Auto merge of #20501 - emilio:parsing-style, r=nox

style: Use a more consistent style for parsing functions.

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14 files changed, 126 insertions, 69 deletions

diff --git a/components/style/properties/longhand/svg.mako.rs b/components/style/properties/longhand/svg.mako.rs
index 691b6870421..bea30301eb2 100644
--- a/components/style/properties/longhand/svg.mako.rs
+++ b/components/style/properties/longhand/svg.mako.rs
@@ -139,8 +139,10 @@ ${helpers.single_keyword("mask-origin",
         background_size::get_initial_value()
     }
 
-    pub fn parse<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                         -> Result<SpecifiedValue,ParseError<'i>> {
+    pub fn parse<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<SpecifiedValue, ParseError<'i>> {
         background_size::parse(context, input)
     }
 </%helpers:longhand>
diff --git a/components/style/properties/shorthand/background.mako.rs b/components/style/properties/shorthand/background.mako.rs
index 8fd2101ecec..b16c9918a24 100644
--- a/components/style/properties/shorthand/background.mako.rs
+++ b/components/style/properties/shorthand/background.mako.rs
@@ -33,8 +33,10 @@
         }
     }
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         let mut background_color = None;
 
         % for name in "image position_x position_y repeat size attachment origin clip".split():
@@ -200,8 +202,10 @@
     use values::specified::AllowQuirks;
     use values::specified::position::Position;
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         // Vec grows from 0 to 4 by default on first push().  So allocate with
         // capacity 1, so in the common case of only one item we don't way
         // overallocate.  Note that we always push at least one item if parsing
diff --git a/components/style/properties/shorthand/border.mako.rs b/components/style/properties/shorthand/border.mako.rs
index ec462510bf7..da3f8abbf33 100644
--- a/components/style/properties/shorthand/border.mako.rs
+++ b/components/style/properties/shorthand/border.mako.rs
@@ -24,8 +24,10 @@ ${helpers.four_sides_shorthand(
     use values::generics::rect::Rect;
     use values::specified::{AllowQuirks, BorderSideWidth};
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         let rect = Rect::parse_with(context, input, |_, i| {
             BorderSideWidth::parse_quirky(context, i, AllowQuirks::Yes)
         })?;
@@ -48,10 +50,10 @@ ${helpers.four_sides_shorthand(
 </%helpers:shorthand>
 
 
-pub fn parse_border<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                            -> Result<(specified::Color,
-                                       specified::BorderStyle,
-                                       specified::BorderSideWidth), ParseError<'i>> {
+pub fn parse_border<'i, 't>(
+    context: &ParserContext,
+    input: &mut Parser<'i, 't>,
+) -> Result<(specified::Color, specified::BorderStyle, specified::BorderSideWidth), ParseError<'i>> {
     use values::specified::{Color, BorderStyle, BorderSideWidth};
     let _unused = context;
     let mut color = None;
@@ -106,8 +108,10 @@ pub fn parse_border<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
         alias="${maybe_moz_logical_alias(product, (side, logical), '-moz-border-%s')}"
         spec="${spec}">
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         let (color, style, width) = super::parse_border(context, input)?;
         Ok(expanded! {
             border_${to_rust_ident(side)}_color: color,
@@ -138,8 +142,10 @@ pub fn parse_border<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
         for name in ['outset', 'repeat', 'slice', 'source', 'width'])}"
     spec="https://drafts.csswg.org/css-backgrounds/#border">
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         use properties::longhands::{border_image_outset, border_image_repeat, border_image_slice};
         use properties::longhands::{border_image_source, border_image_width};
 
@@ -207,8 +213,10 @@ pub fn parse_border<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
     use values::specified::border::BorderRadius;
     use parser::Parse;
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         let radii = BorderRadius::parse(context, input)?;
         Ok(expanded! {
             border_top_left_radius: radii.top_left,
@@ -242,8 +250,10 @@ pub fn parse_border<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
     use properties::longhands::{border_image_outset, border_image_repeat, border_image_slice};
     use properties::longhands::{border_image_source, border_image_width};
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         % for name in "outset repeat slice source width".split():
             let mut border_image_${name} = border_image_${name}::get_initial_specified_value();
         % endfor
diff --git a/components/style/properties/shorthand/box.mako.rs b/components/style/properties/shorthand/box.mako.rs
index e9c87dca6aa..7f2fe128eb2 100644
--- a/components/style/properties/shorthand/box.mako.rs
+++ b/components/style/properties/shorthand/box.mako.rs
@@ -11,8 +11,10 @@
         use properties::longhands::overflow_x::SpecifiedValue;
     % endif
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         % if product == "gecko":
             let moz_kw_found = input.try(|input| {
                 try_match_ident_ignore_ascii_case! { input,
@@ -118,8 +120,10 @@ macro_rules! try_parse_one {
     use properties::longhands::transition_${prop};
     % endfor
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         struct SingleTransition {
             % for prop in "duration timing_function delay".split():
             transition_${prop}: transition_${prop}::SingleSpecifiedValue,
@@ -129,8 +133,10 @@ macro_rules! try_parse_one {
             transition_property: Option<transition_property::SingleSpecifiedValue>,
         }
 
-        fn parse_one_transition<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                                        -> Result<SingleTransition,ParseError<'i>> {
+        fn parse_one_transition<'i, 't>(
+            context: &ParserContext,
+            input: &mut Parser<'i, 't>,
+        ) -> Result<SingleTransition,ParseError<'i>> {
             % for prop in "property duration timing_function delay".split():
             let mut ${prop} = None;
             % endfor
@@ -260,16 +266,20 @@ macro_rules! try_parse_one {
     use properties::longhands::animation_${prop};
     % endfor
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         struct SingleAnimation {
             % for prop in props:
             animation_${prop}: animation_${prop}::SingleSpecifiedValue,
             % endfor
         }
 
-        fn parse_one_animation<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                                       -> Result<SingleAnimation,ParseError<'i>> {
+        fn parse_one_animation<'i, 't>(
+            context: &ParserContext,
+            input: &mut Parser<'i, 't>,
+        ) -> Result<SingleAnimation, ParseError<'i>> {
             % for prop in props:
             let mut ${prop} = None;
             % endfor
@@ -364,8 +374,10 @@ macro_rules! try_parse_one {
                     spec="https://drafts.csswg.org/css-scroll-snap/#propdef-scroll-snap-type">
     use properties::longhands::scroll_snap_type_x;
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         let result = scroll_snap_type_x::parse(context, input)?;
         Ok(expanded! {
             scroll_snap_type_x: result,
diff --git a/components/style/properties/shorthand/column.mako.rs b/components/style/properties/shorthand/column.mako.rs
index a382850b672..cdd05dc786b 100644
--- a/components/style/properties/shorthand/column.mako.rs
+++ b/components/style/properties/shorthand/column.mako.rs
@@ -11,9 +11,10 @@
                     extra_prefixes="moz" spec="https://drafts.csswg.org/css-multicol/#propdef-columns">
     use properties::longhands::{column_count, column_width};
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
-
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         let mut column_count = None;
         let mut column_width = None;
         let mut autos = 0;
@@ -61,8 +62,10 @@
     use properties::longhands::{column_rule_width, column_rule_style};
     use properties::longhands::column_rule_color;
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         % for name in "width style color".split():
         let mut column_rule_${name} = None;
         % endfor
diff --git a/components/style/properties/shorthand/font.mako.rs b/components/style/properties/shorthand/font.mako.rs
index c2f8a09a6b0..cc3cd819cf2 100644
--- a/components/style/properties/shorthand/font.mako.rs
+++ b/components/style/properties/shorthand/font.mako.rs
@@ -42,8 +42,10 @@
     % endif
     use self::font_family::SpecifiedValue as FontFamily;
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         let mut nb_normals = 0;
         let mut style = None;
         let mut variant_caps = None;
@@ -262,8 +264,10 @@
     #[allow(unused_imports)]
     use values::specified::FontVariantLigatures;
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
     % for prop in sub_properties:
         let mut ${prop} = None;
     % endfor
diff --git a/components/style/properties/shorthand/inherited_svg.mako.rs b/components/style/properties/shorthand/inherited_svg.mako.rs
index 1742ef28ed7..0984e879369 100644
--- a/components/style/properties/shorthand/inherited_svg.mako.rs
+++ b/components/style/properties/shorthand/inherited_svg.mako.rs
@@ -9,8 +9,10 @@
     spec="https://www.w3.org/TR/SVG2/painting.html#MarkerShorthand">
     use values::specified::UrlOrNone;
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         use parser::Parse;
         let url = UrlOrNone::parse(context, input)?;
 
diff --git a/components/style/properties/shorthand/inherited_text.mako.rs b/components/style/properties/shorthand/inherited_text.mako.rs
index 95850f5c043..98ded998bb1 100644
--- a/components/style/properties/shorthand/inherited_text.mako.rs
+++ b/components/style/properties/shorthand/inherited_text.mako.rs
@@ -10,8 +10,10 @@
     spec="https://drafts.csswg.org/css-text-decor-3/#text-emphasis-property">
     use properties::longhands::{text_emphasis_color, text_emphasis_style};
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         let mut color = None;
         let mut style = None;
 
@@ -52,8 +54,10 @@
                     spec="https://compat.spec.whatwg.org/#the-webkit-text-stroke">
     use properties::longhands::{_webkit_text_stroke_color, _webkit_text_stroke_width};
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         let mut color = None;
         let mut width = None;
         loop {
diff --git a/components/style/properties/shorthand/list.mako.rs b/components/style/properties/shorthand/list.mako.rs
index 2468433e9b0..d7b723adf62 100644
--- a/components/style/properties/shorthand/list.mako.rs
+++ b/components/style/properties/shorthand/list.mako.rs
@@ -11,8 +11,10 @@
     use properties::longhands::{list_style_image, list_style_position, list_style_type};
     use values::{Either, None_};
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         // `none` is ambiguous until we've finished parsing the shorthands, so we count the number
         // of times we see it.
         let mut nones = 0u8;
diff --git a/components/style/properties/shorthand/mask.mako.rs b/components/style/properties/shorthand/mask.mako.rs
index 483ce9b50f8..d38eedb5854 100644
--- a/components/style/properties/shorthand/mask.mako.rs
+++ b/components/style/properties/shorthand/mask.mako.rs
@@ -36,8 +36,10 @@
         }
     }
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         % for name in "image mode position_x position_y size repeat origin clip composite".split():
             // Vec grows from 0 to 4 by default on first push().  So allocate
             // with capacity 1, so in the common case of only one item we don't
diff --git a/components/style/properties/shorthand/outline.mako.rs b/components/style/properties/shorthand/outline.mako.rs
index 95d6b0be28a..d2f04466629 100644
--- a/components/style/properties/shorthand/outline.mako.rs
+++ b/components/style/properties/shorthand/outline.mako.rs
@@ -12,8 +12,10 @@
     use values::specified;
     use parser::Parse;
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         let _unused = context;
         let mut color = None;
         let mut style = None;
@@ -64,8 +66,10 @@
     use values::specified::border::BorderRadius;
     use parser::Parse;
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         let radii = BorderRadius::parse(context, input)?;
         Ok(expanded! {
             _moz_outline_radius_topleft: radii.top_left,
diff --git a/components/style/properties/shorthand/position.mako.rs b/components/style/properties/shorthand/position.mako.rs
index 971f74ddb8f..2c58895c9d0 100644
--- a/components/style/properties/shorthand/position.mako.rs
+++ b/components/style/properties/shorthand/position.mako.rs
@@ -11,8 +11,10 @@
                     spec="https://drafts.csswg.org/css-flexbox/#flex-flow-property">
     use properties::longhands::{flex_direction, flex_wrap};
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         let mut direction = None;
         let mut wrap = None;
         loop {
diff --git a/components/style/properties/shorthand/text.mako.rs b/components/style/properties/shorthand/text.mako.rs
index c53f1b8b27e..18a0786494d 100644
--- a/components/style/properties/shorthand/text.mako.rs
+++ b/components/style/properties/shorthand/text.mako.rs
@@ -16,8 +16,10 @@
         use properties::longhands::text_decoration_line;
     % endif
 
-    pub fn parse_value<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                               -> Result<Longhands, ParseError<'i>> {
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
         % if product == "gecko":
             let (mut line, mut style, mut color, mut any) = (None, None, None, false);
         % else:
diff --git a/components/style/values/specified/length.rs b/components/style/values/specified/length.rs
index e3325794ab2..830c0828ecd 100644
--- a/components/style/values/specified/length.rs
+++ b/components/style/values/specified/length.rs
@@ -601,17 +601,20 @@ impl Length {
 
     /// Parse a non-negative length
     #[inline]
-    pub fn parse_non_negative<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-                                      -> Result<Length, ParseError<'i>> {
+    pub fn parse_non_negative<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Self, ParseError<'i>> {
         Self::parse_non_negative_quirky(context, input, AllowQuirks::No)
     }
 
     /// Parse a non-negative length, allowing quirks.
     #[inline]
-    pub fn parse_non_negative_quirky<'i, 't>(context: &ParserContext,
-                                             input: &mut Parser<'i, 't>,
-                                             allow_quirks: AllowQuirks)
-                                             -> Result<Length, ParseError<'i>> {
+    pub fn parse_non_negative_quirky<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+        allow_quirks: AllowQuirks,
+    ) -> Result<Self, ParseError<'i>> {
         Self::parse_internal(context, input, AllowedNumericType::NonNegative, allow_quirks)
     }
 
@@ -630,10 +633,11 @@ impl Parse for Length {
 
 impl Length {
     /// Parses a length, with quirks.
-    pub fn parse_quirky<'i, 't>(context: &ParserContext,
-                                input: &mut Parser<'i, 't>,
-                                allow_quirks: AllowQuirks)
-                                -> Result<Self, ParseError<'i>> {
+    pub fn parse_quirky<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+        allow_quirks: AllowQuirks,
+    ) -> Result<Self, ParseError<'i>> {
         Self::parse_internal(context, input, AllowedNumericType::All, allow_quirks)
     }
 }