flexbox: initial attempt to add support for RTL direction

weasyprint/tests/test_layout/test_flex.py

@@ -58,7 +58,9 @@ def test_flex_direction_row_rtl():
         div_2.position_y ==
         div_3.position_y ==
         article.position_y)
-    assert div_1.position_x == article.width - div_1.padding_width()
+    assert (
+        div_1.position_x + div_1.width ==
+        article.position_x + article.width)
     assert div_1.position_x > div_2.position_x > div_3.position_x
 
 
@@ -111,10 +113,7 @@ def test_flex_direction_row_reverse_rtl():
         div_2.position_y ==
         div_3.position_y ==
         article.position_y)
-    # below assert needs to be fixed
-    assert (
-        div_3.position_x + div_3.width ==
-        article.position_x + article.width)
+    assert div_3.position_x == article.position_x
     assert div_1.position_x > div_2.position_x > div_3.position_x
 
 
@@ -143,6 +142,32 @@ def test_flex_direction_column():
     assert div_1.position_y < div_2.position_y < div_3.position_y
 
 
+@assert_no_logs
+def test_flex_direction_column_rtl():
+    page, = render_pages('''
+      <article style="display: flex; flex-direction: column;
+      direction: rtl">
+        <div>A</div>
+        <div>B</div>
+        <div>C</div>
+      </article>
+    ''')
+    html, = page.children
+    body, = html.children
+    article, = body.children
+    div_1, div_2, div_3 = article.children
+    assert div_1.children[0].children[0].text == 'A'
+    assert div_2.children[0].children[0].text == 'B'
+    assert div_3.children[0].children[0].text == 'C'
+    assert (
+        div_1.position_x ==
+        div_2.position_x ==
+        div_3.position_x ==
+        article.position_x)
+    assert div_1.position_y == article.position_y
+    assert div_1.position_y < div_2.position_y < div_3.position_y
+
+
 @assert_no_logs
 def test_flex_direction_column_reverse():
     page, = render_pages('''
@@ -170,6 +195,34 @@ def test_flex_direction_column_reverse():
     assert div_1.position_y < div_2.position_y < div_3.position_y
 
 
+@assert_no_logs
+def test_flex_direction_column_reverse_rtl():
+    page, = render_pages('''
+      <article style="display: flex; flex-direction: column-reverse;
+      direction: rtl">
+        <div>A</div>
+        <div>B</div>
+        <div>C</div>
+      </article>
+    ''')
+    html, = page.children
+    body, = html.children
+    article, = body.children
+    div_1, div_2, div_3 = article.children
+    assert div_1.children[0].children[0].text == 'C'
+    assert div_2.children[0].children[0].text == 'B'
+    assert div_3.children[0].children[0].text == 'A'
+    assert (
+        div_1.position_x ==
+        div_2.position_x ==
+        div_3.position_x ==
+        article.position_x)
+    assert (
+        div_3.position_y + div_3.height ==
+        article.position_y + article.height)
+    assert div_1.position_y < div_2.position_y < div_3.position_y
+
+
 @assert_no_logs
 def test_flex_row_wrap():
     page, = render_pages('''