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/* 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
//! The [`@font-feature-values`][font-feature-values] at-rule.
//!
use crate::error_reporting::ContextualParseError;
#[cfg(feature = "gecko")]
use crate::gecko_bindings::bindings::Gecko_AppendFeatureValueHashEntry;
#[cfg(feature = "gecko")]
use crate::gecko_bindings::structs::{self, gfxFontFeatureValueSet};
use crate::parser::{Parse, ParserContext};
use crate::shared_lock::{SharedRwLockReadGuard, ToCssWithGuard};
use crate::str::CssStringWriter;
use crate::stylesheets::CssRuleType;
use crate::values::computed::font::FamilyName;
use crate::values::serialize_atom_identifier;
use crate::Atom;
use cssparser::{
AtRuleParser, BasicParseErrorKind, CowRcStr, DeclarationParser, Parser, ParserState,
QualifiedRuleParser, RuleBodyItemParser, RuleBodyParser, SourceLocation, Token,
};
use std::fmt::{self, Write};
use style_traits::{CssWriter, ParseError, StyleParseErrorKind, ToCss};
#[cfg(feature = "gecko")] use thin_vec::ThinVec;
/// A @font-feature-values block declaration.
/// It is `<ident>: <integer>+`.
/// This struct can take 3 value types.
/// - `SingleValue` is to keep just one unsigned integer value.
/// - `PairValues` is to keep one or two unsigned integer values.
/// - `VectorValues` is to keep a list of unsigned integer values.
#[derive(Clone, Debug, PartialEq, ToShmem)]
pub struct FFVDeclaration<T> {
/// An `<ident>` for declaration name.
pub name: Atom,
/// An `<integer>+` for declaration value.
pub value: T,
}
impl<T: ToCss> ToCss for FFVDeclaration<T> {
fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
where
W: Write,
{
serialize_atom_identifier(&self.name, dest)?;
dest.write_str(": ")?;
self.value.to_css(dest)?;
dest.write_char(';')
}
}
/// A trait for @font-feature-values rule to gecko values conversion.
#[cfg(feature = "gecko")]
pub trait ToGeckoFontFeatureValues {
/// Sets the equivalent of declaration to gecko `ThinVec<u32>` array.
fn to_gecko_font_feature_values(&self) -> ThinVec<u32>;
}
/// A @font-feature-values block declaration value that keeps one value.
#[derive(Clone, Debug, PartialEq, ToCss, ToShmem)]
pub struct SingleValue(pub u32);
impl Parse for SingleValue {
fn parse<'i, 't>(
_context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<SingleValue, ParseError<'i>> {
let location = input.current_source_location();
match *input.next()? {
Token::Number {
int_value: Some(v), ..
} if v >= 0 => Ok(SingleValue(v as u32)),
ref t => Err(location.new_unexpected_token_error(t.clone())),
}
}
}
#[cfg(feature = "gecko")]
impl ToGeckoFontFeatureValues for SingleValue {
fn to_gecko_font_feature_values(&self) -> ThinVec<u32> {
thin_vec::thin_vec![self.0 as u32]
}
}
/// A @font-feature-values block declaration value that keeps one or two values.
#[derive(Clone, Debug, PartialEq, ToCss, ToShmem)]
pub struct PairValues(pub u32, pub Option<u32>);
impl Parse for PairValues {
fn parse<'i, 't>(
_context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<PairValues, ParseError<'i>> {
let location = input.current_source_location();
let first = match *input.next()? {
Token::Number {
int_value: Some(a), ..
} if a >= 0 => a as u32,
ref t => return Err(location.new_unexpected_token_error(t.clone())),
};
let location = input.current_source_location();
match input.next() {
Ok(&Token::Number {
int_value: Some(b), ..
}) if b >= 0 => Ok(PairValues(first, Some(b as u32))),
// It can't be anything other than number.
Ok(t) => Err(location.new_unexpected_token_error(t.clone())),
// It can be just one value.
Err(_) => Ok(PairValues(first, None)),
}
}
}
#[cfg(feature = "gecko")]
impl ToGeckoFontFeatureValues for PairValues {
fn to_gecko_font_feature_values(&self) -> ThinVec<u32> {
let mut result = thin_vec::thin_vec![self.0 as u32];
if let Some(second) = self.1 {
result.push(second as u32);
}
result
}
}
/// A @font-feature-values block declaration value that keeps a list of values.
#[derive(Clone, Debug, PartialEq, ToCss, ToShmem)]
pub struct VectorValues(#[css(iterable)] pub Vec<u32>);
impl Parse for VectorValues {
fn parse<'i, 't>(
_context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<VectorValues, ParseError<'i>> {
let mut vec = vec![];
loop {
let location = input.current_source_location();
match input.next() {
Ok(&Token::Number {
int_value: Some(a), ..
}) if a >= 0 => {
vec.push(a as u32);
},
// It can't be anything other than number.
Ok(t) => return Err(location.new_unexpected_token_error(t.clone())),
Err(_) => break,
}
}
if vec.len() == 0 {
return Err(input.new_error(BasicParseErrorKind::EndOfInput));
}
Ok(VectorValues(vec))
}
}
#[cfg(feature = "gecko")]
impl ToGeckoFontFeatureValues for VectorValues {
fn to_gecko_font_feature_values(&self) -> ThinVec<u32> {
self.0.iter().copied().collect()
}
}
/// Parses a list of `FamilyName`s.
pub fn parse_family_name_list<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Vec<FamilyName>, ParseError<'i>> {
input
.parse_comma_separated(|i| FamilyName::parse(context, i))
.map_err(|e| e.into())
}
/// @font-feature-values inside block parser. Parses a list of `FFVDeclaration`.
/// (`<ident>: <integer>+`)
struct FFVDeclarationsParser<'a, 'b: 'a, T: 'a> {
context: &'a ParserContext<'b>,
declarations: &'a mut Vec<FFVDeclaration<T>>,
}
/// Default methods reject all at rules.
impl<'a, 'b, 'i, T> AtRuleParser<'i> for FFVDeclarationsParser<'a, 'b, T> {
type Prelude = ();
type AtRule = ();
type Error = StyleParseErrorKind<'i>;
}
impl<'a, 'b, 'i, T> QualifiedRuleParser<'i> for FFVDeclarationsParser<'a, 'b, T> {
type Prelude = ();
type QualifiedRule = ();
type Error = StyleParseErrorKind<'i>;
}
impl<'a, 'b, 'i, T> DeclarationParser<'i> for FFVDeclarationsParser<'a, 'b, T>
where
T: Parse,
{
type Declaration = ();
type Error = StyleParseErrorKind<'i>;
fn parse_value<'t>(
&mut self,
name: CowRcStr<'i>,
input: &mut Parser<'i, 't>,
) -> Result<(), ParseError<'i>> {
let value = input.parse_entirely(|i| T::parse(self.context, i))?;
let new = FFVDeclaration {
name: Atom::from(&*name),
value,
};
update_or_push(&mut self.declarations, new);
Ok(())
}
}
impl<'a, 'b, 'i, T> RuleBodyItemParser<'i, (), StyleParseErrorKind<'i>>
for FFVDeclarationsParser<'a, 'b, T>
where
T: Parse,
{
fn parse_declarations(&self) -> bool {
true
}
fn parse_qualified(&self) -> bool {
false
}
}
macro_rules! font_feature_values_blocks {
(
blocks = [
$( #[$doc: meta] $name: tt $ident: ident / $ident_camel: ident / $gecko_enum: ident: $ty: ty, )*
]
) => {
/// The [`@font-feature-values`][font-feature-values] at-rule.
///
#[derive(Clone, Debug, PartialEq, ToShmem)]
pub struct FontFeatureValuesRule {
/// Font family list for @font-feature-values rule.
/// Family names cannot contain generic families. FamilyName
/// also accepts only non-generic names.
pub family_names: Vec<FamilyName>,
$(
#[$doc]
pub $ident: Vec<FFVDeclaration<$ty>>,
)*
/// The line and column of the rule's source code.
pub source_location: SourceLocation,
}
impl FontFeatureValuesRule {
/// Creates an empty FontFeatureValuesRule with given location and family name list.
fn new(family_names: Vec<FamilyName>, location: SourceLocation) -> Self {
FontFeatureValuesRule {
family_names: family_names,
$(
$ident: vec![],
)*
source_location: location,
}
}
/// Parses a `FontFeatureValuesRule`.
pub fn parse(
context: &ParserContext,
input: &mut Parser,
family_names: Vec<FamilyName>,
location: SourceLocation,
) -> Self {
let mut rule = FontFeatureValuesRule::new(family_names, location);
let mut parser = FontFeatureValuesRuleParser {
context,
rule: &mut rule,
};
let mut iter = RuleBodyParser::new(input, &mut parser);
while let Some(result) = iter.next() {
if let Err((error, slice)) = result {
let location = error.location;
let error = ContextualParseError::UnsupportedRule(slice, error);
context.log_css_error(location, error);
}
}
rule
}
/// Prints inside of `@font-feature-values` block.
pub fn value_to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
where
W: Write,
{
$(
if self.$ident.len() > 0 {
dest.write_str(concat!("@", $name, " {\n"))?;
let iter = self.$ident.iter();
for val in iter {
val.to_css(dest)?;
dest.write_str("\n")?
}
dest.write_str("}\n")?
}
)*
Ok(())
}
/// Returns length of all at-rules.
pub fn len(&self) -> usize {
let mut len = 0;
$(
len += self.$ident.len();
)*
len
}
/// Convert to Gecko gfxFontFeatureValueSet.
#[cfg(feature = "gecko")]
pub fn set_at_rules(&self, dest: *mut gfxFontFeatureValueSet) {
for ref family in self.family_names.iter() {
let family = family.name.to_ascii_lowercase();
$(
if self.$ident.len() > 0 {
for val in self.$ident.iter() {
let array = unsafe {
Gecko_AppendFeatureValueHashEntry(
dest,
family.as_ptr(),
structs::$gecko_enum,
val.name.as_ptr()
)
};
unsafe {
*array = val.value.to_gecko_font_feature_values();
}
}
}
)*
}
}
}
impl ToCssWithGuard for FontFeatureValuesRule {
fn to_css(&self, _guard: &SharedRwLockReadGuard, dest: &mut CssStringWriter) -> fmt::Result {
dest.write_str("@font-feature-values ")?;
self.family_names.to_css(&mut CssWriter::new(dest))?;
dest.write_str(" {\n")?;
self.value_to_css(&mut CssWriter::new(dest))?;
dest.write_char('}')
}
}
/// Updates with new value if same `ident` exists, otherwise pushes to the vector.
fn update_or_push<T>(vec: &mut Vec<FFVDeclaration<T>>, element: FFVDeclaration<T>) {
if let Some(item) = vec.iter_mut().find(|item| item.name == element.name) {
item.value = element.value;
} else {
vec.push(element);
}
}
/// Keeps the information about block type like @swash, @styleset etc.
enum BlockType {
$(
$ident_camel,
)*
}
/// Parser for `FontFeatureValuesRule`. Parses all blocks
/// <feature-type> {
/// <feature-value-declaration-list>
/// }
/// <feature-type> = @stylistic | @historical-forms | @styleset |
/// @character-variant | @swash | @ornaments | @annotation
struct FontFeatureValuesRuleParser<'a> {
context: &'a ParserContext<'a>,
rule: &'a mut FontFeatureValuesRule,
}
/// Default methods reject all qualified rules.
impl<'a, 'i> QualifiedRuleParser<'i> for FontFeatureValuesRuleParser<'a> {
type Prelude = ();
type QualifiedRule = ();
type Error = StyleParseErrorKind<'i>;
}
impl<'a, 'i> AtRuleParser<'i> for FontFeatureValuesRuleParser<'a> {
type Prelude = BlockType;
type AtRule = ();
type Error = StyleParseErrorKind<'i>;
fn parse_prelude<'t>(
&mut self,
name: CowRcStr<'i>,
input: &mut Parser<'i, 't>,
) -> Result<BlockType, ParseError<'i>> {
match_ignore_ascii_case! { &*name,
$(
$name => Ok(BlockType::$ident_camel),
)*
_ => Err(input.new_error(BasicParseErrorKind::AtRuleBodyInvalid)),
}
}
fn parse_block<'t>(
&mut self,
prelude: BlockType,
_: &ParserState,
input: &mut Parser<'i, 't>
) -> Result<Self::AtRule, ParseError<'i>> {
debug_assert!(self.context.rule_types().contains(CssRuleType::FontFeatureValues));
match prelude {
$(
BlockType::$ident_camel => {
let mut parser = FFVDeclarationsParser {
context: &self.context,
declarations: &mut self.rule.$ident,
};
let mut iter = RuleBodyParser::new(input, &mut parser);
while let Some(declaration) = iter.next() {
if let Err((error, slice)) = declaration {
let location = error.location;
// TODO(emilio): Maybe add a more specific error kind for
// font-feature-values descriptors.
let error = ContextualParseError::UnsupportedPropertyDeclaration(slice, error, &[]);
self.context.log_css_error(location, error);
}
}
},
)*
}
Ok(())
}
}
impl<'a, 'i> DeclarationParser<'i> for FontFeatureValuesRuleParser<'a> {
type Declaration = ();
type Error = StyleParseErrorKind<'i>;
}
impl<'a, 'i> RuleBodyItemParser<'i, (), StyleParseErrorKind<'i>> for FontFeatureValuesRuleParser<'a> {
fn parse_declarations(&self) -> bool { false }
fn parse_qualified(&self) -> bool { true }
}
}
}
font_feature_values_blocks! {
blocks = [
#[doc = "A @swash blocksck. \
Specifies a feature name that will work with the swash() \
functional notation of font-variant-alternates."]
"swash" swash / Swash / NS_FONT_VARIANT_ALTERNATES_SWASH: SingleValue,
#[doc = "A @stylistic block. \
Specifies a feature name that will work with the annotation() \
functional notation of font-variant-alternates."]
"stylistic" stylistic / Stylistic / NS_FONT_VARIANT_ALTERNATES_STYLISTIC: SingleValue,
#[doc = "A @ornaments block. \
Specifies a feature name that will work with the ornaments() ] \
functional notation of font-variant-alternates."]
"ornaments" ornaments / Ornaments / NS_FONT_VARIANT_ALTERNATES_ORNAMENTS: SingleValue,
#[doc = "A @annotation block. \
Specifies a feature name that will work with the stylistic() \
functional notation of font-variant-alternates."]
"annotation" annotation / Annotation / NS_FONT_VARIANT_ALTERNATES_ANNOTATION: SingleValue,
#[doc = "A @character-variant block. \
Specifies a feature name that will work with the styleset() \
functional notation of font-variant-alternates. The value can be a pair."]
"character-variant" character_variant / CharacterVariant / NS_FONT_VARIANT_ALTERNATES_CHARACTER_VARIANT:
PairValues,
#[doc = "A @styleset block. \
Specifies a feature name that will work with the character-variant() \
functional notation of font-variant-alternates. The value can be a list."]
"styleset" styleset / Styleset / NS_FONT_VARIANT_ALTERNATES_STYLESET: VectorValues,
]
}