From 965d46df73bd39059c23ae4469c3cc6f7d963c0f Mon Sep 17 00:00:00 2001
From: Guillaume Ayoub <guillaume@courtbouillon.org>
Date: Sun, 5 Sep 2021 17:50:44 +0200
Subject: [PATCH] Create a dedicated function to find last in-flow child

---
 weasyprint/layout/blocks.py | 26 ++++++++++----------------
 1 file changed, 10 insertions(+), 16 deletions(-)

diff --git a/weasyprint/layout/blocks.py b/weasyprint/layout/blocks.py
index 5fed13e4..0d31d885 100644
--- a/weasyprint/layout/blocks.py
+++ b/weasyprint/layout/blocks.py
@@ -341,10 +341,7 @@ def block_container_layout(context, box, max_position_y, skip_stack,
                     new_child.index = index
                     new_children.append(new_child)
                 else:
-                    for previous_child in reversed(new_children):
-                        if previous_child.is_in_normal_flow():
-                            last_in_flow_child = previous_child
-                            break
+                    last_in_flow_child = find_last_in_flow_child(new_children)
                     page_break = block_level_page_break(
                         last_in_flow_child, child)
                     if new_children and page_break in ('avoid', 'avoid-page'):
@@ -445,12 +442,7 @@ def block_container_layout(context, box, max_position_y, skip_stack,
             if is_page_break:
                 break
         else:
-            for previous_child in reversed(new_children):
-                if previous_child.is_in_normal_flow():
-                    last_in_flow_child = previous_child
-                    break
-            else:
-                last_in_flow_child = None
+            last_in_flow_child = find_last_in_flow_child(new_children)
             if last_in_flow_child is not None:
                 # Between in-flow siblings
                 page_break = block_level_page_break(last_in_flow_child, child)
@@ -618,12 +610,7 @@ def block_container_layout(context, box, max_position_y, skip_stack,
         box.position_y += (
             collapse_margin(this_box_adjoining_margins) - box.margin_top)
 
-    for previous_child in reversed(new_children):
-        if previous_child.is_in_normal_flow():
-            last_in_flow_child = previous_child
-            break
-    else:
-        last_in_flow_child = None
+    last_in_flow_child = find_last_in_flow_child(new_children)
     collapsing_through = False
     if last_in_flow_child is None:
         collapsed_margin = collapse_margin(adjoining_margins)
@@ -872,6 +859,13 @@ def find_earlier_page_break(children, absolute_boxes, fixed_boxes):
     return new_children, resume_at
 
 
+def find_last_in_flow_child(children):
+    """Find and return the last in-flow child of given ``children``."""
+    for child in reversed(children):
+        if child.is_in_normal_flow():
+            return child
+
+
 def reversed_enumerate(seq):
     """Like reversed(list(enumerate(seq))) without copying the whole seq."""
     return zip(reversed(range(len(seq))), reversed(seq))