Auto merge of #16488 - heycam:wm, r=Manishearth

style: add Gecko-only support for sideways-{lr,rl} and deprecated SVG 1.1 writing-mode values

From https://bugzilla.mozilla.org/show_bug.cgi?id=1356510.

<!-- Reviewable:start -->
---
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/16488)
<!-- Reviewable:end -->

components/style/logical_geometry.rs

@@ -29,8 +29,12 @@ bitflags!(
         const FLAG_RTL = 1 << 0,
         const FLAG_VERTICAL = 1 << 1,
         const FLAG_VERTICAL_LR = 1 << 2,
-        const FLAG_SIDEWAYS = 1 << 3,
-        const FLAG_UPRIGHT = 1 << 4,
+        /// For vertical writing modes only.  When set, line-over/line-under
+        /// sides are inverted from block-start/block-end.  This flag is
+        /// set when sideways-lr is used.
+        const FLAG_LINE_INVERTED = 1 << 3,
+        const FLAG_SIDEWAYS = 1 << 4,
+        const FLAG_UPRIGHT = 1 << 5,
     }
 );
 
@@ -50,7 +54,7 @@ impl WritingMode {
     #[inline]
     pub fn is_inline_tb(&self) -> bool {
         // https://drafts.csswg.org/css-writing-modes-3/#logical-to-physical
-        !self.intersects(FLAG_RTL)
+        self.intersects(FLAG_RTL) == self.intersects(FLAG_LINE_INVERTED)
     }
 
     #[inline]
@@ -145,6 +149,9 @@ impl fmt::Display for WritingMode {
             if self.intersects(FLAG_SIDEWAYS) {
                 try!(write!(formatter, " Sideways"));
             }
+            if self.intersects(FLAG_LINE_INVERTED) {
+                try!(write!(formatter, " Inverted"));
+            }
         } else {
             try!(write!(formatter, "H"));
         }

components/style/properties/data.py

@@ -33,10 +33,20 @@ def to_camel_case(ident):
     return re.sub("(^|_|-)([a-z])", lambda m: m.group(2).upper(), ident.strip("_").strip("-"))
 
 
+def parse_aliases(value):
+    aliases = {}
+    for pair in value.split():
+        [a, v] = pair.split("=")
+        aliases[a] = v
+    return aliases
+
+
 class Keyword(object):
     def __init__(self, name, values, gecko_constant_prefix=None,
                  gecko_enum_prefix=None, custom_consts=None,
                  extra_gecko_values=None, extra_servo_values=None,
+                 aliases=None,
+                 extra_gecko_aliases=None, extra_servo_aliases=None,
                  gecko_strip_moz_prefix=True,
                  gecko_inexhaustive=None):
         self.name = name
@@ -48,6 +58,9 @@ def __init__(self, name, values, gecko_constant_prefix=None,
         self.gecko_enum_prefix = gecko_enum_prefix
         self.extra_gecko_values = (extra_gecko_values or "").split()
         self.extra_servo_values = (extra_servo_values or "").split()
+        self.aliases = parse_aliases(aliases or "")
+        self.extra_gecko_aliases = parse_aliases(extra_gecko_aliases or "")
+        self.extra_servo_aliases = parse_aliases(extra_servo_aliases or "")
         self.consts_map = {} if custom_consts is None else custom_consts
         self.gecko_strip_moz_prefix = gecko_strip_moz_prefix
         self.gecko_inexhaustive = gecko_inexhaustive or (gecko_enum_prefix is None)
@@ -58,6 +71,16 @@ def gecko_values(self):
     def servo_values(self):
         return self.values + self.extra_servo_values
 
+    def gecko_aliases(self):
+        aliases = self.aliases.copy()
+        aliases.update(self.extra_gecko_aliases)
+        return aliases
+
+    def servo_aliases(self):
+        aliases = self.aliases.copy()
+        aliases.update(self.extra_servo_aliases)
+        return aliases
+
     def values_for(self, product):
         if product == "gecko":
             return self.gecko_values()
@@ -66,6 +89,14 @@ def values_for(self, product):
         else:
             raise Exception("Bad product: " + product)
 
+    def aliases_for(self, product):
+        if product == "gecko":
+            return self.gecko_aliases()
+        elif product == "servo":
+            return self.servo_aliases()
+        else:
+            raise Exception("Bad product: " + product)
+
     def gecko_constant(self, value):
         moz_stripped = value.replace("-moz-", '') if self.gecko_strip_moz_prefix else value.replace("-moz-", 'moz-')
         mapped = self.consts_map.get(value)

components/style/properties/helpers.mako.rs

@@ -395,9 +395,33 @@
 
 <%def name="single_keyword(name, values, vector=False, **kwargs)">
     <%call expr="single_keyword_computed(name, values, vector, **kwargs)">
-        use values::computed::ComputedValueAsSpecified;
+        % if not "extra_specified" in kwargs and ("aliases" in kwargs or (("extra_%s_aliases" % product) in kwargs)):
+            impl ToComputedValue for SpecifiedValue {
+                type ComputedValue = computed_value::T;
+
+                #[inline]
+                fn to_computed_value(&self, _context: &Context) -> computed_value::T {
+                    match *self {
+                        % for value in data.longhands_by_name[name].keyword.values_for(product):
+                            SpecifiedValue::${to_rust_ident(value)} => computed_value::T::${to_rust_ident(value)},
+                        % endfor
+                    }
+                }
+                #[inline]
+                fn from_computed_value(computed: &computed_value::T) -> Self {
+                    match *computed {
+                        % for value in data.longhands_by_name[name].keyword.values_for(product):
+                            computed_value::T::${to_rust_ident(value)} => SpecifiedValue::${to_rust_ident(value)},
+                        % endfor
+                    }
+                }
+            }
+        % else:
+            use values::computed::ComputedValueAsSpecified;
+            impl ComputedValueAsSpecified for SpecifiedValue {}
+        % endif
+
         use values::HasViewportPercentage;
-        impl ComputedValueAsSpecified for SpecifiedValue {}
         no_viewport_percentage!(SpecifiedValue);
     </%call>
 </%def>
@@ -444,17 +468,25 @@
         keyword_kwargs = {a: kwargs.pop(a, None) for a in [
             'gecko_constant_prefix', 'gecko_enum_prefix',
             'extra_gecko_values', 'extra_servo_values',
+            'aliases', 'extra_gecko_aliases', 'extra_servo_aliases',
             'custom_consts', 'gecko_inexhaustive',
         ]}
     %>
 
     <%def name="inner_body(keyword, extra_specified=None, needs_conversion=False)">
-        % if extra_specified:
+        % if extra_specified or keyword.aliases_for(product):
             use style_traits::ToCss;
             define_css_keyword_enum! { SpecifiedValue:
-                % for value in keyword.values_for(product) + extra_specified.split():
-                    "${value}" => ${to_rust_ident(value)},
-                % endfor
+                values {
+                    % for value in keyword.values_for(product) + (extra_specified or "").split():
+                        "${value}" => ${to_rust_ident(value)},
+                    % endfor
+                }
+                aliases {
+                    % for alias, value in keyword.aliases_for(product).iteritems():
+                        "${alias}" => ${to_rust_ident(value)},
+                    % endfor
+                }
             }
         % else:
             pub use self::computed_value::T as SpecifiedValue;
@@ -493,6 +525,7 @@
                 conversion_values = keyword.values_for(product)
                 if extra_specified:
                     conversion_values += extra_specified.split()
+                conversion_values += keyword.aliases_for(product).keys()
             %>
             ${gecko_keyword_conversion(keyword, values=conversion_values)}
         % endif

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

@@ -18,6 +18,10 @@ ${helpers.single_keyword("visibility",
 // https://drafts.csswg.org/css-writing-modes-3
 ${helpers.single_keyword("writing-mode",
                          "horizontal-tb vertical-rl vertical-lr",
+                         extra_gecko_values="sideways-rl sideways-lr",
+                         extra_gecko_aliases="lr=horizontal-tb lr-tb=horizontal-tb \
+                                              rl=horizontal-tb rl-tb=horizontal-tb \
+                                              tb=vertical-rl   tb-rl=vertical-rl",
                          experimental=True,
                          need_clone=True,
                          animation_type="none",
@@ -27,42 +31,13 @@ ${helpers.single_keyword("direction", "ltr rtl", need_clone=True, animation_type
                          spec="https://drafts.csswg.org/css-writing-modes/#propdef-direction",
                          needs_conversion=True)}
 
-<%helpers:single_keyword_computed
-    name="text-orientation"
-    values="mixed upright sideways"
-    extra_specified="sideways-right"
-    products="gecko"
-    need_clone="True"
-    animation_type="none"
-    spec="https://drafts.csswg.org/css-writing-modes/#propdef-text-orientation"
->
-    use values::HasViewportPercentage;
-    no_viewport_percentage!(SpecifiedValue);
-
-    impl ToComputedValue for SpecifiedValue {
-        type ComputedValue = computed_value::T;
-
-        #[inline]
-        fn to_computed_value(&self, _: &Context) -> computed_value::T {
-            match *self {
-                % for value in "mixed upright sideways".split():
-                    SpecifiedValue::${value} => computed_value::T::${value},
-                % endfor
-                // https://drafts.csswg.org/css-writing-modes-3/#valdef-text-orientation-sideways-right
-                SpecifiedValue::sideways_right => computed_value::T::sideways,
-            }
-        }
-
-        #[inline]
-        fn from_computed_value(computed: &computed_value::T) -> SpecifiedValue {
-            match *computed {
-                % for value in "mixed upright sideways".split():
-                    computed_value::T::${value} => SpecifiedValue::${value},
-                % endfor
-            }
-        }
-    }
-</%helpers:single_keyword_computed>
+${helpers.single_keyword("text-orientation",
+                         "mixed upright sideways",
+                         extra_gecko_aliases="sideways-right=sideways",
+                         products="gecko",
+                         need_clone=True,
+                         animation_type="none",
+                         spec="https://drafts.csswg.org/css-writing-modes/#propdef-text-orientation")}
 
 // CSS Color Module Level 4
 // https://drafts.csswg.org/css-color/

components/style/properties/properties.mako.rs

@@ -1936,16 +1936,33 @@ pub fn get_writing_mode(inheritedbox_style: &style_structs::InheritedBox) -> Wri
             flags.insert(logical_geometry::FLAG_VERTICAL);
             flags.insert(logical_geometry::FLAG_VERTICAL_LR);
         },
-    }
-    % if product == "gecko":
-    match inheritedbox_style.clone_text_orientation() {
-        computed_values::text_orientation::T::mixed => {},
-        computed_values::text_orientation::T::upright => {
-            flags.insert(logical_geometry::FLAG_UPRIGHT);
+        % if product == "gecko":
+        computed_values::writing_mode::T::sideways_rl => {
+            flags.insert(logical_geometry::FLAG_VERTICAL);
+            flags.insert(logical_geometry::FLAG_SIDEWAYS);
         },
-        computed_values::text_orientation::T::sideways => {
+        computed_values::writing_mode::T::sideways_lr => {
+            flags.insert(logical_geometry::FLAG_VERTICAL);
+            flags.insert(logical_geometry::FLAG_VERTICAL_LR);
+            flags.insert(logical_geometry::FLAG_LINE_INVERTED);
             flags.insert(logical_geometry::FLAG_SIDEWAYS);
         },
+        % endif
+    }
+    % if product == "gecko":
+    // If FLAG_SIDEWAYS is already set, this means writing-mode is either
+    // sideways-rl or sideways-lr, and for both of these values,
+    // text-orientation has no effect.
+    if !flags.intersects(logical_geometry::FLAG_SIDEWAYS) {
+        match inheritedbox_style.clone_text_orientation() {
+            computed_values::text_orientation::T::mixed => {},
+            computed_values::text_orientation::T::upright => {
+                flags.insert(logical_geometry::FLAG_UPRIGHT);
+            },
+            computed_values::text_orientation::T::sideways => {
+                flags.insert(logical_geometry::FLAG_SIDEWAYS);
+            },
+        }
     }
     % endif
     flags

components/style_traits/values.rs

@@ -82,37 +82,62 @@ impl_to_css_for_predefined_type!(::cssparser::UnicodeRange);
 
 #[macro_export]
 macro_rules! define_css_keyword_enum {
+    ($name: ident: values { $( $css: expr => $variant: ident),+, }
+                   aliases { $( $alias: expr => $alias_variant: ident ),+, }) => {
+        __define_css_keyword_enum__add_optional_traits!($name [ $( $css => $variant ),+ ]
+                                                              [ $( $alias => $alias_variant ),+ ]);
+    };
+    ($name: ident: values { $( $css: expr => $variant: ident),+, }
+                   aliases { $( $alias: expr => $alias_variant: ident ),* }) => {
+        __define_css_keyword_enum__add_optional_traits!($name [ $( $css => $variant ),+ ]
+                                                              [ $( $alias => $alias_variant ),* ]);
+    };
+    ($name: ident: values { $( $css: expr => $variant: ident),+ }
+                   aliases { $( $alias: expr => $alias_variant: ident ),+, }) => {
+        __define_css_keyword_enum__add_optional_traits!($name [ $( $css => $variant ),+ ]
+                                                              [ $( $alias => $alias_variant ),+ ]);
+    };
+    ($name: ident: values { $( $css: expr => $variant: ident),+ }
+                   aliases { $( $alias: expr => $alias_variant: ident ),* }) => {
+        __define_css_keyword_enum__add_optional_traits!($name [ $( $css => $variant ),+ ]
+                                                              [ $( $alias => $alias_variant ),* ]);
+    };
     ($name: ident: $( $css: expr => $variant: ident ),+,) => {
-        __define_css_keyword_enum__add_optional_traits!($name [ $( $css => $variant ),+ ]);
+        __define_css_keyword_enum__add_optional_traits!($name [ $( $css => $variant ),+ ] []);
     };
     ($name: ident: $( $css: expr => $variant: ident ),+) => {
-        __define_css_keyword_enum__add_optional_traits!($name [ $( $css => $variant ),+ ]);
+        __define_css_keyword_enum__add_optional_traits!($name [ $( $css => $variant ),+ ] []);
     };
 }
 
 #[cfg(feature = "servo")]
 #[macro_export]
 macro_rules! __define_css_keyword_enum__add_optional_traits {
-    ($name: ident [ $( $css: expr => $variant: ident ),+ ]) => {
+    ($name: ident [ $( $css: expr => $variant: ident ),+ ]
+                  [ $( $alias: expr => $alias_variant: ident),* ]) => {
         __define_css_keyword_enum__actual! {
-            $name [ Deserialize, Serialize, HeapSizeOf ] [ $( $css => $variant ),+ ]
+            $name [ Deserialize, Serialize, HeapSizeOf ]
+                  [ $( $css => $variant ),+ ]
+                  [ $( $alias => $alias_variant ),* ]
         }
     };
 }
 
 #[cfg(not(feature = "servo"))]
 #[macro_export]
 macro_rules! __define_css_keyword_enum__add_optional_traits {
-    ($name: ident [ $( $css: expr => $variant: ident ),+ ]) => {
+    ($name: ident [ $( $css: expr => $variant: ident ),+ ] [ $( $alias: expr => $alias_variant: ident),* ]) => {
         __define_css_keyword_enum__actual! {
-            $name [] [ $( $css => $variant ),+ ]
+            $name [] [ $( $css => $variant ),+ ] [ $( $alias => $alias_variant ),* ]
         }
     };
 }
 
 #[macro_export]
 macro_rules! __define_css_keyword_enum__actual {
-    ($name: ident [ $( $derived_trait: ident),* ] [ $( $css: expr => $variant: ident ),+ ]) => {
+    ($name: ident [ $( $derived_trait: ident),* ]
+                  [ $( $css: expr => $variant: ident ),+ ]
+                  [ $( $alias: expr => $alias_variant: ident ),* ]) => {
         #[allow(non_camel_case_types, missing_docs)]
         #[derive(Clone, Copy, Debug, Eq, Hash, PartialEq $(, $derived_trait )* )]
         pub enum $name {
@@ -130,6 +155,7 @@ macro_rules! __define_css_keyword_enum__actual {
             pub fn from_ident(ident: &str) -> Result<$name, ()> {
                 match_ignore_ascii_case! { ident,
                                            $( $css => Ok($name::$variant), )+
+                                           $( $alias => Ok($name::$alias_variant), )*
                                            _ => Err(())
                 }
             }