style: Add check for non-Copy specified value to ensure specified_is_copy always returns the right result.

Differential Revision: https://phabricator.services.mozilla.com/D2931

components/style/properties/data.py

@@ -290,14 +290,22 @@ class Longhand(object):
                 "AlignContent",
                 "AlignItems",
                 "AlignSelf",
+                "Appearance",
                 "BackgroundRepeat",
                 "BorderImageRepeat",
                 "BorderStyle",
+                "Clear",
                 "ColumnCount",
                 "Contain",
+                "Display",
+                "Float",
+                "FontSizeAdjust",
+                "FontStretch",
+                "FontStyle",
                 "FontStyleAdjust",
                 "FontSynthesis",
                 "FontWeight",
+                "GreaterThanOrEqualToOneNumber",
                 "GridAutoFlow",
                 "InitialLetter",
                 "Integer",
@@ -311,10 +319,13 @@ class Longhand(object):
                 "NonNegativeNumber",
                 "Opacity",
                 "OutlineStyle",
+                "OverflowClipBox",
                 "OverscrollBehavior",
                 "Percentage",
+                "SVGOpacity",
                 "SVGPaintOrder",
                 "ScrollSnapType",
+                "TextAlign",
                 "TextDecorationLine",
                 "TouchAction",
                 "TransformStyle",
@@ -322,6 +333,8 @@ class Longhand(object):
                 "XTextZoom",
                 "ZIndex",
             }
+        if self.name == "overflow-y":
+            return True
         return bool(self.keyword)
 
     def animated_type(self):

components/style/properties/longhands/box.mako.rs

@@ -448,7 +448,7 @@ ${helpers.predefined_type(
 
 ${helpers.predefined_type(
     "perspective-origin",
-    "position::Position",
+    "Position",
     "computed::position::Position::center()",
     boxed=True,
     extra_prefixes=transform_extra_prefixes,

components/style/properties/properties.mako.rs

@@ -305,6 +305,21 @@ impl Clone for PropertyDeclaration {
             }
         }
 
+        // This function ensures that all properties not handled above
+        // do not have a specified value implements Copy. If you hit
+        // compile error here, you may want to add the type name into
+        // Longhand.specified_is_copy in data.py.
+        fn _static_assert_others_are_not_copy() {
+            struct Helper<T>(T);
+            trait AssertCopy { fn assert() {} }
+            trait AssertNotCopy { fn assert() {} }
+            impl<T: Copy> AssertCopy for Helper<T> {}
+            % for ty in set(x["type"] for x in others):
+            impl AssertNotCopy for Helper<${ty}> {}
+            Helper::<${ty}>::assert();
+            % endfor
+        }
+
         match *self {
             ${" |\n".join("{}(..)".format(v["name"]) for v in copy)} => {
                 unsafe { debug_unreachable!() }