Auto merge of #15576 - mbrubeck:align, r=Manishearth

stylo: Implement 'align-self' and 'justify-self'

Stylo-only patch to match Gecko property support. Part of #15001. r? @Manishearth

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5 files changed, 124 insertions, 11 deletions

diff --git a/components/style/properties/gecko.mako.rs b/components/style/properties/gecko.mako.rs
index 822646bae7e..722faf11326 100644
--- a/components/style/properties/gecko.mako.rs
+++ b/components/style/properties/gecko.mako.rs
@@ -864,7 +864,7 @@ fn static_assert() {
 <% skip_position_longhands = " ".join(x.ident for x in SIDES + GRID_LINES) %>
 <%self:impl_trait style_struct_name="Position"
                   skip_longhands="${skip_position_longhands} z-index box-sizing order align-content
-                                  justify-content">
+                                  justify-content align-self justify-self">
     % for side in SIDES:
     <% impl_split_style_coord("%s" % side.ident,
                               "mOffset",
@@ -914,6 +914,18 @@ fn static_assert() {
 
     ${impl_simple_copy('justify_content', 'mJustifyContent')}
 
+    pub fn set_align_self(&mut self, v: longhands::align_self::computed_value::T) {
+        self.gecko.mAlignSelf = v.0.bits()
+    }
+
+    ${impl_simple_copy('align_self', 'mAlignSelf')}
+
+    pub fn set_justify_self(&mut self, v: longhands::justify_self::computed_value::T) {
+        self.gecko.mJustifySelf = v.0.bits()
+    }
+
+    ${impl_simple_copy('justify_self', 'mJustifySelf')}
+
     pub fn set_box_sizing(&mut self, v: longhands::box_sizing::computed_value::T) {
         use computed_values::box_sizing::T;
         use gecko_bindings::structs::StyleBoxSizing;
diff --git a/components/style/properties/longhand/position.mako.rs b/components/style/properties/longhand/position.mako.rs
index 59edcd92672..b169f74c396 100644
--- a/components/style/properties/longhand/position.mako.rs
+++ b/components/style/properties/longhand/position.mako.rs
@@ -140,14 +140,27 @@ ${helpers.predefined_type("flex-shrink", "Number",
                           animatable=True)}
 
 // https://drafts.csswg.org/css-align/#align-self-property
-// FIXME: We don't support the Gecko value 'normal' yet.
-${helpers.single_keyword("align-self", "auto stretch flex-start flex-end center baseline",
-                         need_clone=True,
-                         extra_prefixes="webkit",
-                         extra_gecko_values="normal",
-                         gecko_constant_prefix="NS_STYLE_ALIGN",
-                         spec="https://drafts.csswg.org/css-flexbox/#propdef-align-self",
-                         animatable=False)}
+% if product == "servo":
+    // FIXME: Update Servo to support the same syntax as Gecko.
+    ${helpers.single_keyword("align-self", "auto stretch flex-start flex-end center baseline",
+                             need_clone=True,
+                             extra_prefixes="webkit",
+                             spec="https://drafts.csswg.org/css-flexbox/#propdef-align-self",
+                             animatable=False)}
+% else:
+    ${helpers.predefined_type(name="align-self",
+                              type="AlignJustifySelf",
+                              initial_value="specified::AlignJustifySelf::auto()",
+                              spec="https://drafts.csswg.org/css-align/#align-self-property",
+                              extra_prefixes="webkit",
+                              animatable=False)}
+
+    ${helpers.predefined_type(name="justify-self",
+                              type="AlignJustifySelf",
+                              initial_value="specified::AlignJustifySelf::auto()",
+                              spec="https://drafts.csswg.org/css-align/#justify-self-property",
+                              animatable=False)}
+% endif
 
 // https://drafts.csswg.org/css-flexbox/#propdef-order
 <%helpers:longhand name="order" animatable="True" extra_prefixes="webkit"
diff --git a/components/style/values/computed/mod.rs b/components/style/values/computed/mod.rs
index b648e50c3c5..3c22ab1a8bb 100644
--- a/components/style/values/computed/mod.rs
+++ b/components/style/values/computed/mod.rs
@@ -17,7 +17,7 @@ pub use self::image::{AngleOrCorner, EndingShape as GradientShape, Gradient, Gra
 pub use self::image::{LengthOrKeyword, LengthOrPercentageOrKeyword};
 pub use super::{Auto, Either, None_};
 #[cfg(feature = "gecko")]
-pub use super::specified::AlignJustifyContent;
+pub use super::specified::{AlignJustifyContent, AlignJustifySelf};
 pub use super::specified::{Angle, BorderStyle, GridLine, Time, UrlOrNone};
 pub use super::specified::url::UrlExtraData;
 pub use self::length::{CalcLengthOrPercentage, Length, LengthOrNumber, LengthOrPercentage, LengthOrPercentageOrAuto};
@@ -124,6 +124,8 @@ impl ToComputedValue for specified::CSSColor {
 
 #[cfg(feature = "gecko")]
 impl ComputedValueAsSpecified for specified::AlignJustifyContent {}
+#[cfg(feature = "gecko")]
+impl ComputedValueAsSpecified for specified::AlignJustifySelf {}
 impl ComputedValueAsSpecified for specified::BorderStyle {}
 
 #[derive(Debug, PartialEq, Clone, Copy)]
diff --git a/components/style/values/specified/align.rs b/components/style/values/specified/align.rs
index fe7c779552b..26291f219e6 100644
--- a/components/style/values/specified/align.rs
+++ b/components/style/values/specified/align.rs
@@ -200,6 +200,57 @@ impl Parse for AlignJustifyContent {
     }
 }
 
+/// Value of the `align-self` or `justify-self` property.
+///
+/// https://drafts.csswg.org/css-align/#self-alignment
+#[derive(Copy, Clone, Debug, Eq, PartialEq)]
+pub struct AlignJustifySelf(pub AlignFlags);
+
+impl AlignJustifySelf {
+    /// The initial value 'auto'
+    #[inline]
+    pub fn auto() -> Self {
+        AlignJustifySelf(ALIGN_AUTO)
+    }
+}
+
+no_viewport_percentage!(AlignJustifySelf);
+
+impl ToCss for AlignJustifySelf {
+    fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
+        self.0.to_css(dest)
+    }
+}
+
+impl Parse for AlignJustifySelf {
+    // auto | normal | stretch | <baseline-position> |
+    // [ <overflow-position>? && <self-position> ]
+    fn parse(_: &ParserContext, input: &mut Parser) -> Result<Self, ()> {
+        // auto | normal | stretch | <baseline-position>
+        if let Ok(value) = input.try(parse_auto_normal_stretch_baseline) {
+            return Ok(AlignJustifySelf(value))
+        }
+        // [ <overflow-position>? && <self-position> ]
+        if let Ok(value) = input.try(parse_overflow_self_position) {
+            return Ok(AlignJustifySelf(value))
+        }
+        Err(())
+    }
+}
+
+
+// auto | normal | stretch | <baseline-position>
+fn parse_auto_normal_stretch_baseline(input: &mut Parser) -> Result<AlignFlags, ()> {
+    let ident = input.expect_ident()?;
+    match_ignore_ascii_case! { ident,
+        "auto" => Ok(ALIGN_AUTO),
+        "normal" => Ok(ALIGN_NORMAL),
+        "stretch" => Ok(ALIGN_STRETCH),
+        "baseline" => Ok(ALIGN_BASELINE),
+        _ => Err(())
+    }
+}
+
 // normal | <baseline-position>
 fn parse_normal_or_baseline(input: &mut Parser) -> Result<AlignFlags, ()> {
     let ident = input.expect_ident()?;
@@ -264,3 +315,38 @@ fn parse_overflow_position(input: &mut Parser) -> Result<AlignFlags, ()> {
         _ => Err(())
     }
 }
+
+// [ <overflow-position>? && <self-position> ]
+fn parse_overflow_self_position(input: &mut Parser) -> Result<AlignFlags, ()> {
+    // <self-position> followed by optional <overflow-position>
+    if let Ok(mut self_position) = input.try(|input| parse_self_position(input)) {
+        if let Ok(overflow) = input.try(|input| parse_overflow_position(input)) {
+            self_position |= overflow;
+        }
+        return Ok(self_position)
+    }
+    // <overflow-position> followed by required <self-position>
+    if let Ok(overflow) = input.try(|input| parse_overflow_position(input)) {
+        if let Ok(self_position) = input.try(|input| parse_self_position(input)) {
+            return Ok(overflow | self_position)
+        }
+    }
+    return Err(())
+}
+
+// <self-position>
+fn parse_self_position(input: &mut Parser) -> Result<AlignFlags, ()> {
+    let ident = input.expect_ident()?;
+    match_ignore_ascii_case! { ident,
+        "start" => Ok(ALIGN_START),
+        "end" => Ok(ALIGN_END),
+        "flex-start" => Ok(ALIGN_FLEX_START),
+        "flex-end" => Ok(ALIGN_FLEX_END),
+        "center" => Ok(ALIGN_CENTER),
+        "left" => Ok(ALIGN_LEFT),
+        "right" => Ok(ALIGN_RIGHT),
+        "self-start" => Ok(ALIGN_SELF_START),
+        "self-end" => Ok(ALIGN_SELF_END),
+        _ => Err(())
+    }
+}
diff --git a/components/style/values/specified/mod.rs b/components/style/values/specified/mod.rs
index b9f645e669e..e79d68b7777 100644
--- a/components/style/values/specified/mod.rs
+++ b/components/style/values/specified/mod.rs
@@ -21,7 +21,7 @@ use super::computed::{ComputedValueAsSpecified, Context, ToComputedValue};
 use super::computed::Shadow as ComputedShadow;
 
 #[cfg(feature = "gecko")]
-pub use self::align::AlignJustifyContent;
+pub use self::align::{AlignJustifyContent, AlignJustifySelf};
 pub use self::grid::GridLine;
 pub use self::image::{AngleOrCorner, ColorStop, EndingShape as GradientEndingShape, Gradient};
 pub use self::image::{GradientKind, HorizontalDirection, Image, LengthOrKeyword, LengthOrPercentageOrKeyword};