||
# if not values:
|
||
# assert name not in sibling_scopes
|
||
# sibling_scopes.add(name)
|
||
# values.append(0)
|
||
# values[-1] = value
|
||
|
||
counter_increment = style['counter_increment']
|
||
if counter_increment == 'auto':
|
||
# 'auto' is the initial value but is not valid in stylesheet:
|
||
# there was no counter-increment declaration for this element.
|
||
# (Or the winning value was 'initial'.)
|
||
# http://dev.w3.org/csswg/css3-lists/#declaring-a-list-item
|
||
if style['display'] == 'list-item':
|
||
counter_increment = [('list-item', 1)]
|
||
else:
|
||
counter_increment = []
|
||
for name, value in counter_increment:
|
||
values = counter_values.setdefault(name, [])
|
||
if not values:
|
||
assert name not in sibling_scopes
|
||
sibling_scopes.add(name)
|
||
values.append(0)
|
||
values[-1] += value
|
||
|
||
|
||
def is_whitespace(box, _has_non_whitespace=re.compile('\\S').search):
|
||
"""Return True if ``box`` is a TextBox with only whitespace."""
|
||
return isinstance(box, boxes.TextBox) and not _has_non_whitespace(box.text)
|
||
|
||
|
||
def wrap_improper(box, children, wrapper_type, test=None):
|
||
"""
|
||
Wrap consecutive children that do not pass ``test`` in a box of type
|
||
``wrapper_type``.
|
||
|
||
``test`` defaults to children being of the same type as ``wrapper_type``.
|
||
|
||
"""
|
||
if test is None:
|
||
def test(child):
|
||
return isinstance(child, wrapper_type)
|
||
improper = []
|
||
for child in children:
|
||
if test(child):
|
||
if improper:
|
||
wrapper = wrapper_type.anonymous_from(box, children=[])
|
||
# Apply the rules again on the new wrapper
|
||
yield table_boxes_children(wrapper, improper)
|
||
improper = []
|
||
yield child
|
||
else:
|
||
# Whitespace either fail the test or were removed earlier,
|
||
# so there is no need to take special care with the definition
|
||
# of "consecutive".
|
||
if isinstance(box, boxes.FlexContainerBox):
|
||
# The display value of a flex item must be "blockified", see
|
||
# https://www.w3.org/TR/css-flexbox-1/#flex-items
|
||
# TODO: These blocks are currently ignored, we should
|
||
# "blockify" them and their children.
|
||
pass
|
||
else:
|
||
improper.append(child)
|
||
if improper:
|
||
wrapper = wrapper_type.anonymous_from(box, children=[])
|
||
# Apply the rules again on the new wrapper
|
||
yield table_boxes_children(wrapper, improper)
|
||
|
||
|
||
def anonymous_table_boxes(box):
|
||
"""Remove and add boxes according to the table model.
|
||
|
||
Take and return a ``Box`` object.
|
||
|
||
See http://www.w3.org/TR/CSS21/tables.html#anonymous-boxes
|
||
|
||
"""
|
||
if not isinstance(box, boxes.ParentBox) or box.is_running():
|
||
return box
|
||
|
||
# Do recursion.
|
||
children = [anonymous_table_boxes(child) for child in box.children]
|
||
return table_boxes_children(box, children)
|
||
|
||
|
||
def table_boxes_children(box, children):
|
||
"""Internal implementation of anonymous_table_boxes()."""
|
||
if isinstance(box, boxes.TableColumnBox): # rule 1.1
|
||
# Remove all children.
|
||
children = []
|
||
elif isinstance(box, boxes.TableColumnGroupBox): # rule 1.2
|
||
# Remove children other than table-column.
|
||
children = [
|
||
child for child in children
|
||
if isinstance(child, boxes.TableColumnBox)
|
||
]
|
||
# Rule XXX (not in the spec): column groups have at least
|
||
# one column child.
|
||
if not children:
|
||
children = [boxes.TableColumnBox.anonymous_from(box, [])
|
||
for _i in range(box.span)]
|
||
|
||
# rule 1.3
|
||
if box.tabular_container and len(children) >= 2:
|
||
# TODO: Maybe only remove text if internal is also
|
||
# a proper table descendant of box.
|
||
# This is what the spec says, but maybe not what browsers do:
|
||
# http://lists.w3.org/Archives/Public/www-style/2011Oct/0567
|
||
|
||
# Last child
|
||
internal, text = children[-2:]
|
||
if (internal.internal_table_or_caption and is_whitespace(text)):
|
||
children.pop()
|
||
|
||
# First child
|
||
if len(children) >= 2:
|
||
text, internal = children[:2]
|
||
if (internal.internal_table_or_caption and is_whitespace(text)):
|
||
children.pop(0)
|
||
|
||
# Children other than first and last that would be removed by
|
||
# rule 1.3 are also removed by rule 1.4 below.
|
||
|
||
children = [
|
||
child
|
||
for prev_child, child, next_child in zip(
|
||
[None] + children[:-1],
|
||
children,
|
||
children[1:] + [None]
|
||
)
|
||
if not (
|
||
# Ignore some whitespace: rule 1.4
|
||
prev_child and prev_child.internal_table_or_caption and
|
||
next_child and next_child.internal_table_or_caption and
|
||
is_whitespace(child)
|
||
)
|
||
]
|
||
|
||
if isinstance(box, boxes.TableBox):
|
||
# Rule 2.1
|
||
children = wrap_improper(
|
||
box, children, boxes.TableRowBox,
|
||
lambda child: child.proper_table_child)
|
||
elif isinstance(box, boxes.TableRowGroupBox):
|
||
# Rule 2.2
|
||
children = wrap_improper(box, children, boxes.TableRowBox)
|
||
|
||
if isinstance(box, boxes.TableRowBox):
|
||
# Rule 2.3
|
||
children = wrap_improper(box, children, boxes.TableCellBox)
|
||
else:
|
||
# Rule 3.1
|
||
children = wrap_improper(
|
||
box, children, boxes.TableRowBox,
|
||
lambda child: not isinstance(child, boxes.TableCellBox))
|
||
|
||
# Rule 3.2
|
||
if isinstance(box, boxes.InlineBox):
|
||
children = wrap_improper(
|
||
box, children, boxes.InlineTableBox,
|
||
lambda child: not child.proper_table_child)
|
||
else:
|
||
parent_type = type(box)
|
||
children = wrap_improper(
|
||
box, children, boxes.TableBox,
|
||
lambda child: (not child.proper_table_child or
|
||
parent_type in child.proper_parents))
|
||
|
||
if isinstance(box, boxes.TableBox):
|
||
return wrap_table(box, children)
|
||
else:
|
||
box.children = list(children)
|
||
return box
|
||
|
||
|
||
def wrap_table(box, children):
|
||
"""Take a table box and return it in its table wrapper box.
|
||
|
||
Also re-order children and assign grid positions to each column and cell.
|
||
|
||
Because of colspan/rowspan works, grid_y is implicitly the index of a row,
|
||
but grid_x is an explicit attribute on cells, columns and column group.
|
||
|
||
http://www.w3.org/TR/CSS21/tables.html#model
|
||
http://www.w3.org/TR/CSS21/tables.html#table-layout
|
||
|
||
"""
|
||
# Group table children by type
|
||
columns = []
|
||
rows = []
|
||
all_captions = []
|
||
by_type = {
|
||
boxes.TableColumnBox: columns,
|
||
boxes.TableColumnGroupBox: columns,
|
||
boxes.TableRowBox: rows,
|
||
boxes.TableRowGroupBox: rows,
|
||
boxes.TableCaptionBox: all_captions,
|
||
}
|
||
for child in children:
|
||
by_type[type(child)].append(child)
|
||
|
||
# Split top and bottom captions
|
||
captions = {'top': [], 'bottom': []}
|
||
for caption in all_captions:
|
||
captions[caption.style['caption_side']].append(caption)
|
||
|
||
# Assign X positions on the grid to column boxes
|
||
column_groups = list(wrap_improper(
|
||
box, columns, boxes.TableColumnGroupBox))
|
||
grid_x = 0
|
||
for group in column_groups:
|
||
group.grid_x = grid_x
|
||
if group.children:
|
||
for column in group.children:
|
||
# There's no need to take care of group's span, as "span=x"
|
||
# already generates x TableColumnBox children
|
||
column.grid_x = grid_x
|
||
grid_x += 1
|
||
group.span = len(group.children)
|
||
else:
|
||
grid_x += group.span
|
||
grid_width = grid_x
|
||
|
||
row_groups = wrap_improper(box, rows, boxes.TableRowGroupBox)
|
||
# Extract the optional header and footer groups.
|
||
body_row_groups = []
|
||
header = None
|
||
footer = None
|
||
for group in row_groups:
|
||
display = group.style['display']
|
||
if display == 'table-header-group' and header is None:
|
||
group.is_header = True
|
||
header = group
|
||
elif display == 'table-footer-group' and footer is None:
|
||
group.is_footer = True
|
||
footer = group
|
||
else:
|
||
body_row_groups.append(group)
|
||
row_groups = (
|
||
([header] if header is not None else []) +
|
||
body_row_groups +
|
||
([footer] if footer is not None else []))
|
||
|
||
# Assign a (x,y) position in the grid to each cell.
|
||
# rowspan can not extend beyond a row group, so each row group
|
||
# is independent.
|
||
# http://www.w3.org/TR/CSS21/tables.html#table-layout
|
||
# Column 0 is on the left if direction is ltr, right if rtl.
|
||
# This algorithm does not change.
|
||
grid_height = 0
|
||
for group in row_groups:
|
||
# Indexes: row number in the group.
|
||
# Values: set of cells already occupied by row-spanning cells.
|
||
occupied_cells_by_row = [set() for row in group.children]
|
||
for row in group.children:
|
||
occupied_cells_in_this_row = occupied_cells_by_row.pop(0)
|
||
# The list is now about rows after this one.
|
||
grid_x = 0
|
||
for cell in row.children:
|
||
# Make sure that the first grid cell is free.
|
||
while grid_x in occupied_cells_in_this_row:
|
||
grid_x += 1
|
||
cell.grid_x = grid_x
|
||
new_grid_x = grid_x + cell.colspan
|
||
# http://www.w3.org/TR/html401/struct/tables.html#adef-rowspan
|
||
if cell.rowspan != 1:
|
||
max_rowspan = len(occupied_cells_by_row) + 1
|
||
if cell.rowspan == 0:
|
||
# All rows until the end of the group
|
||
spanned_rows = occupied_cells_by_row
|
||
cell.rowspan = max_rowspan
|
||
else:
|
||
cell.rowspan = min(cell.rowspan, max_rowspan)
|
||
spanned_rows = occupied_cells_by_row[:cell.rowspan - 1]
|
||
spanned_columns = range(grid_x, new_grid_x)
|
||
for occupied_cells in spanned_rows:
|
||
occupied_cells.update(spanned_columns)
|
||
grid_x = new_grid_x
|
||
grid_width = max(grid_width, grid_x)
|
||
grid_height += len(group.children)
|
||
|
||
table = box.copy_with_children(row_groups)
|
||
table.column_groups = tuple(column_groups)
|
||
if table.style['border_collapse'] == 'collapse':
|
||
table.collapsed_border_grid = collapse_table_borders(
|
||
table, grid_width, grid_height)
|
||
|
||
if isinstance(box, boxes.InlineTableBox):
|
||
wrapper_type = boxes.InlineBlockBox
|
||
else:
|
||
wrapper_type = boxes.BlockBox
|
||
|
||
wrapper = wrapper_type.anonymous_from(
|
||
box, captions['top'] + [table] + captions['bottom'])
|
||
wrapper.style = wrapper.style.copy()
|
||
wrapper.is_table_wrapper = True
|
||
# Non-inherited properties of the table element apply to one
|
||
# of the wrapper and the table. The other get the initial value.
|
||
# TODO: put this in a method of the table object
|
||
for name in properties.TABLE_WRAPPER_BOX_PROPERTIES:
|
||
wrapper.style[name] = table.style[name]
|
||
table.style[name] = properties.INITIAL_VALUES[name]
|
||
|
||
return wrapper
|
||
|
||
|
||
TRANSPARENT = tinycss2.color3.parse_color('transparent')
|
||
|
||
|
||
def collapse_table_borders(table, grid_width, grid_height):
|
||
"""Resolve border conflicts for a table in the collapsing border model.
|
||
|
||
Take a :class:`TableBox`; set appropriate border widths on the table,
|
||
column group, column, row group, row, and cell boxes; and return
|
||
a data structure for the resolved collapsed border grid.
|
||
|
||
"""
|
||
if not (grid_width and grid_height):
|
||
# Don’t bother with empty tables
|
||
return [], []
|
||
|
||
style_scores = dict((v, i) for i, v in enumerate(reversed([
|
||
'hidden', 'double', 'solid', 'dashed', 'dotted', 'ridge',
|
||
'outset', 'groove', 'inset', 'none'])))
|
||
style_map = {'inset': 'ridge', 'outset': 'groove'}
|
||
transparent = TRANSPARENT
|
||
weak_null_border = (
|
||
(0, 0, style_scores['none']), ('none', 0, transparent))
|
||
vertical_borders = [[weak_null_border for x in range(grid_width + 1)]
|
||
for y in range(grid_height)]
|
||
horizontal_borders = [[weak_null_border for x in range(grid_width)]
|
||
for y in range(grid_height + 1)]
|
||
|
||
def set_one_border(border_grid, box_style, side, grid_x, grid_y):
|
||
from ..draw import get_color
|
||
|
||
style = box_style['border_%s_style' % side]
|
||
width = box_style['border_%s_width' % side]
|
||
color = get_color(box_style, 'border_%s_color' % side)
|
||
|
||
# http://www.w3.org/TR/CSS21/tables.html#border-conflict-resolution
|
||
score = ((1 if style == 'hidden' else 0), width, style_scores[style])
|
||
|
||
style = style_map.get(style, style)
|
||
previous_score, _ = border_grid[grid_y][grid_x]
|
||
# Strict < so that the earlier call wins in case of a tie.
|
||
if previous_score < score:
|
||
border_grid[grid_y][grid_x] = (score, (style, width, color))
|
||
|
||
def set_borders(box, x, y, w, h):
|
||
style = box.style
|
||
for yy in range(y, y + h):
|
||
set_one_border(vertical_borders, style, 'left', x, yy)
|
||
set_one_border(vertical_borders, style, 'right', x + w, yy)
|
||
for xx in range(x, x + w):
|
||
set_one_border(horizontal_borders, style, 'top', xx, y)
|
||
set_one_border(horizontal_borders, style, 'bottom', xx, y + h)
|
||
|
||
# The order is important here:
|
||
# "A style set on a cell wins over one on a row, which wins over a
|
||
# row group, column, column group and, lastly, table"
|
||
# See http://www.w3.org/TR/CSS21/tables.html#border-conflict-resolution
|
||
strong_null_border = (
|
||
(1, 0, style_scores['hidden']), ('hidden', 0, transparent))
|
||
grid_y = 0
|
||
for row_group in table.children:
|
||
for row in row_group.children:
|
||
for cell in row.children:
|
||
# No border inside of a cell with rowspan or colspan
|
||
for xx in range(cell.grid_x + 1, cell.grid_x + cell.colspan):
|
||
for yy in range(grid_y, grid_y + cell.rowspan):
|
||
vertical_borders[yy][xx] = strong_null_border
|
||
for xx in range(cell.grid_x, cell.grid_x + cell.colspan):
|
||
for yy in range(grid_y + 1, grid_y + cell.rowspan):
|
||
horizontal_borders[yy][xx] = strong_null_border
|
||
# The cell’s own borders
|
||
set_borders(cell, x=cell.grid_x, y=grid_y,
|
||
w=cell.colspan, h=cell.rowspan)
|
||
grid_y += 1
|
||
|
||
grid_y = 0
|
||
for row_group in table.children:
|
||
for row in row_group.children:
|
||
set_borders(row, x=0, y=grid_y, w=grid_width, h=1)
|
||
grid_y += 1
|
||
|
||
grid_y = 0
|
||
for row_group in table.children:
|
||
rowspan = len(row_group.children)
|
||
set_borders(row_group, x=0, y=grid_y, w=grid_width, h=rowspan)
|
||
grid_y += rowspan
|
||
|
||
for column_group in table.column_groups:
|
||
for column in column_group.children:
|
||
set_borders(column, x=column.grid_x, y=0, w=1, h=grid_height)
|
||
|
||
for column_group in table.column_groups:
|
||
set_borders(column_group, x=column_group.grid_x, y=0,
|
||
w=column_group.span, h=grid_height)
|
||
|
||
set_borders(table, x=0, y=0, w=grid_width, h=grid_height)
|
||
|
||
# Now that all conflicts are resolved, set transparent borders of
|
||
# the correct widths on each box. The actual border grid will be
|
||
# painted separately.
|
||
def set_transparent_border(box, side, twice_width):
|
||
box.style['border_%s_style' % side] = 'solid',
|
||
box.style['border_%s_width' % side] = twice_width / 2
|
||
box.style['border_%s_color' % side] = transparent
|
||
|
||
def remove_borders(box):
|
||
set_transparent_border(box, 'top', 0)
|
||
set_transparent_border(box, 'right', 0)
|
||
set_transparent_border(box, 'bottom', 0)
|
||
set_transparent_border(box, 'left', 0)
|
||
|
||
def max_vertical_width(x, y, h):
|
||
return max(
|
||
width for grid_row in vertical_borders[y:y + h]
|
||
for _, (_, width, _) in [grid_row[x]])
|
||
|
||
def max_horizontal_width(x, y, w):
|
||
return max(
|
||
width for _, (_, width, _) in horizontal_borders[y][x:x + w])
|
||
|
||
grid_y = 0
|
||
for row_group in table.children:
|
||
remove_borders(row_group)
|
||
for row in row_group.children:
|
||
remove_borders(row)
|
||
for cell in row.children:
|
||
set_transparent_border(cell, 'top', max_horizontal_width(
|
||
x=cell.grid_x, y=grid_y, w=cell.colspan))
|
||
set_transparent_border(cell, 'bottom', max_horizontal_width(
|
||
x=cell.grid_x, y=grid_y + cell.rowspan, w=cell.colspan))
|
||
set_transparent_border(cell, 'left', max_vertical_width(
|
||
x=cell.grid_x, y=grid_y, h=cell.rowspan))
|
||
set_transparent_border(cell, 'right', max_vertical_width(
|
||
x=cell.grid_x + cell.colspan, y=grid_y, h=cell.rowspan))
|
||
grid_y += 1
|
||
|
||
for column_group in table.column_groups:
|
||
remove_borders(column_group)
|
||
for column in column_group.children:
|
||
remove_borders(column)
|
||
|
||
set_transparent_border(table, 'top', max_horizontal_width(
|
||
x=0, y=0, w=grid_width))
|
||
set_transparent_border(table, 'bottom', max_horizontal_width(
|
||
x=0, y=grid_height, w=grid_width))
|
||
# "UAs must compute an initial left and right border width for the table
|
||
# by examining the first and last cells in the first row of the table."
|
||
# http://www.w3.org/TR/CSS21/tables.html#collapsing-borders
|
||
# ... so h=1, not grid_height:
|
||
set_transparent_border(table, 'left', max_vertical_width(
|
||
x=0, y=0, h=1))
|
||
set_transparent_border(table, 'right', max_vertical_width(
|
||
x=grid_width, y=0, h=1))
|
||
|
||
return vertical_borders, horizontal_borders
|
||
|
||
|
||
def flex_boxes(box):
|
||
"""Remove and add boxes according to the flex model.
|
||
|
||
Take and return a ``Box`` object.
|
||
|
||
See http://www.w3.org/TR/css-flexbox-1/#flex-items
|
||
|
||
"""
|
||
if not isinstance(box, boxes.ParentBox) or box.is_running():
|
||
return box
|
||
|
||
# Do recursion.
|
||
children = [flex_boxes(child) for child in box.children]
|
||
box.children = flex_children(box, children)
|
||
return box
|
||
|
||
|
||
def flex_children(box, children):
|
||
if isinstance(box, boxes.FlexContainerBox):
|
||
flex_children = []
|
||
for child in children:
|
||
if not child.is_absolutely_positioned():
|
||
child.is_flex_item = True
|
||
if isinstance(child, boxes.TextBox) and not child.text.strip(' '):
|
||
# TODO: ignore texts only containing "characters that can be
|
||
# affected by the white-space property"
|
||
# https://www.w3.org/TR/css-flexbox-1/#flex-items
|
||
continue
|
||
if isinstance(child, boxes.InlineLevelBox):
|
||
# TODO: Only create block boxes for text runs, not for other
|
||
# inline level boxes. This is false but currently needed
|
||
# because block_level_width and block_level_layout are called
|
||
# in layout.flex.
|
||
if isinstance(child, boxes.ParentBox):
|
||
anonymous = boxes.BlockBox.anonymous_from(
|
||
box, child.children)
|
||
anonymous.style = child.style
|
||
else:
|
||
anonymous = boxes.BlockBox.anonymous_from(box, [child])
|
||
anonymous.is_flex_item = True
|
||
flex_children.append(anonymous)
|
||
else:
|
||
flex_children.append(child)
|
||
return flex_children
|
||
else:
|
||
return children
|
||
|
||
|
||
def process_whitespace(box, following_collapsible_space=False):
|
||
"""First part of "The 'white-space' processing model".
|
||
|
||
See http://www.w3.org/TR/CSS21/text.html#white-space-model
|
||
http://dev.w3.org/csswg/css3-text/#white-space-rules
|
||
|
||
"""
|
||
if isinstance(box, boxes.TextBox):
|
||
text = box.text
|
||
if not text:
|
||
return following_collapsible_space
|
||
|
||
# Normalize line feeds
|
||
text = re.sub('\r\n?', '\n', text)
|
||
|
||
new_line_collapse = box.style['white_space'] in ('normal', 'nowrap')
|
||
space_collapse = box.style['white_space'] in (
|
||
'normal', 'nowrap', 'pre-line')
|
||
|
||
if space_collapse:
|
||
# \r characters were removed/converted earlier
|
||
text = re.sub('[\t ]*\n[\t ]*', '\n', text)
|
||
|
||
if new_line_collapse:
|
||
# TODO: this should be language-specific
|
||
# Could also replace with a zero width space character (U+200B),
|
||
# or no character
|
||
# CSS3: http://www.w3.org/TR/css3-text/#line-break-transform
|
||
text = text.replace('\n', ' ')
|
||
|
||
if space_collapse:
|
||
text = text.replace('\t', ' ')
|
||
text = re.sub(' +', ' ', text)
|
||
previous_text = text
|
||
if following_collapsible_space and text.startswith(' '):
|
||
text = text[1:]
|
||
box.leading_collapsible_space = True
|
||
following_collapsible_space = previous_text.endswith(' ')
|
||
else:
|
||
following_collapsible_space = False
|
||
|
||
box.text = text
|
||
return following_collapsible_space
|
||
|
||
if isinstance(box, boxes.ParentBox) and not box.is_running():
|
||
for child in box.children:
|
||
if isinstance(child, (boxes.TextBox, boxes.InlineBox)):
|
||
following_collapsible_space = process_whitespace(
|
||
child, following_collapsible_space)
|
||
else:
|
||
process_whitespace(child)
|
||
if child.is_in_normal_flow():
|
||
following_collapsible_space = False
|
||
|
||
return following_collapsible_space
|
||
|
||
|
||
def inline_in_block(box):
|
||
"""Build the structure of lines inside blocks and return a new box tree.
|
||
|
||
Consecutive inline-level boxes in a block container box are wrapped into a
|
||
line box, itself wrapped into an anonymous block box.
|
||
|
||
This line box will be broken into multiple lines later.
|
||
|
||
This is the first case in
|
||
http://www.w3.org/TR/CSS21/visuren.html#anonymous-block-level
|
||
|
||
Eg.::
|
||
|
||
BlockBox[
|
||
TextBox['Some '],
|
||
InlineBox[TextBox['text']],
|
||
BlockBox[
|
||
TextBox['More text'],
|
||
]
|
||
]
|
||
|
||
is turned into::
|
||
|
||
BlockBox[
|
||
AnonymousBlockBox[
|
||
LineBox[
|
||
TextBox['Some '],
|
||
InlineBox[TextBox['text']],
|
||
]
|
||
]
|
||
BlockBox[
|
||
LineBox[
|
||
TextBox['More text'],
|
||
]
|
||
]
|
||
]
|
||
|
||
"""
|
||
if not isinstance(box, boxes.ParentBox) or box.is_running():
|
||
return box
|
||
|
||
box_children = list(box.children)
|
||
|
||
if box_children and box.leading_collapsible_space is False:
|
||
box.leading_collapsible_space = (
|
||
box_children[0].leading_collapsible_space)
|
||
|
||
children = []
|
||
trailing_collapsible_space = False
|
||
for child in box_children:
|
||
# Keep track of removed collapsing spaces for wrap opportunities, and
|
||
# remove empty text boxes.
|
||
# (They may have been emptied by process_whitespace().)
|
||
|
||
if trailing_collapsible_space:
|
||
child.leading_collapsible_space = True
|
||
|
||
if isinstance(child, boxes.TextBox) and not child.text:
|
||
trailing_collapsible_space = child.leading_collapsible_space
|
||
else:
|
||
trailing_collapsible_space = False
|
||
children.append(inline_in_block(child))
|
||
|
||
if box.trailing_collapsible_space is False:
|
||
box.trailing_collapsible_space = trailing_collapsible_space
|
||
|
||
if not isinstance(box, boxes.BlockContainerBox):
|
||
box.children = children
|
||
return box
|
||
|
||
new_line_children = []
|
||
new_children = []
|
||
|
||
for child_box in children:
|
||
assert not isinstance(child_box, boxes.LineBox)
|
||
if new_line_children and child_box.is_absolutely_positioned():
|
||
new_line_children.append(child_box)
|
||
elif isinstance(child_box, boxes.InlineLevelBox) or (
|
||
new_line_children and child_box.is_floated()):
|
||
# Do not append white space at the start of a line:
|
||
# It would be removed during layout.
|
||
if new_line_children or not (
|
||
isinstance(child_box, boxes.TextBox) and
|
||
# Sequence of white-space was collapsed to a single
|
||
# space by process_whitespace().
|
||
child_box.text == ' ' and
|
||
child_box.style['white_space'] in (
|
||
'normal', 'nowrap', 'pre-line')):
|
||
new_line_children.append(child_box)
|
||
else:
|
||
if new_line_children:
|
||
# Inlines are consecutive no more: add this line box
|
||
# and create a new one.
|
||
line_box = boxes.LineBox.anonymous_from(box, new_line_children)
|
||
anonymous = boxes.BlockBox.anonymous_from(box, [line_box])
|
||
new_children.append(anonymous)
|
||
new_line_children = []
|
||
new_children.append(child_box)
|
||
if new_line_children:
|
||
# There were inlines at the end
|
||
line_box = boxes.LineBox.anonymous_from(box, new_line_children)
|
||
if new_children:
|
||
anonymous = boxes.BlockBox.anonymous_from(box, [line_box])
|
||
new_children.append(anonymous)
|
||
else:
|
||
# Only inline-level children: one line box
|
||
new_children.append(line_box)
|
||
|
||
box.children = new_children
|
||
return box
|
||
|
||
|
||
def block_in_inline(box):
|
||
"""Build the structure of blocks inside lines.
|
||
|
||
Inline boxes containing block-level boxes will be broken in two
|
||
boxes on each side on consecutive block-level boxes, each side wrapped
|
||
in an anonymous block-level box.
|
||
|
||
This is the second case in
|
||
http://www.w3.org/TR/CSS21/visuren.html#anonymous-block-level
|
||
|
||
Eg. if this is given::
|
||
|
||
BlockBox[
|
||
LineBox[
|
||
InlineBox[
|
||
TextBox['Hello.'],
|
||
],
|
||
InlineBox[
|
||
TextBox['Some '],
|
||
InlineBox[
|
||
TextBox['text']
|
||
BlockBox[LineBox[TextBox['More text']]],
|
||
BlockBox[LineBox[TextBox['More text again']]],
|
||
],
|
||
BlockBox[LineBox[TextBox['And again.']]],
|
||
]
|
||
]
|
||
]
|
||
|
||
this is returned::
|
||
|
||
BlockBox[
|
||
AnonymousBlockBox[
|
||
LineBox[
|
||
InlineBox[
|
||
TextBox['Hello.'],
|
||
],
|
||
InlineBox[
|
||
TextBox['Some '],
|
||
InlineBox[TextBox['text']],
|
||
]
|
||
]
|
||
],
|
||
BlockBox[LineBox[TextBox['More text']]],
|
||
BlockBox[LineBox[TextBox['More text again']]],
|
||
AnonymousBlockBox[
|
||
LineBox[
|
||
InlineBox[
|
||
]
|
||
]
|
||
],
|
||
BlockBox[LineBox[TextBox['And again.']]],
|
||
AnonymousBlockBox[
|
||
LineBox[
|
||
InlineBox[
|
||
]
|
||
]
|
||
],
|
||
]
|
||
|
||
"""
|
||
if not isinstance(box, boxes.ParentBox) or box.is_running():
|
||
return box
|
||
|
||
new_children = []
|
||
changed = False
|
||
|
||
for child in box.children:
|
||
if isinstance(child, boxes.LineBox):
|
||
assert len(box.children) == 1, (
|
||
'Line boxes should have no '
|
||
'siblings at this stage, got %r.' % box.children)
|
||
stack = None
|
||
while 1:
|
||
new_line, block, stack = _inner_block_in_inline(
|
||
child, skip_stack=stack)
|
||
if block is None:
|
||
break
|
||
anon = boxes.BlockBox.anonymous_from(box, [new_line])
|
||
new_children.append(anon)
|
||
new_children.append(block_in_inline(block))
|
||
# Loop with the same child and the new stack.
|
||
if new_children:
|
||
# Some children were already added, this became a block
|
||
# context.
|
||
new_child = boxes.BlockBox.anonymous_from(box, [new_line])
|
||
else:
|
||
# Keep the single line box as-is, without anonymous blocks.
|
||
new_child = new_line
|
||
else:
|
||
# Not in an inline formatting context.
|
||
new_child = block_in_inline(child)
|
||
|
||
if new_child is not child:
|
||
changed = True
|
||
new_children.append(new_child)
|
||
|
||
if changed:
|
||
box.children = new_children
|
||
return box
|
||
|
||
|
||
def _inner_block_in_inline(box, skip_stack=None):
|
||
"""Find a block-level box in an inline formatting context.
|
||
|
||
If one is found, return ``(new_box, block_level_box, resume_at)``.
|
||
``new_box`` contains all of ``box`` content before the block-level box.
|
||
``resume_at`` can be passed as ``skip_stack`` in a new call to
|
||
this function to resume the search just after the block-level box.
|
||
|
||
If no block-level box is found after the position marked by
|
||
``skip_stack``, return ``(new_box, None, None)``
|
||
|
||
"""
|
||
new_children = []
|
||
block_level_box = None
|
||
resume_at = None
|
||
changed = False
|
||
|
||
is_start = skip_stack is None
|
||
if is_start:
|
||
skip = 0
|
||
else:
|
||
skip, skip_stack = skip_stack
|
||
|
||
for i, child in enumerate(box.children[skip:]):
|
||
index = i + skip
|
||
if isinstance(child, boxes.BlockLevelBox) and \
|
||
child.is_in_normal_flow():
|
||
assert skip_stack is None # Should not skip here
|
||
block_level_box = child
|
||
index += 1 # Resume *after* the block
|
||
else:
|
||
if isinstance(child, boxes.InlineBox):
|
||
recursion = _inner_block_in_inline(child, skip_stack)
|
||
skip_stack = None
|
||
new_child, block_level_box, resume_at = recursion
|
||
else:
|
||
assert skip_stack is None # Should not skip here
|
||
new_child = block_in_inline(child)
|
||
# block_level_box is still None.
|
||
if new_child is not child:
|
||
changed = True
|
||
new_children.append(new_child)
|
||
if block_level_box is not None:
|
||
resume_at = (index, resume_at)
|
||
box = box.copy_with_children(
|
||
new_children, is_start=is_start, is_end=False)
|
||
break
|
||
else:
|
||
if changed or skip:
|
||
box = box.copy_with_children(
|
||
new_children, is_start=is_start, is_end=True)
|
||
|
||
return box, block_level_box, resume_at
|
||
|
||
|
||
def set_viewport_overflow(root_box):
|
||
"""
|
||
Set a ``viewport_overflow`` attribute on the box for the root element.
|
||
|
||
Like backgrounds, ``overflow`` on the root element must be propagated
|
||
to the viewport.
|
||
|
||
See http://www.w3.org/TR/CSS21/visufx.html#overflow
|
||
"""
|
||
chosen_box = root_box
|
||
if (root_box.element_tag.lower() == 'html' and
|
||
root_box.style['overflow'] == 'visible'):
|
||
for child in root_box.children:
|
||
if child.element_tag.lower() == 'body':
|
||
chosen_box = child
|
||
break
|
||
|
||
root_box.viewport_overflow = chosen_box.style['overflow']
|
||
chosen_box.style['overflow'] = 'visible'
|
||
return root_box
|
||
|
||
|
||
def box_text(box):
|
||
if isinstance(box, boxes.TextBox):
|
||
return box.text
|
||
elif isinstance(box, boxes.ParentBox):
|
||
return ''.join(
|
||
child.text for child in box.descendants()
|
||
if not child.element_tag.endswith('::before') and
|
||
not child.element_tag.endswith('::after') and
|
||
not child.element_tag.endswith('::marker') and
|
||
isinstance(child, boxes.TextBox))
|
||
else:
|
||
return ''
|
||
|
||
|
||
def box_text_first_letter(box):
|
||
# TODO: use the same code as in inlines.first_letter_to_box
|
||
character_found = False
|
||
first_letter = ''
|
||
text = box_text(box)
|
||
while text:
|
||
next_letter = text[0]
|
||
category = unicodedata.category(next_letter)
|
||
if category not in ('Ps', 'Pe', 'Pi', 'Pf', 'Po'):
|
||
if character_found:
|
||
break
|
||
character_found = True
|
||
first_letter += next_letter
|
||
text = text[1:]
|
||
return first_letter
|
||
|
||
|
||
def box_text_before(box):
|
||
if isinstance(box, boxes.ParentBox):
|
||
return ''.join(
|
||
box_text(child) for child in box.descendants()
|
||
if child.element_tag.endswith('::before') and
|
||
not isinstance(child, boxes.ParentBox))
|
||
else:
|
||
return ''
|
||
|
||
|
||
def box_text_after(box):
|
||
if isinstance(box, boxes.ParentBox):
|
||
return ''.join(
|
||
box_text(child) for child in box.descendants()
|
||
if child.element_tag.endswith('::after') and
|
||
not isinstance(child, boxes.ParentBox))
|
||
else:
|
||
return ''
|
||
|
||
|
||
TEXT_CONTENT_EXTRACTORS = {
|
||
'text': box_text,
|
||
'content': box_text,
|
||
'before': box_text_before,
|
||
'after': box_text_after,
|
||
'first-letter': box_text_first_letter}
|