From 01c42693d425c2c779438f2a0f3bd419f948e4b7 Mon Sep 17 00:00:00 2001
From: Cameron McCormack <cam@mcc.id.au>
Date: Fri, 6 May 2016 16:01:14 +1000
Subject: [PATCH] Add Servo_InheritComputedValues.

---
 ports/geckolib/bindings.rs        |  2 ++
 ports/geckolib/glue.rs            | 10 ++++++++++
 ports/geckolib/properties.mako.rs | 32 ++++++++++++++++++-------------
 3 files changed, 31 insertions(+), 13 deletions(-)

diff --git a/ports/geckolib/bindings.rs b/ports/geckolib/bindings.rs
index 618c049bafc..df04e0f0ccc 100644
--- a/ports/geckolib/bindings.rs
+++ b/ports/geckolib/bindings.rs
@@ -104,6 +104,8 @@ extern "C" {
                                                    set: *mut RawServoStyleSet,
                                                    is_probe: bool)
      -> *mut ServoComputedValues;
+    pub fn Servo_InheritComputedValues(parent_style: *mut ServoComputedValues)
+     -> *mut ServoComputedValues;
     pub fn Servo_AddRefComputedValues(arg1: *mut ServoComputedValues);
     pub fn Servo_ReleaseComputedValues(arg1: *mut ServoComputedValues);
     pub fn Gecko_GetAttrAsUTF8(element: *mut RawGeckoElement, ns: *const u8,
diff --git a/ports/geckolib/glue.rs b/ports/geckolib/glue.rs
index d0b75941bdd..fb8c99d597e 100644
--- a/ports/geckolib/glue.rs
+++ b/ports/geckolib/glue.rs
@@ -342,6 +342,16 @@ pub extern "C" fn Servo_GetComputedValuesForPseudoElement(parent_style: *mut Ser
     }
 }
 
+#[no_mangle]
+pub extern "C" fn Servo_InheritComputedValues(parent_style: *mut ServoComputedValues)
+     -> *mut ServoComputedValues {
+    type Helpers = ArcHelpers<ServoComputedValues, GeckoComputedValues>;
+    Helpers::with(parent_style, |parent| {
+        let style = GeckoComputedValues::inherit_from(parent);
+        Helpers::from(style)
+    })
+}
+
 #[no_mangle]
 pub extern "C" fn Servo_AddRefComputedValues(ptr: *mut ServoComputedValues) -> () {
     type Helpers = ArcHelpers<ServoComputedValues, GeckoComputedValues>;
diff --git a/ports/geckolib/properties.mako.rs b/ports/geckolib/properties.mako.rs
index 24c111b114b..6db5fb6ef40 100644
--- a/ports/geckolib/properties.mako.rs
+++ b/ports/geckolib/properties.mako.rs
@@ -44,6 +44,24 @@ pub struct GeckoComputedValues {
     pub root_font_size: Au,
 }
 
+impl GeckoComputedValues {
+    pub fn inherit_from(parent: &Arc<Self>) -> Arc<Self> {
+        Arc::new(GeckoComputedValues {
+            custom_properties: parent.custom_properties.clone(),
+            shareable: parent.shareable,
+            writing_mode: parent.writing_mode,
+            root_font_size: parent.root_font_size,
+            % for style_struct in data.style_structs:
+            % if style_struct.inherited:
+            ${style_struct.ident}: parent.${style_struct.ident}.clone(),
+            % else:
+            ${style_struct.ident}: Self::initial_values().${style_struct.ident}.clone(),
+            % endif
+            % endfor
+        })
+    }
+}
+
 impl ComputedValues for GeckoComputedValues {
 % for style_struct in data.style_structs:
     type Concrete${style_struct.trait_name} = ${style_struct.gecko_struct_name};
@@ -76,19 +94,7 @@ impl ComputedValues for GeckoComputedValues {
         // Gecko expects text nodes to be styled as if they were elements that
         // matched no rules (that is, inherited style structs are inherited and
         // non-inherited style structs are set to their initial values).
-        Arc::new(GeckoComputedValues {
-            custom_properties: parent.custom_properties.clone(),
-            shareable: parent.shareable,
-            writing_mode: parent.writing_mode,
-            root_font_size: parent.root_font_size,
-            % for style_struct in data.style_structs:
-            % if style_struct.inherited:
-            ${style_struct.ident}: parent.${style_struct.ident}.clone(),
-            % else:
-            ${style_struct.ident}: Self::initial_values().${style_struct.ident}.clone(),
-            % endif
-            % endfor
-        })
+        GeckoComputedValues::inherit_from(parent)
     }
 
     fn initial_values() -> &'static Self { &*INITIAL_GECKO_VALUES }