style: Implement 'inline list-item' and 'inline flow-root list-item' values for the 'display' property.

Differential Revision: https://phabricator.services.mozilla.com/D39832

components/style/style_adjuster.rs

@@ -8,6 +8,8 @@
 use crate::dom::TElement;
 use crate::properties::computed_value_flags::ComputedValueFlags;
 use crate::properties::longhands::display::computed_value::T as Display;
+#[cfg(feature = "gecko")]
+use crate::values::specified::box_::DisplayInside;
 use crate::properties::longhands::float::computed_value::T as Float;
 use crate::properties::longhands::overflow_x::computed_value::T as Overflow;
 use crate::properties::longhands::position::computed_value::T as Position;
@@ -175,7 +177,9 @@ impl<'a, 'b: 'a> StyleAdjuster<'a, 'b> {
     /// Apply the blockification rules based on the table in CSS 2.2 section 9.7.
     /// <https://drafts.csswg.org/css2/visuren.html#dis-pos-flo>
     /// A ::marker pseudo-element with 'list-style-position:outside' needs to
-    /// have its 'display' blockified.
+    /// have its 'display' blockified, unless the ::marker is for an inline
+    /// list-item (for which 'list-style-position:outside' behaves as 'inside').
+    /// https://drafts.csswg.org/css-lists-3/#list-style-position-property
     fn blockify_if_necessary<E>(&mut self, layout_parent_style: &ComputedValues, element: Option<E>)
     where
         E: TElement,
@@ -194,21 +198,19 @@ impl<'a, 'b: 'a> StyleAdjuster<'a, 'b> {
         let is_root = self.style.pseudo.is_none() && element.map_or(false, |e| e.is_root());
         blockify_if!(is_root);
         if !self.skip_item_display_fixup(element) {
-            blockify_if!(layout_parent_style
+            let parent_display = layout_parent_style.get_box().clone_display();
-                .get_box()
+            blockify_if!(parent_display.is_item_container());
-                .clone_display()
-                .is_item_container());
         }
 
         let is_item_or_root = blockify;
 
         blockify_if!(self.style.floated());
         blockify_if!(self.style.out_of_flow_positioned());
+        #[cfg(feature = "gecko")]
         blockify_if!(
             self.style.pseudo.map_or(false, |p| p.is_marker()) &&
-                self.style.get_parent_list().clone_list_style_position() ==
+             self.style.get_parent_list().clone_list_style_position() == ListStylePosition::Outside &&
-                    ListStylePosition::Outside
+             layout_parent_style.get_box().clone_display().inside() != DisplayInside::Inline);
-        );
 
         if !blockify {
             return;

components/style/values/specified/box.rs

@@ -393,55 +393,66 @@ impl Display {
 
     /// Convert this display into an equivalent block display.
     ///
-    /// Also used for style adjustments.
+    /// Also used for :root style adjustments.
     pub fn equivalent_block_display(&self, _is_root_element: bool) -> Self {
+        #[cfg(feature = "gecko")]
+        {
+            // Special handling for `contents` and `list-item`s on the root element.
+            if _is_root_element && (*self == Display::Contents || self.is_list_item()) {
+                return Display::Block;
+            }
+            match self.outside() {
+                DisplayOutside::Inline => {
+                    let inside =  match self.inside() {
+                        DisplayInside::Inline | DisplayInside::FlowRoot => DisplayInside::Block,
+                        // FIXME: we don't handle `block ruby` in layout yet, remove this when we do:
+                        DisplayInside::Ruby => DisplayInside::Block,
+                        inside => inside,
+                    };
+                    Display::from3(DisplayOutside::Block, inside, self.is_list_item())
+                },
+                DisplayOutside::Block | DisplayOutside::None => *self,
+                _ => Display::Block,
+            }
+        }
+        #[cfg(not(feature = "gecko"))]
         match *self {
             // Values that have a corresponding block-outside version.
-            #[cfg(any(feature = "gecko", feature = "servo-layout-2013"))]
+            #[cfg(feature = "servo-layout-2013")]
             Display::InlineTable => Display::Table,
-            #[cfg(any(feature = "gecko", feature = "servo-layout-2013"))]
+            #[cfg(feature = "servo-layout-2013")]
             Display::InlineFlex => Display::Flex,
 
-            #[cfg(feature = "gecko")]
-            Display::InlineGrid => Display::Grid,
-            #[cfg(feature = "gecko")]
-            Display::WebkitInlineBox => Display::WebkitBox,
-
-            // Special handling for contents and list-item on the root
-            // element for Gecko.
-            #[cfg(feature = "gecko")]
-            Display::Contents | Display::ListItem if _is_root_element => Display::Block,
-
             // These are not changed by blockification.
             Display::None | Display::Block => *self,
-            #[cfg(any(feature = "gecko", feature = "servo-layout-2013"))]
+            #[cfg(feature = "servo-layout-2013")]
             Display::Flex | Display::ListItem | Display::Table => *self,
 
-            #[cfg(feature = "gecko")]
-            Display::Contents | Display::FlowRoot | Display::Grid | Display::WebkitBox => *self,
-
             // Everything else becomes block.
             _ => Display::Block,
         }
     }
 
-    /// Convert this display into an inline-outside display.
+    /// Convert this display into an equivalent inline-outside display.
-    ///
+    /// https://drafts.csswg.org/css-display/#inlinify
-    /// Ideally it should implement spec: https://drafts.csswg.org/css-display/#inlinify
-    /// but the spec isn't stable enough, so we copy what Gecko does for now.
     #[cfg(feature = "gecko")]
     pub fn inlinify(&self) -> Self {
-        match *self {
+        match self.outside() {
-            Display::Block | Display::FlowRoot => Display::InlineBlock,
+            DisplayOutside::Block => {
-            Display::Table => Display::InlineTable,
+                let inside = match self.inside() {
-            Display::Flex => Display::InlineFlex,
+                    DisplayInside::Block => DisplayInside::FlowRoot,
-            Display::Grid => Display::InlineGrid,
+                    inside => inside,
-            // XXX bug 1105868 this should probably be InlineListItem:
+                };
-            Display::ListItem => Display::Inline,
+                Display::from3(DisplayOutside::Inline, inside, self.is_list_item())
-            Display::MozBox => Display::MozInlineBox,
+            },
-            Display::MozStack => Display::MozInlineStack,
+            DisplayOutside::XUL => {
-            Display::WebkitBox => Display::WebkitInlineBox,
+                match self.inside() {
-            other => other,
+                    DisplayInside::MozBox => Display::MozInlineBox,
+                    DisplayInside::MozStack => Display::MozInlineStack,
+                    _ => *self,
+                }
+            },
+            _ => *self,
         }
     }
 
@@ -496,8 +507,15 @@ impl ToCss for Display {
                 }
                 (_, inside) => {
                     if self.is_list_item() {
-                        debug_assert_eq!(inside, DisplayInside::FlowRoot);
+                        if outside != DisplayOutside::Block {
-                        dest.write_str("flow-root list-item")
+                            outside.to_css(dest)?;
+                            dest.write_str(" ")?;
+                        }
+                        if inside != DisplayInside::Flow {
+                            inside.to_css(dest)?;
+                            dest.write_str(" ")?;
+                        }
+                        dest.write_str("list-item")
                     } else {
                         inside.to_css(dest)
                     }
@@ -547,35 +565,10 @@ fn parse_display_outside<'i, 't>(
     Ok(try_match_ident_ignore_ascii_case! { input,
         "block" => DisplayOutside::Block,
         "inline" => DisplayOutside::Inline,
-        // FIXME: not supported in layout yet:
-        //"run-in" => DisplayOutside::RunIn,
-    })
-}
-
-/// FIXME: this can be replaced with parse_display_outside once we
-/// support all its values for list items.
-#[cfg(feature = "gecko")]
-fn parse_display_outside_for_list_item<'i, 't>(
-    input: &mut Parser<'i, 't>,
-) -> Result<DisplayOutside, ParseError<'i>> {
-    Ok(try_match_ident_ignore_ascii_case! { input,
-        "block" => DisplayOutside::Block,
-        // FIXME(bug 1105868): not supported in layout yet:
-        //"inline" => DisplayOutside::Inline,
         // FIXME(bug 2056): not supported in layout yet:
         //"run-in" => DisplayOutside::RunIn,
     })
 }
-/// Test a <display-outside> Result for same values as above.
-#[cfg(feature = "gecko")]
-fn is_valid_outside_for_list_item<'i>(
-    outside: &Result<DisplayOutside, ParseError<'i>>,
-) -> bool {
-    match outside {
-        Ok(DisplayOutside::Block) => true,
-        _ => false,
-    }
-}
 
 /// FIXME: this can be replaced with parse_display_outside once we
 /// support all its values for `ruby`.
@@ -637,18 +630,16 @@ impl Parse for Display {
         if !got_list_item && is_valid_inside_for_list_item(&inside) {
             got_list_item = input.try(parse_list_item).is_ok();
         }
-        let outside = if got_list_item {
+        let outside = match inside {
-            input.try(parse_display_outside_for_list_item)
+            // FIXME we don't handle `block ruby` in layout yet.
-        } else {
-            match inside {
             Ok(DisplayInside::Ruby) => input.try(parse_display_outside_for_ruby),
             _ => input.try(parse_display_outside),
-            }
         };
-        if !got_list_item && is_valid_outside_for_list_item(&outside) {
+        if outside.is_ok() {
+            if !got_list_item && (inside.is_err() || is_valid_inside_for_list_item(&inside)) {
                 got_list_item = input.try(parse_list_item).is_ok();
             }
-        if outside.is_ok() && inside.is_err(){
+            if inside.is_err() {
                 inside = if got_list_item {
                     input.try(parse_display_inside_for_list_item)
                 } else {
@@ -658,12 +649,11 @@ impl Parse for Display {
                         _ => input.try(parse_display_inside),
                     }
                 };
-            if !got_list_item &&
+                if !got_list_item && is_valid_inside_for_list_item(&inside) {
-                is_valid_outside_for_list_item(&outside) &&
-                is_valid_inside_for_list_item(&inside) {
                     got_list_item = input.try(parse_list_item).is_ok();
                 }
             }
+        }
         if got_list_item || inside.is_ok() || outside.is_ok() {
             let inside = inside.unwrap_or(DisplayInside::Flow);
             let outside = outside.unwrap_or(
@@ -730,6 +720,8 @@ impl SpecifiedValueInfo for Display {
           "inline-flex",
           "inline-grid",
           "inline-table",
+          "inline list-item",
+          "inline flow-root list-item",
           "list-item",
           "none",
           "ruby",