Use bleed area for page’s painting area

Also use border box for canvas.

Fix Kozea#1943.

tests/draw/test_background.py

@@ -1054,13 +1054,14 @@ def test_background_size_clip(assert_pixels):
 
 @assert_no_logs
 def test_bleed_background_size_clip(assert_pixels):
+ # Regression test for https://github.com/Kozea/WeasyPrint/issues/1943
  assert_pixels('''
- RRRRRR
- RBBBBR
- RBRBBR
- RBBBBR
- RBBBBR
- RRRRRR
+ BBBBBB
+ BBBBBB
+ BBRBBB
+ BBBBBB
+ BBBBBB
+ BBBBBB
  ''', '''
  <style>
  @page { size: 4px; bleed: 1px; margin: 1px;

weasyprint/draw.py

@@ -55,14 +55,11 @@ def lighten(color):
 
 def draw_page(page, stream):
  """Draw the given PageBox."""
- bleed = {
- side: page.style[f'bleed_{side}'].value
- for side in ('top', 'right', 'bottom', 'left')}
  marks = page.style['marks']
  stacking_context = StackingContext.from_page(page)
  draw_background(
- stream, stacking_context.box.background, clip_box=False, bleed=bleed,
- marks=marks)
+ stream, stacking_context.box.background, clip_box=False,
+ bleed=page.bleed, marks=marks)
  draw_background(stream, page.canvas_background, clip_box=False)
  draw_border(stream, page)
  draw_stacking_context(stream, stacking_context)
@@ -249,26 +246,14 @@ def draw_background(stream, bg, clip_box=True, bleed=None, marks=()):
  stream.set_color_rgb(*bg.color[:3])
  stream.set_alpha(bg.color.alpha)
  painting_area = bg.layers[-1].painting_area
- if painting_area:
- if bleed:
- # Painting area is the PDF BleedBox
- x, y, width, height = painting_area
- painting_area = (
- x - bleed['left'], y - bleed['top'],
- width + bleed['left'] + bleed['right'],
- height + bleed['top'] + bleed['bottom'])
- stream.rectangle(*painting_area)
- stream.clip()
- stream.end()
+ stream.rectangle(*painting_area)
+ stream.clip()
+ stream.end()
  stream.rectangle(*painting_area)
  stream.fill()
 
  if bleed and marks:
  x, y, width, height = bg.layers[-1].painting_area
- x -= bleed['left']
- y -= bleed['top']
- width += bleed['left'] + bleed['right']
- height += bleed['top'] + bleed['bottom']
  half_bleed = {key: value * 0.5 for key, value in bleed.items()}
  svg = f'''
  <svg height="{height}" width="{width}"

weasyprint/formatting_structure/boxes.py

@@ -722,6 +722,19 @@ def __init__(self, page_type, style):
  def __repr__(self):
  return f'<{type(self).__name__} {self.page_type}>'
 
+ @property
+ def bleed(self):
+ return {
+ side: self.style[f'bleed_{side}'].value
+ for side in ('top', 'right', 'bottom', 'left')}
+
+ @property
+ def bleed_area(self):
+ return (
+ -self.bleed['left'], -self.bleed['top'],
+ self.margin_width() + self.bleed['left'] + self.bleed['right'],
+ self.margin_height() + self.bleed['top'] + self.bleed['bottom'])
+
 
 class MarginBox(BlockContainerBox):
  """Box in page margins, as defined in CSS3 Paged Media"""

weasyprint/layout/background.py

@@ -82,9 +82,11 @@ def layout_background_layer(box, page, resolution, image, size, clip, repeat,
  clipped_boxes = []
  painting_area = 0, 0, 0, 0
  if box is page:
- painting_area = 0, 0, page.margin_width(), page.margin_height()
- # XXX: how does border-radius work on pages?
- clipped_boxes = [box.rounded_border_box()]
+ # [The page’s] background painting area is the bleed area […]
+ # regardless of background-clip.
+ # https://drafts.csswg.org/css-page-3/#painting
+ painting_area = page.bleed_area
+ clipped_boxes = []
  elif isinstance(box, boxes.TableRowGroupBox):
  clipped_boxes = []
  total_height = 0
@@ -215,13 +217,13 @@ def layout_backgrounds(page, get_image_from_uri):
  break
 
  if chosen_box.background:
- painting_area = box_rectangle(page, 'padding-box')
+ painting_area = box_rectangle(page, 'border-box')
  original_background = page.background
  layout_box_backgrounds(
  page, page, get_image_from_uri, layout_children=False,
  style=chosen_box.style)
  page.canvas_background = page.background._replace(
- # TODO: shouldn’t background-clip be considered here?
+ # TODO: background-clip should be updated
  layers=[
  layer._replace(painting_area=painting_area)
  for layer in page.background.layers])