Always use absolute paths to get hrefs in SVG

Also be more fault-tolerant when trying to render use tags.

Fix #1531.

weasyprint/svg/__init__.py

@@ -12,6 +12,7 @@
 
 from cssselect2 import ElementWrapper
 
+from ..urls import get_url_attribute
 from .bounding_box import bounding_box, is_valid_bounding_box
 from .css import parse_declarations, parse_stylesheets
 from .defs import (
@@ -175,9 +176,12 @@ def get_viewbox(self):
             return tuple(
                 float(number) for number in normalize(viewbox).split())
 
-    def get_href(self):
+    def get_href(self, base_url):
         """Get the href attribute, with or without a namespace."""
-        return self.get('{http://www.w3.org/1999/xlink}href', self.get('href'))
+        for attr_name in ('{http://www.w3.org/1999/xlink}href', 'href'):
+            url = get_url_attribute(self, attr_name, base_url)
+            if url:
+                return url
 
     @staticmethod
     def process_whitespace(string, preserve):

weasyprint/svg/defs.py

@@ -25,14 +25,14 @@ def use(svg, node, font_size):
         if attribute in node.attrib:
             del node.attrib[attribute]
 
-    parsed_url = parse_url(node.get_href())
-    if parsed_url.fragment and not parsed_url.path:
+    parsed_url = parse_url(node.get_href(svg.url))
+    if parsed_url.fragment and parsed_url[:3] == parse_url(svg.url)[:3]:
         if parsed_url.fragment in svg.use_cache:
             tree = svg.use_cache[parsed_url.fragment].copy()
         else:
             try:
                 tree = svg.tree.get_child(parsed_url.fragment).copy()
-            except AttributeError:
+            except Exception:
                 return
             else:
                 svg.use_cache[parsed_url.fragment] = tree
@@ -41,7 +41,7 @@ def use(svg, node, font_size):
         try:
             bytestring_svg = svg.url_fetcher(url)
             use_svg = SVG(bytestring_svg, url)
-        except TypeError:
+        except Exception:
             return
         else:
             use_svg.get_intrinsic_size(font_size)

weasyprint/svg/images.py

@@ -6,8 +6,6 @@
 
 """
 
-from urllib.parse import urljoin
-
 from .utils import preserve_ratio
 
 
@@ -34,7 +32,7 @@ def image(svg, node, font_size):
     x, y = svg.point(node.get('x'), node.get('y'), font_size)
     svg.stream.transform(e=x, f=y)
     base_url = node.get('{http://www.w3.org/XML/1998/namespace}base')
-    url = urljoin(base_url or svg.url, node.get_href())
+    url = node.get_href(base_url or svg.url)
     image = svg.context.get_image_from_uri(url=url, forced_mime_type='image/*')
     if image is None:
         return