servo/components/style/properties/helpers.mako.rs
2016-08-16 22:28:51 -04:00

541 lines
23 KiB
Rust

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
<%! from data import Keyword, to_rust_ident, to_camel_case %>
<%def name="longhand(name, **kwargs)">
<%call expr="raw_longhand(name, **kwargs)">
${caller.body()}
% if not data.longhands_by_name[name].derived_from:
pub fn parse_specified(context: &ParserContext, input: &mut Parser)
-> Result<DeclaredValue<SpecifiedValue>, ()> {
parse(context, input).map(DeclaredValue::Value)
}
% endif
</%call>
</%def>
<%def name="predefined_type(name, type, initial_value, parse_method='parse', **kwargs)">
<%call expr="longhand(name, predefined_type=type, **kwargs)">
#[allow(unused_imports)]
use app_units::Au;
use cssparser::{Color as CSSParserColor, RGBA};
pub type SpecifiedValue = specified::${type};
pub mod computed_value {
pub use values::computed::${type} as T;
}
#[inline] pub fn get_initial_value() -> computed_value::T { ${initial_value} }
#[inline] pub fn parse(_context: &ParserContext, input: &mut Parser)
-> Result<SpecifiedValue, ()> {
specified::${type}::${parse_method}(input)
}
</%call>
</%def>
// FIXME (Manishearth): Add computed_value_as_specified argument
// and handle the empty case correctly
<%doc>
To be used in cases where we have a grammar like
"<thing> [ , <thing> ]*". `gecko_only` should be set
to True for cases where Servo takes a single value
and Stylo supports vector values.
Setting allow_empty to False allows for cases where the vector
is empty. The grammar for these is usually "none | <thing> [ , <thing> ]*".
We assume that the default/initial value is an empty vector for these.
`initial_value` need not be defined for these.
</%doc>
<%def name="vector_longhand(name, gecko_only=False, allow_empty=False, **kwargs)">
<%call expr="longhand(name, **kwargs)">
% if product == "gecko" or not gecko_only:
use cssparser::ToCss;
use std::fmt;
use values::HasViewportPercentage;
impl HasViewportPercentage for SpecifiedValue {
fn has_viewport_percentage(&self) -> bool {
let &SpecifiedValue(ref vec) = self;
vec.iter().any(|ref x| x.has_viewport_percentage())
}
}
pub mod single_value {
use cssparser::Parser;
use parser::{ParserContext, ParserContextExtraData};
use properties::{CSSWideKeyword, DeclaredValue, Shorthand};
use values::computed::{Context, ToComputedValue};
use values::{computed, specified};
${caller.body()}
}
pub mod computed_value {
use super::single_value;
#[derive(Debug, Clone, PartialEq)]
#[cfg_attr(feature = "servo", derive(HeapSizeOf))]
pub struct T(pub Vec<single_value::computed_value::T>);
}
impl ToCss for computed_value::T {
fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
let mut iter = self.0.iter();
if let Some(val) = iter.next() {
try!(val.to_css(dest));
} else {
% if allow_empty:
try!(dest.write_str("none"));
% else:
error!("Found empty value for property ${name}");
% endif
}
for i in iter {
try!(dest.write_str(", "));
try!(i.to_css(dest));
}
Ok(())
}
}
#[derive(Debug, Clone, PartialEq)]
#[cfg_attr(feature = "servo", derive(HeapSizeOf))]
pub struct SpecifiedValue(pub Vec<single_value::SpecifiedValue>);
impl ToCss for SpecifiedValue {
fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
let mut iter = self.0.iter();
if let Some(val) = iter.next() {
try!(val.to_css(dest));
} else {
% if allow_empty:
try!(dest.write_str("none"));
% else:
error!("Found empty value for property ${name}");
% endif
}
for i in iter {
try!(dest.write_str(", "));
try!(i.to_css(dest));
}
Ok(())
}
}
pub fn get_initial_value() -> computed_value::T {
% if allow_empty:
computed_value::T(vec![])
% else:
computed_value::T(vec![single_value::get_initial_value()])
% endif
}
pub fn parse(context: &ParserContext, input: &mut Parser) -> Result<SpecifiedValue, ()> {
% if allow_empty:
if input.try(|input| input.expect_ident_matching("none")).is_ok() {
Ok(SpecifiedValue(Vec::new()))
} else {
input.parse_comma_separated(|parser| {
single_value::parse(context, parser)
}).map(SpecifiedValue)
}
% else:
input.parse_comma_separated(|parser| {
single_value::parse(context, parser)
}).map(SpecifiedValue)
% endif
}
impl ToComputedValue for SpecifiedValue {
type ComputedValue = computed_value::T;
#[inline]
fn to_computed_value(&self, context: &Context) -> computed_value::T {
computed_value::T(self.0.iter().map(|x| x.to_computed_value(context)).collect())
}
}
% else:
${caller.body()}
% endif
</%call>
</%def>
<%def name="raw_longhand(*args, **kwargs)">
<%
property = data.declare_longhand(*args, **kwargs)
if property is None:
return ""
%>
pub mod ${property.ident} {
#![allow(unused_imports)]
% if not property.derived_from:
use cssparser::Parser;
use parser::{ParserContext, ParserContextExtraData};
use properties::{CSSWideKeyword, DeclaredValue, Shorthand};
% endif
use cascade_info::CascadeInfo;
use error_reporting::ParseErrorReporter;
use properties::longhands;
use properties::property_bit_field::PropertyBitField;
use properties::{ComputedValues, PropertyDeclaration};
use properties::style_structs;
use std::boxed::Box as StdBox;
use std::collections::HashMap;
use std::sync::Arc;
use values::computed::{Context, ToComputedValue};
use values::{computed, specified};
use string_cache::Atom;
${caller.body()}
#[allow(unused_variables)]
pub fn cascade_property(declaration: &PropertyDeclaration,
inherited_style: &ComputedValues,
context: &mut computed::Context,
seen: &mut PropertyBitField,
cacheable: &mut bool,
cascade_info: &mut Option<<&mut CascadeInfo>,
error_reporter: &mut StdBox<ParseErrorReporter + Send>) {
let declared_value = match *declaration {
PropertyDeclaration::${property.camel_case}(ref declared_value) => {
declared_value
}
_ => panic!("entered the wrong cascade_property() implementation"),
};
% if not property.derived_from:
if seen.get_${property.ident}() {
return
}
seen.set_${property.ident}();
{
let custom_props = context.style().custom_properties();
::properties::substitute_variables_${property.ident}(
declared_value, &custom_props,
|value| {
if let Some(ref mut cascade_info) = *cascade_info {
cascade_info.on_cascade_property(&declaration,
&value);
}
match *value {
DeclaredValue::Value(ref specified_value) => {
let computed = specified_value.to_computed_value(context);
context.mutate_style().mutate_${data.current_style_struct.name_lower}()
.set_${property.ident}(computed);
}
DeclaredValue::WithVariables { .. } => unreachable!(),
DeclaredValue::Initial => {
// We assume that it's faster to use copy_*_from rather than
// set_*(get_initial_value());
let initial_struct = ComputedValues::initial_values()
.get_${data.current_style_struct.name_lower}();
context.mutate_style().mutate_${data.current_style_struct.name_lower}()
.copy_${property.ident}_from(initial_struct);
},
DeclaredValue::Inherit => {
// This is a bit slow, but this is rare so it shouldn't
// matter.
//
// FIXME: is it still?
*cacheable = false;
let inherited_struct =
inherited_style.get_${data.current_style_struct.name_lower}();
context.mutate_style().mutate_${data.current_style_struct.name_lower}()
.copy_${property.ident}_from(inherited_struct);
}
}
}, error_reporter);
}
% if property.custom_cascade:
cascade_property_custom(declaration,
inherited_style,
context,
seen,
cacheable,
error_reporter);
% endif
% else:
// Do not allow stylesheets to set derived properties.
% endif
}
% if not property.derived_from:
pub fn parse_declared(context: &ParserContext, input: &mut Parser)
-> Result<DeclaredValue<SpecifiedValue>, ()> {
match input.try(CSSWideKeyword::parse) {
Ok(CSSWideKeyword::InheritKeyword) => Ok(DeclaredValue::Inherit),
Ok(CSSWideKeyword::InitialKeyword) => Ok(DeclaredValue::Initial),
Ok(CSSWideKeyword::UnsetKeyword) => Ok(DeclaredValue::${
"Inherit" if data.current_style_struct.inherited else "Initial"}),
Err(()) => {
input.look_for_var_functions();
let start = input.position();
let specified = parse_specified(context, input);
if specified.is_err() {
while let Ok(_) = input.next() {} // Look for var() after the error.
}
let var = input.seen_var_functions();
if specified.is_err() && var {
input.reset(start);
let (first_token_type, css) = try!(
::custom_properties::parse_non_custom_with_var(input));
return Ok(DeclaredValue::WithVariables {
css: css.into_owned(),
first_token_type: first_token_type,
base_url: context.base_url.clone(),
from_shorthand: None,
})
}
specified
}
}
}
% endif
}
</%def>
<%def name="single_keyword(name, values, **kwargs)">
<%call expr="single_keyword_computed(name, values, **kwargs)">
use values::computed::ComputedValueAsSpecified;
use values::NoViewportPercentage;
impl ComputedValueAsSpecified for SpecifiedValue {}
impl NoViewportPercentage for SpecifiedValue {}
</%call>
</%def>
<%def name="single_keyword_computed(name, values, **kwargs)">
<%
keyword_kwargs = {a: kwargs.pop(a, None) for a in [
'gecko_constant_prefix', 'gecko_enum_prefix',
'extra_gecko_values', 'extra_servo_values',
]}
%>
<%call expr="longhand(name, keyword=Keyword(name, values, **keyword_kwargs), **kwargs)">
pub use self::computed_value::T as SpecifiedValue;
${caller.body()}
pub mod computed_value {
define_css_keyword_enum! { T:
% for value in data.longhands_by_name[name].keyword.values_for(product):
"${value}" => ${to_rust_ident(value)},
% endfor
}
}
#[inline]
pub fn get_initial_value() -> computed_value::T {
computed_value::T::${to_rust_ident(values.split()[0])}
}
#[inline]
pub fn parse(_context: &ParserContext, input: &mut Parser)
-> Result<SpecifiedValue, ()> {
computed_value::T::parse(input)
}
</%call>
</%def>
<%def name="keyword_list(name, values, **kwargs)">
<%
keyword_kwargs = {a: kwargs.pop(a, None) for a in [
'gecko_constant_prefix', 'gecko_enum_prefix',
'extra_gecko_values', 'extra_servo_values',
]}
%>
<%call expr="longhand(name, keyword=Keyword(name, values, **keyword_kwargs), **kwargs)">
use values::computed::ComputedValueAsSpecified;
pub use self::computed_value::T as SpecifiedValue;
use values::NoViewportPercentage;
impl NoViewportPercentage for SpecifiedValue {}
pub mod computed_value {
use cssparser::ToCss;
use std::fmt;
#[derive(Debug, Clone, PartialEq)]
#[cfg_attr(feature = "servo", derive(HeapSizeOf))]
pub struct T(pub Vec<${to_camel_case(name)}>);
impl ToCss for T {
fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
debug_assert!(!self.0.is_empty(), "Always parses at least one");
for (index, item) in self.0.iter().enumerate() {
if index != 0 {
try!(dest.write_str(", "));
}
try!(item.to_css(dest));
}
Ok(())
}
}
pub use self::${to_camel_case(name)} as SingleComputedValue;
define_css_keyword_enum! { ${to_camel_case(name)}:
% for value in data.longhands_by_name[name].keyword.values_for(product):
"${value}" => ${to_rust_ident(value)},
% endfor
}
}
pub use self::computed_value::${to_camel_case(name)} as SingleSpecifiedValue;
#[inline]
pub fn parse_one(input: &mut Parser) -> Result<SingleSpecifiedValue, ()> {
SingleSpecifiedValue::parse(input)
}
#[inline]
pub fn get_initial_value() -> computed_value::T {
computed_value::T(vec![get_initial_single_value()])
}
#[inline]
pub fn get_initial_single_value() -> SingleSpecifiedValue {
SingleSpecifiedValue::${to_rust_ident(values.split()[0])}
}
#[inline]
pub fn parse(_context: &ParserContext, input: &mut Parser)
-> Result<SpecifiedValue, ()> {
Ok(SpecifiedValue(try!(
input.parse_comma_separated(computed_value::${to_camel_case(name)}::parse))))
}
impl ComputedValueAsSpecified for SpecifiedValue {}
</%call>
</%def>
<%def name="shorthand(name, sub_properties, experimental=False, **kwargs)">
<%
shorthand = data.declare_shorthand(name, sub_properties.split(), experimental=experimental,
**kwargs)
%>
% if shorthand:
pub mod ${shorthand.ident} {
#[allow(unused_imports)]
use cssparser::{Parser, ToCss};
use parser::ParserContext;
use properties::{longhands, PropertyDeclaration, DeclaredValue, Shorthand};
use std::fmt;
pub struct Longhands {
% for sub_property in shorthand.sub_properties:
pub ${sub_property.ident}:
Option<longhands::${sub_property.ident}::SpecifiedValue>,
% endfor
}
/// Represents a serializable set of all of the longhand properties that correspond to a shorthand
pub struct LonghandsToSerialize<'a> {
% for sub_property in shorthand.sub_properties:
pub ${sub_property.ident}: &'a DeclaredValue<longhands::${sub_property.ident}::SpecifiedValue>,
% endfor
}
impl<'a> LonghandsToSerialize<'a> {
pub fn from_iter<I: Iterator<Item=&'a PropertyDeclaration>>(iter: I) -> Result<Self, ()> {
// Define all of the expected variables that correspond to the shorthand
% for sub_property in shorthand.sub_properties:
let mut ${sub_property.ident} = None;
% endfor
// Attempt to assign the incoming declarations to the expected variables
for longhand in iter {
match *longhand {
% for sub_property in shorthand.sub_properties:
PropertyDeclaration::${sub_property.camel_case}(ref value) => {
${sub_property.ident} = Some(value)
},
% endfor
_ => {}
};
}
// If any of the expected variables are missing, return an error
match (
% for sub_property in shorthand.sub_properties:
${sub_property.ident},
% endfor
) {
(
% for sub_property in shorthand.sub_properties:
Some(${sub_property.ident}),
% endfor
) =>
Ok(LonghandsToSerialize {
% for sub_property in shorthand.sub_properties:
${sub_property.ident}: ${sub_property.ident},
% endfor
}),
_ => Err(())
}
}
}
pub fn parse(context: &ParserContext, input: &mut Parser,
declarations: &mut Vec<PropertyDeclaration>)
-> Result<(), ()> {
input.look_for_var_functions();
let start = input.position();
let value = input.parse_entirely(|input| parse_value(context, input));
if value.is_err() {
while let Ok(_) = input.next() {} // Look for var() after the error.
}
let var = input.seen_var_functions();
if let Ok(value) = value {
% for sub_property in shorthand.sub_properties:
declarations.push(PropertyDeclaration::${sub_property.camel_case}(
match value.${sub_property.ident} {
Some(value) => DeclaredValue::Value(value),
None => DeclaredValue::Initial,
}
));
% endfor
Ok(())
} else if var {
input.reset(start);
let (first_token_type, css) = try!(
::custom_properties::parse_non_custom_with_var(input));
% for sub_property in shorthand.sub_properties:
declarations.push(PropertyDeclaration::${sub_property.camel_case}(
DeclaredValue::WithVariables {
css: css.clone().into_owned(),
first_token_type: first_token_type,
base_url: context.base_url.clone(),
from_shorthand: Some(Shorthand::${shorthand.camel_case}),
}
));
% endfor
Ok(())
} else {
Err(())
}
}
${caller.body()}
}
% endif
</%def>
<%def name="four_sides_shorthand(name, sub_property_pattern, parser_function)">
<%self:shorthand name="${name}" sub_properties="${
' '.join(sub_property_pattern % side
for side in ['top', 'right', 'bottom', 'left'])}">
use super::parse_four_sides;
use values::specified;
pub fn parse_value(_: &ParserContext, input: &mut Parser) -> Result<Longhands, ()> {
let (top, right, bottom, left) = try!(parse_four_sides(input, ${parser_function}));
Ok(Longhands {
% for side in ["top", "right", "bottom", "left"]:
${to_rust_ident(sub_property_pattern % side)}: Some(${side}),
% endfor
})
}
impl<'a> ToCss for LonghandsToSerialize<'a> {
fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
super::serialize_four_sides(
dest,
self.${to_rust_ident(sub_property_pattern % 'top')},
self.${to_rust_ident(sub_property_pattern % 'right')},
self.${to_rust_ident(sub_property_pattern % 'bottom')},
self.${to_rust_ident(sub_property_pattern % 'left')}
)
}
}
</%self:shorthand>
</%def>