Auto merge of #19497 - emilio:overflow-clip-box, r=emilio,nox

style: Add internal overflow-clip-box-block/-inline properties and make overflow-clip-box a shorthand.

These are the changes from bug 1422839. First commit is reviewed by me, the second is a fixup to that.

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components/style/properties/gecko.mako.rs

@@ -3098,6 +3098,7 @@ fn static_assert() {
                           scroll-snap-type-x scroll-snap-type-y scroll-snap-coordinate
                           perspective-origin -moz-binding will-change
                           overscroll-behavior-x overscroll-behavior-y
+                          overflow-clip-box-inline overflow-clip-box-block
                           perspective-origin -moz-binding will-change
                           shape-outside contain touch-action""" %>
 <%self:impl_trait style_struct_name="Box" skip_longhands="${skip_box_longhands}">
@@ -3491,6 +3492,10 @@ fn static_assert() {
     ${impl_keyword('overscroll_behavior_x', 'mOverscrollBehaviorX', overscroll_behavior_keyword)}
     ${impl_keyword('overscroll_behavior_y', 'mOverscrollBehaviorY', overscroll_behavior_keyword)}
 
+    <% overflow_clip_box_keyword = Keyword("overflow-clip-box", "padding-box content-box") %>
+    ${impl_keyword('overflow_clip_box_inline', 'mOverflowClipBoxInline', overflow_clip_box_keyword)}
+    ${impl_keyword('overflow_clip_box_block', 'mOverflowClipBoxBlock', overflow_clip_box_keyword)}
+
     pub fn set_perspective_origin(&mut self, v: longhands::perspective_origin::computed_value::T) {
         self.gecko.mPerspectiveOrigin[0].set(v.horizontal);
         self.gecko.mPerspectiveOrigin[1].set(v.vertical);

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

@@ -373,12 +373,21 @@ ${helpers.single_keyword("-servo-overflow-clip-box", "padding-box content-box",
     spec="Internal, not web-exposed, \
           may be standardized in the future (https://developer.mozilla.org/en-US/docs/Web/CSS/overflow-clip-box)")}
 
-${helpers.single_keyword("overflow-clip-box", "padding-box content-box",
+% for direction in ["inline", "block"]:
-    products="gecko", animation_value_type="discrete", enabled_in="ua",
+    ${helpers.predefined_type(
-    gecko_pref="layout.css.overflow-clip-box.enabled",
+        "overflow-clip-box-" + direction,
-    flags="APPLIES_TO_PLACEHOLDER",
+        "OverflowClipBox",
-    spec="Internal, not web-exposed, \
+        "computed::OverflowClipBox::padding_box",
-          may be standardized in the future (https://developer.mozilla.org/en-US/docs/Web/CSS/overflow-clip-box)")}
+        products="gecko",
+        enabled_in="ua",
+        needs_context=False,
+        flags="APPLIES_TO_PLACEHOLDER",
+        gecko_pref="layout.css.overscroll-behavior.enabled",
+        animation_value_type="discrete",
+        spec="Internal, may be standardized in the future: \
+              https://developer.mozilla.org/en-US/docs/Web/CSS/overflow-clip-box",
+    )}
+% endfor
 
 <%
     overflow_custom_consts = { "-moz-hidden-unscrollable": "CLIP" }

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

@@ -58,6 +58,44 @@
     }
 </%helpers:shorthand>
 
+<%helpers:shorthand
+    name="overflow-clip-box"
+    sub_properties="overflow-clip-box-block overflow-clip-box-inline"
+    enabled_in="ua"
+    gecko_pref="layout.css.overflow-clip-box.enabled"
+    spec="Internal, may be standardized in the future "
+         "(https://developer.mozilla.org/en-US/docs/Web/CSS/overflow-clip-box)"
+    products="gecko"
+>
+    use values::specified::OverflowClipBox;
+    pub fn parse_value<'i, 't>(
+        _: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
+        let block_value = OverflowClipBox::parse(input)?;
+        let inline_value =
+            input.try(|input| OverflowClipBox::parse(input)).unwrap_or(block_value);
+
+        Ok(expanded! {
+          overflow_clip_box_block: block_value,
+          overflow_clip_box_inline: inline_value,
+        })
+    }
+
+    impl<'a> ToCss for LonghandsToSerialize<'a>  {
+        fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
+            self.overflow_clip_box_block.to_css(dest)?;
+
+            if self.overflow_clip_box_block != self.overflow_clip_box_inline {
+                dest.write_str(" ")?;
+                self.overflow_clip_box_inline.to_css(dest)?;
+            }
+
+            Ok(())
+        }
+    }
+</%helpers:shorthand>
+
 macro_rules! try_parse_one {
     ($input: expr, $var: ident, $prop_module: ident) => {
         if $var.is_none() {

components/style/values/computed/box.rs

@@ -9,7 +9,7 @@ use values::computed::length::LengthOrPercentage;
 use values::generics::box_::AnimationIterationCount as GenericAnimationIterationCount;
 use values::generics::box_::VerticalAlign as GenericVerticalAlign;
 
-pub use values::specified::box_::{AnimationName, OverscrollBehavior, ScrollSnapType};
+pub use values::specified::box_::{AnimationName, OverflowClipBox, OverscrollBehavior, ScrollSnapType};
 
 /// A computed value for the `vertical-align` property.
 pub type VerticalAlign = GenericVerticalAlign<LengthOrPercentage>;

components/style/values/computed/mod.rs

@@ -40,7 +40,8 @@ pub use self::font::{FontSize, FontSizeAdjust, FontSynthesis, FontWeight, FontVa
 pub use self::font::{FontFamily, FontLanguageOverride, FontVariantSettings, FontVariantEastAsian};
 pub use self::font::{FontVariantLigatures, FontVariantNumeric, FontFeatureSettings};
 pub use self::font::{MozScriptLevel, MozScriptMinSize, MozScriptSizeMultiplier, XTextZoom, XLang};
-pub use self::box_::{AnimationIterationCount, AnimationName, OverscrollBehavior, ScrollSnapType, VerticalAlign};
+pub use self::box_::{AnimationIterationCount, AnimationName, OverscrollBehavior};
+pub use self::box_::{OverflowClipBox, ScrollSnapType, VerticalAlign};
 pub use self::color::{Color, ColorPropertyValue, RGBAColor};
 pub use self::effects::{BoxShadow, Filter, SimpleShadow};
 pub use self::flex::FlexBasis;

components/style/values/specified/box.rs

@@ -124,3 +124,10 @@ define_css_keyword_enum! { OverscrollBehavior:
     "none" => None,
 }
 add_impls_for_keyword_enum!(OverscrollBehavior);
+
+// FIXME(emilio): Make all keywords CamelCase.
+define_css_keyword_enum! { OverflowClipBox:
+    "padding-box" => padding_box,
+    "content-box" => content_box,
+}
+add_impls_for_keyword_enum!(OverflowClipBox);

components/style/values/specified/mod.rs

@@ -34,7 +34,8 @@ pub use self::font::{FontSize, FontSizeAdjust, FontSynthesis, FontWeight, FontVa
 pub use self::font::{FontFamily, FontLanguageOverride, FontVariantSettings, FontVariantEastAsian};
 pub use self::font::{FontVariantLigatures, FontVariantNumeric, FontFeatureSettings};
 pub use self::font::{MozScriptLevel, MozScriptMinSize, MozScriptSizeMultiplier, XTextZoom, XLang};
-pub use self::box_::{AnimationIterationCount, AnimationName, OverscrollBehavior, ScrollSnapType, VerticalAlign};
+pub use self::box_::{AnimationIterationCount, AnimationName, OverscrollBehavior};
+pub use self::box_::{OverflowClipBox, ScrollSnapType, VerticalAlign};
 pub use self::color::{Color, ColorPropertyValue, RGBAColor};
 pub use self::effects::{BoxShadow, Filter, SimpleShadow};
 pub use self::flex::FlexBasis;