Auto merge of #5885 - mbrubeck:empty-table, r=pcwalton

r? @pcwalton

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5 files changed, 50 insertions, 8 deletions

diff --git a/components/layout/table.rs b/components/layout/table.rs
index 25d17d04b8f..80edfa2742e 100644
--- a/components/layout/table.rs
+++ b/components/layout/table.rs
@@ -202,6 +202,14 @@ impl TableFlow {
             }
         }
     }
+
+    pub fn total_horizontal_spacing(&self) -> Au {
+        let num_columns = self.column_intrinsic_inline_sizes.len();
+        if num_columns == 0 {
+            return Au(0);
+        }
+        self.spacing().horizontal * (num_columns as i32 + 1)
+    }
 }
 
 impl Flow for TableFlow {
@@ -396,9 +404,8 @@ impl Flow for TableFlow {
             }
         }
 
-        let spacing = self.spacing().horizontal *
-            (self.column_intrinsic_inline_sizes.len() as i32 + 1);
-        computation.surrounding_size = computation.surrounding_size + spacing;
+        computation.surrounding_size = computation.surrounding_size +
+                                       self.total_horizontal_spacing();
 
         self.block_flow.base.intrinsic_inline_sizes = computation.finish()
     }
@@ -435,8 +442,7 @@ impl Flow for TableFlow {
         let inline_end_content_edge = self.block_flow.fragment.border_padding.inline_end;
         let padding_and_borders = self.block_flow.fragment.border_padding.inline_start_end();
         let spacing_per_cell = self.spacing();
-        let spacing = spacing_per_cell.horizontal *
-            (self.column_intrinsic_inline_sizes.len() as i32 + 1);
+        let spacing = self.total_horizontal_spacing();
         let content_inline_size =
             self.block_flow.fragment.border_box.size.inline - padding_and_borders - spacing;
 
@@ -785,6 +791,7 @@ impl TableLikeFlow for BlockFlow {
             // Our current border-box position.
             let block_start_border_padding = self.fragment.border_padding.block_start;
             let mut current_block_offset = block_start_border_padding;
+            let mut has_rows = false;
 
             // At this point, `current_block_offset` is at the content edge of our box. Now iterate
             // over children.
@@ -795,6 +802,7 @@ impl TableLikeFlow for BlockFlow {
 
                 // Account for spacing or collapsed borders.
                 if kid.is_table_row() {
+                    has_rows = true;
                     let child_table_row = kid.as_table_row();
                     current_block_offset = current_block_offset +
                         match self.fragment.style.get_inheritedtable().border_collapse {
@@ -843,7 +851,7 @@ impl TableLikeFlow for BlockFlow {
 
             // Take border, padding, and spacing into account.
             let block_end_offset = self.fragment.border_padding.block_end +
-                block_direction_spacing;
+                if has_rows { block_direction_spacing } else { Au(0) };
             current_block_offset = current_block_offset + block_end_offset;
 
             // Now that `current_block_offset` is at the block-end of the border box, compute the
diff --git a/components/layout/table_wrapper.rs b/components/layout/table_wrapper.rs
index 5e321382e97..a336ca55cfb 100644
--- a/components/layout/table_wrapper.rs
+++ b/components/layout/table_wrapper.rs
@@ -95,8 +95,7 @@ impl TableWrapperFlow {
         for kid in self.block_flow.base.child_iter() {
             if kid.is_table() {
                 let kid_table = kid.as_table();
-                let spacing_per_cell = kid_table.spacing().horizontal;
-                spacing = spacing_per_cell * (self.column_intrinsic_inline_sizes.len() as i32 + 1);
+                spacing = kid_table.total_horizontal_spacing();
                 table_border_padding =
                     kid_table.block_flow.fragment.border_padding.inline_start_end();
                 break
diff --git a/tests/ref/basic.list b/tests/ref/basic.list
index 635d79798de..a74da9f7fe0 100644
--- a/tests/ref/basic.list
+++ b/tests/ref/basic.list
@@ -86,6 +86,7 @@ flaky_cpu == append_style_a.html append_style_b.html
 == border_radius_overlapping_a.html border_radius_overlapping_ref.html
 == border_spacing_a.html border_spacing_ref.html
 == border_spacing_auto_layout_a.html border_spacing_ref.html
+== border_spacing_empty_table.html border_spacing_empty_table_ref.html
 == border_spacing_fixed_layout_a.html border_spacing_ref.html
 == border_style_none_a.html border_style_none_b.html
 == borders_a.html borders_b.html
diff --git a/tests/ref/border_spacing_empty_table.html b/tests/ref/border_spacing_empty_table.html
new file mode 100644
index 00000000000..d1ee2cc66c3
--- /dev/null
+++ b/tests/ref/border_spacing_empty_table.html
@@ -0,0 +1,19 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta charset="UTF-8">
+    <style>
+      body {
+        background: yellow;
+      }
+      table {
+        border-spacing: 100px;
+        background: darkblue;
+      }
+    </style>
+  </head>
+  <body>
+    <table></table>
+  </body>
+</html>
+
diff --git a/tests/ref/border_spacing_empty_table_ref.html b/tests/ref/border_spacing_empty_table_ref.html
new file mode 100644
index 00000000000..727795d8e38
--- /dev/null
+++ b/tests/ref/border_spacing_empty_table_ref.html
@@ -0,0 +1,15 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta charset="UTF-8">
+    <style>
+      body {
+        background: yellow;
+      }
+    </style>
+  </head>
+  <body>
+  </body>
+</html>
+
+