Merge pull request #2087 from kygoh/css-tables-3-width

Use CSS Table Module Level 3 to compute widths

tests/layout/test_table.py

@@ -515,7 +515,7 @@ def test_layout_table_auto_8():
 @assert_no_logs
 def test_layout_table_auto_9():
     page, = render_pages('''
-      <table style="border-spacing: 10px; width: 110px; margin: 5px">
+      <table style="border-spacing: 10px; width: 120px; margin: 5px">
         <tr>
           <td style="width: 60px"></td>
           <td></td>
@@ -1113,8 +1113,8 @@ def test_layout_table_auto_31():
 def test_layout_table_auto_32():
     # Table with a cell larger than the table's width
     page, = render_pages('''
-      <table style="width: 300px; margin: 100px">
-        <td style="width: 400px"></td>
+      <table style="width: 400px; margin: 100px">
+        <td style="width: 500px"></td>
       </table>
     ''')
     html, = page.children

weasyprint/layout/preferred.py

@@ -256,13 +256,7 @@ def table_cell_min_content_width(context, box, outer):
         outer,
         max(children_widths) if children_widths else 0)
 
-    width = box.style['width']
-    if width != 'auto' and width.unit == 'px':
-        cell_min_width = adjust(box, outer, width.value)
-    else:
-        cell_min_width = 0
-
-    return max(children_min_width, cell_min_width)
+    return children_min_width
 
 
 def table_cell_max_content_width(context, box, outer):

weasyprint/layout/table.py

@@ -753,6 +753,7 @@ def auto_table_layout(context, box, containing_block):
     guesses = (
         min_content_guess, min_content_percentage_guess,
         min_content_specified_guess, max_content_guess)
+    # https://www.w3.org/TR/css-tables-3/#width-distribution-algorithm
     for i in range(len(grid)):
         if column_intrinsic_percentages[i]:
             min_content_percentage_guess[i] = max(
@@ -761,7 +762,9 @@ def auto_table_layout(context, box, containing_block):
             min_content_specified_guess[i] = min_content_percentage_guess[i]
             max_content_guess[i] = min_content_percentage_guess[i]
         elif constrainedness[i]:
-            min_content_specified_guess[i] = column_min_content_widths[i]
+            # any other column that is constrained is assigned
+            # its max-content width
+            min_content_specified_guess[i] = column_max_content_widths[i]
 
     if assignable_width <= sum(max_content_guess):
         # Default values shouldn't be used, but we never know.