Auto merge of #7829 - frewsxcv:htmltablecellelement-cellindex, r=Ms2ger

Implement HTMLTableCellElement::CellIndex

Extracted from #6936

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5 files changed, 29 insertions, 28 deletions

diff --git a/components/script/dom/htmltablecellelement.rs b/components/script/dom/htmltablecellelement.rs
index 7be54174eae..d377d1cee3d 100644
--- a/components/script/dom/htmltablecellelement.rs
+++ b/components/script/dom/htmltablecellelement.rs
@@ -5,7 +5,11 @@
 use cssparser::RGBA;
 use dom::attr::{Attr, AttrValue};
 use dom::bindings::codegen::Bindings::HTMLTableCellElementBinding::HTMLTableCellElementMethods;
-use dom::bindings::codegen::InheritTypes::{HTMLElementCast, HTMLTableCellElementDerived};
+use dom::bindings::codegen::Bindings::NodeBinding::NodeMethods;
+use dom::bindings::codegen::InheritTypes::HTMLElementCast;
+use dom::bindings::codegen::InheritTypes::HTMLTableCellElementDerived;
+use dom::bindings::codegen::InheritTypes::HTMLTableRowElementDerived;
+use dom::bindings::codegen::InheritTypes::NodeCast;
 use dom::bindings::js::LayoutJS;
 use dom::document::Document;
 use dom::element::{AttributeMutation, ElementTypeId};
@@ -78,6 +82,20 @@ impl HTMLTableCellElementMethods for HTMLTableCellElement {
 
     // https://html.spec.whatwg.org/multipage/#dom-tdth-colspan
     make_uint_setter!(SetColSpan, "colspan");
+
+    // https://html.spec.whatwg.org/multipage/#dom-tdth-cellindex
+    fn CellIndex(&self) -> i32 {
+        let self_node = NodeCast::from_ref(self);
+
+        let parent_children = match self_node.GetParentNode() {
+            Some(ref parent_node) if parent_node.is_htmltablerowelement() => parent_node.children(),
+            _ => return -1,
+        };
+
+        parent_children.filter(|c| c.is_htmltablecellelement())
+                       .position(|c| c.r() == self_node)
+                       .map(|p| p as i32).unwrap_or(-1)
+    }
 }
 
 
diff --git a/components/script/dom/webidls/HTMLTableCellElement.webidl b/components/script/dom/webidls/HTMLTableCellElement.webidl
index 0f3a2a6a14f..7db825376c4 100644
--- a/components/script/dom/webidls/HTMLTableCellElement.webidl
+++ b/components/script/dom/webidls/HTMLTableCellElement.webidl
@@ -9,7 +9,7 @@ interface HTMLTableCellElement : HTMLElement {
              attribute unsigned long colSpan;
   //         attribute unsigned long rowSpan;
   //[PutForwards=value] readonly attribute DOMSettableTokenList headers;
-  //readonly attribute long cellIndex;
+  readonly attribute long cellIndex;
 
   // also has obsolete members
 };
diff --git a/tests/wpt/metadata/html/dom/interfaces.html.ini b/tests/wpt/metadata/html/dom/interfaces.html.ini
index 123d9c48d66..4f62c39b96a 100644
--- a/tests/wpt/metadata/html/dom/interfaces.html.ini
+++ b/tests/wpt/metadata/html/dom/interfaces.html.ini
@@ -4770,9 +4770,6 @@
   [HTMLTableCellElement interface: document.createElement("td") must inherit property "headers" with the proper type (2)]
     expected: FAIL
 
-  [HTMLTableCellElement interface: document.createElement("td") must inherit property "cellIndex" with the proper type (3)]
-    expected: FAIL
-
   [HTMLTableCellElement interface: document.createElement("td") must inherit property "align" with the proper type (4)]
     expected: FAIL
 
@@ -4833,9 +4830,6 @@
   [HTMLTableCellElement interface: document.createElement("th") must inherit property "headers" with the proper type (2)]
     expected: FAIL
 
-  [HTMLTableCellElement interface: document.createElement("th") must inherit property "cellIndex" with the proper type (3)]
-    expected: FAIL
-
   [HTMLTableCellElement interface: document.createElement("th") must inherit property "align" with the proper type (4)]
     expected: FAIL
 
@@ -4872,9 +4866,6 @@
   [HTMLTableCellElement interface: attribute headers]
     expected: FAIL
 
-  [HTMLTableCellElement interface: attribute cellIndex]
-    expected: FAIL
-
   [HTMLTableCellElement interface: attribute align]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/html/semantics/tabular-data/attributes-common-to-td-and-th-elements/cellIndex.html.ini b/tests/wpt/metadata/html/semantics/tabular-data/attributes-common-to-td-and-th-elements/cellIndex.html.ini
deleted file mode 100644
index 516b739b45a..00000000000
--- a/tests/wpt/metadata/html/semantics/tabular-data/attributes-common-to-td-and-th-elements/cellIndex.html.ini
+++ /dev/null
@@ -1,17 +0,0 @@
-[cellIndex.html]
-  type: testharness
-  [cellIndex should exist.]
-    expected: FAIL
-
-  [For cells without a parent, cellIndex should be -1.]
-    expected: FAIL
-
-  [For cells whose parent is not a tr, cellIndex should be -1.]
-    expected: FAIL
-
-  [For cells whose parent is not a HTML tr, cellIndex should be -1.]
-    expected: FAIL
-
-  [For cells whose parent is a tr, cellIndex should be the index.]
-    expected: FAIL
-
diff --git a/tests/wpt/web-platform-tests/html/semantics/tabular-data/attributes-common-to-td-and-th-elements/cellIndex.html b/tests/wpt/web-platform-tests/html/semantics/tabular-data/attributes-common-to-td-and-th-elements/cellIndex.html
index b9e523334f3..b8449229d5b 100644
--- a/tests/wpt/web-platform-tests/html/semantics/tabular-data/attributes-common-to-td-and-th-elements/cellIndex.html
+++ b/tests/wpt/web-platform-tests/html/semantics/tabular-data/attributes-common-to-td-and-th-elements/cellIndex.html
@@ -38,4 +38,13 @@ test(function() {
   var td = tr.appendChild(document.createElement("td"));
   assert_equals(td.cellIndex, 1);
 }, "For cells whose parent is a tr, cellIndex should be the index.")
+test(function() {
+  var tr = document.createElement("tr");
+  var th = tr.appendChild(document.createElement("th"));
+  assert_equals(th.cellIndex, 0);
+  tr.appendChild(document.createElement("div"));
+  tr.appendChild(document.createTextNode("Hello World"));
+  var td = tr.appendChild(document.createElement("td"));
+  assert_equals(td.cellIndex, 1)
+}, "For cells whose parent is a tr with non td/th sibling, cellIndex should skip those non td/th siblings.")
 </script>