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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
* file, You can obtain one at https://mozilla.org/MPL/2.0/. */
//! Common [values][values] used in CSS.
//!
#![deny(missing_docs)]
use crate::parser::{Parse, ParserContext};
use crate::values::distance::{ComputeSquaredDistance, SquaredDistance};
use crate::Atom;
pub use cssparser::{serialize_identifier, serialize_name, CowRcStr, Parser};
pub use cssparser::{SourceLocation, Token};
use precomputed_hash::PrecomputedHash;
use selectors::parser::SelectorParseErrorKind;
use std::fmt::{self, Debug, Write};
use style_traits::{CssWriter, ParseError, StyleParseErrorKind, ToCss};
use to_shmem::impl_trivial_to_shmem;
#[cfg(feature = "gecko")]
pub use crate::gecko::url::CssUrl;
#[cfg(feature = "servo")]
pub use crate::servo::url::CssUrl;
pub mod animated;
pub mod computed;
pub mod distance;
pub mod generics;
pub mod resolved;
pub mod specified;
/// A CSS float value.
pub type CSSFloat = f32;
/// Normalizes a float value to zero after a set of operations that might turn
/// it into NaN.
#[inline]
pub fn normalize(v: CSSFloat) -> CSSFloat {
if v.is_nan() {
0.0
} else {
v
}
}
/// A CSS integer value.
pub type CSSInteger = i32;
/// Serialize an identifier which is represented as an atom.
#[cfg(feature = "gecko")]
pub fn serialize_atom_identifier<W>(ident: &Atom, dest: &mut W) -> fmt::Result
where
W: Write,
{
ident.with_str(|s| serialize_identifier(s, dest))
}
/// Serialize an identifier which is represented as an atom.
#[cfg(feature = "servo")]
pub fn serialize_atom_identifier<Static, W>(
ident: &::string_cache::Atom<Static>,
dest: &mut W,
) -> fmt::Result
where
Static: string_cache::StaticAtomSet,
W: Write,
{
serialize_identifier(&ident, dest)
}
/// Serialize a name which is represented as an Atom.
#[cfg(feature = "gecko")]
pub fn serialize_atom_name<W>(ident: &Atom, dest: &mut W) -> fmt::Result
where
W: Write,
{
ident.with_str(|s| serialize_name(s, dest))
}
/// Serialize a name which is represented as an Atom.
#[cfg(feature = "servo")]
pub fn serialize_atom_name<Static, W>(
ident: &::string_cache::Atom<Static>,
dest: &mut W,
) -> fmt::Result
where
Static: string_cache::StaticAtomSet,
W: Write,
{
serialize_name(&ident, dest)
}
/// Serialize a number with calc, and NaN/infinity handling (if enabled)
pub fn serialize_number<W>(v: f32, was_calc: bool, dest: &mut CssWriter<W>) -> fmt::Result
where
W: Write,
{
serialize_specified_dimension(v, "", was_calc, dest)
}
/// Serialize a specified dimension with unit, calc, and NaN/infinity handling (if enabled)
pub fn serialize_specified_dimension<W>(
v: f32,
unit: &str,
was_calc: bool,
dest: &mut CssWriter<W>,
) -> fmt::Result
where
W: Write,
{
if was_calc {
dest.write_str("calc(")?;
}
if !v.is_finite() {
// "While not technically numbers, these keywords act as numeric values,
// similar to e and pi. Thus to get an infinite length, for example,
// requires an expression like calc(infinity * 1px)."
if v.is_nan() {
dest.write_str("NaN")?;
} else if v == f32::INFINITY {
dest.write_str("infinity")?;
} else if v == f32::NEG_INFINITY {
dest.write_str("-infinity")?;
}
if !unit.is_empty() {
dest.write_str(" * 1")?;
}
} else {
v.to_css(dest)?;
}
dest.write_str(unit)?;
if was_calc {
dest.write_char(')')?;
}
Ok(())
}
/// A CSS string stored as an `Atom`.
#[repr(transparent)]
#[derive(
Clone,
Debug,
Default,
Deref,
Eq,
Hash,
MallocSizeOf,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToResolvedValue,
ToShmem,
)]
pub struct AtomString(pub Atom);
#[cfg(feature = "servo")]
impl AsRef<str> for AtomString {
fn as_ref(&self) -> &str {
&*self.0
}
}
impl Parse for AtomString {
fn parse<'i>(_: &ParserContext, input: &mut Parser<'i, '_>) -> Result<Self, ParseError<'i>> {
Ok(Self(Atom::from(input.expect_string()?.as_ref())))
}
}
impl cssparser::ToCss for AtomString {
fn to_css<W>(&self, dest: &mut W) -> fmt::Result
where
W: Write,
{
// Wrap in quotes to form a string literal
dest.write_char('"')?;
#[cfg(feature = "servo")]
{
cssparser::CssStringWriter::new(dest).write_str(self.as_ref())?;
}
#[cfg(feature = "gecko")]
{
self.0
.with_str(|s| cssparser::CssStringWriter::new(dest).write_str(s))?;
}
dest.write_char('"')
}
}
impl style_traits::ToCss for AtomString {
fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
where
W: Write,
{
cssparser::ToCss::to_css(self, dest)
}
}
impl PrecomputedHash for AtomString {
#[inline]
fn precomputed_hash(&self) -> u32 {
self.0.precomputed_hash()
}
}
impl<'a> From<&'a str> for AtomString {
#[inline]
fn from(string: &str) -> Self {
Self(Atom::from(string))
}
}
/// A generic CSS `<ident>` stored as an `Atom`.
#[cfg(feature = "servo")]
#[repr(transparent)]
#[derive(Deref)]
pub struct GenericAtomIdent<Set>(pub string_cache::Atom<Set>)
where
Set: string_cache::StaticAtomSet;
/// A generic CSS `<ident>` stored as an `Atom`, for the default atom set.
#[cfg(feature = "servo")]
pub type AtomIdent = GenericAtomIdent<servo_atoms::AtomStaticSet>;
#[cfg(feature = "servo")]
impl<Set: string_cache::StaticAtomSet> style_traits::SpecifiedValueInfo for GenericAtomIdent<Set> {}
#[cfg(feature = "servo")]
impl<Set: string_cache::StaticAtomSet> Default for GenericAtomIdent<Set> {
fn default() -> Self {
Self(string_cache::Atom::default())
}
}
#[cfg(feature = "servo")]
impl<Set: string_cache::StaticAtomSet> std::fmt::Debug for GenericAtomIdent<Set> {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
self.0.fmt(f)
}
}
#[cfg(feature = "servo")]
impl<Set: string_cache::StaticAtomSet> std::hash::Hash for GenericAtomIdent<Set> {
fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
self.0.hash(state)
}
}
#[cfg(feature = "servo")]
impl<Set: string_cache::StaticAtomSet> Eq for GenericAtomIdent<Set> {}
#[cfg(feature = "servo")]
impl<Set: string_cache::StaticAtomSet> PartialEq for GenericAtomIdent<Set> {
fn eq(&self, other: &Self) -> bool {
self.0 == other.0
}
}
#[cfg(feature = "servo")]
impl<Set: string_cache::StaticAtomSet> Clone for GenericAtomIdent<Set> {
fn clone(&self) -> Self {
Self(self.0.clone())
}
}
#[cfg(feature = "servo")]
impl<Set: string_cache::StaticAtomSet> to_shmem::ToShmem for GenericAtomIdent<Set> {
fn to_shmem(&self, builder: &mut to_shmem::SharedMemoryBuilder) -> to_shmem::Result<Self> {
use std::mem::ManuallyDrop;
let atom = self.0.to_shmem(builder)?;
Ok(ManuallyDrop::new(Self(ManuallyDrop::into_inner(atom))))
}
}
#[cfg(feature = "servo")]
impl<Set: string_cache::StaticAtomSet> malloc_size_of::MallocSizeOf for GenericAtomIdent<Set> {
fn size_of(&self, ops: &mut malloc_size_of::MallocSizeOfOps) -> usize {
self.0.size_of(ops)
}
}
#[cfg(feature = "servo")]
impl<Set: string_cache::StaticAtomSet> cssparser::ToCss for GenericAtomIdent<Set> {
fn to_css<W>(&self, dest: &mut W) -> fmt::Result
where
W: Write,
{
serialize_atom_identifier(&self.0, dest)
}
}
#[cfg(feature = "servo")]
impl<Set: string_cache::StaticAtomSet> PrecomputedHash for GenericAtomIdent<Set> {
#[inline]
fn precomputed_hash(&self) -> u32 {
self.0.precomputed_hash()
}
}
#[cfg(feature = "servo")]
impl<'a, Set: string_cache::StaticAtomSet> From<&'a str> for GenericAtomIdent<Set> {
#[inline]
fn from(string: &str) -> Self {
Self(string_cache::Atom::from(string))
}
}
#[cfg(feature = "servo")]
impl<Set: string_cache::StaticAtomSet> std::borrow::Borrow<string_cache::Atom<Set>>
for GenericAtomIdent<Set>
{
#[inline]
fn borrow(&self) -> &string_cache::Atom<Set> {
&self.0
}
}
#[cfg(feature = "servo")]
impl<Set: string_cache::StaticAtomSet> GenericAtomIdent<Set> {
/// Constructs a new GenericAtomIdent.
#[inline]
pub fn new(atom: string_cache::Atom<Set>) -> Self {
Self(atom)
}
/// Cast an atom ref to an AtomIdent ref.
#[inline]
pub fn cast<'a>(atom: &'a string_cache::Atom<Set>) -> &'a Self {
let ptr = atom as *const _ as *const Self;
// safety: repr(transparent)
unsafe { &*ptr }
}
}
/// A CSS `<ident>` stored as an `Atom`.
#[cfg(feature = "gecko")]
#[repr(transparent)]
#[derive(
Clone, Debug, Default, Deref, Eq, Hash, MallocSizeOf, PartialEq, SpecifiedValueInfo, ToShmem,
)]
pub struct AtomIdent(pub Atom);
#[cfg(feature = "gecko")]
impl cssparser::ToCss for AtomIdent {
fn to_css<W>(&self, dest: &mut W) -> fmt::Result
where
W: Write,
{
serialize_atom_identifier(&self.0, dest)
}
}
#[cfg(feature = "gecko")]
impl style_traits::ToCss for AtomIdent {
fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
where
W: Write,
{
cssparser::ToCss::to_css(self, dest)
}
}
#[cfg(feature = "gecko")]
impl PrecomputedHash for AtomIdent {
#[inline]
fn precomputed_hash(&self) -> u32 {
self.0.precomputed_hash()
}
}
#[cfg(feature = "gecko")]
impl<'a> From<&'a str> for AtomIdent {
#[inline]
fn from(string: &str) -> Self {
Self(Atom::from(string))
}
}
#[cfg(feature = "gecko")]
impl AtomIdent {
/// Constructs a new AtomIdent.
#[inline]
pub fn new(atom: Atom) -> Self {
Self(atom)
}
/// Like `Atom::with` but for `AtomIdent`.
pub unsafe fn with<F, R>(ptr: *const crate::gecko_bindings::structs::nsAtom, callback: F) -> R
where
F: FnOnce(&Self) -> R,
{
Atom::with(ptr, |atom: &Atom| {
// safety: repr(transparent)
let atom = atom as *const Atom as *const AtomIdent;
callback(&*atom)
})
}
/// Cast an atom ref to an AtomIdent ref.
#[inline]
pub fn cast<'a>(atom: &'a Atom) -> &'a Self {
let ptr = atom as *const _ as *const Self;
// safety: repr(transparent)
unsafe { &*ptr }
}
}
#[cfg(feature = "gecko")]
impl std::borrow::Borrow<crate::gecko_string_cache::WeakAtom> for AtomIdent {
#[inline]
fn borrow(&self) -> &crate::gecko_string_cache::WeakAtom {
self.0.borrow()
}
}
/// Serialize a value into percentage.
pub fn serialize_percentage<W>(value: CSSFloat, dest: &mut CssWriter<W>) -> fmt::Result
where
W: Write,
{
serialize_specified_dimension(value * 100., "%", /* was_calc = */ false, dest)
}
/// Serialize a value into normalized (no NaN/inf serialization) percentage.
pub fn serialize_normalized_percentage<W>(value: CSSFloat, dest: &mut CssWriter<W>) -> fmt::Result
where
W: Write,
{
(value * 100.).to_css(dest)?;
dest.write_char('%')
}
/// Convenience void type to disable some properties and values through types.
#[cfg_attr(feature = "servo", derive(Deserialize, MallocSizeOf, Serialize))]
#[derive(
Clone,
Copy,
Debug,
PartialEq,
SpecifiedValueInfo,
ToAnimatedValue,
ToComputedValue,
ToCss,
ToResolvedValue,
)]
pub enum Impossible {}
// FIXME(nox): This should be derived but the derive code cannot cope
// with uninhabited enums.
impl ComputeSquaredDistance for Impossible {
#[inline]
fn compute_squared_distance(&self, _other: &Self) -> Result<SquaredDistance, ()> {
match *self {}
}
}
impl_trivial_to_shmem!(Impossible);
impl Parse for Impossible {
fn parse<'i, 't>(
_context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError))
}
}
/// A struct representing one of two kinds of values.
#[derive(
Animate,
Clone,
ComputeSquaredDistance,
Copy,
MallocSizeOf,
PartialEq,
Parse,
SpecifiedValueInfo,
ToAnimatedValue,
ToAnimatedZero,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
pub enum Either<A, B> {
/// The first value.
First(A),
/// The second kind of value.
Second(B),
}
impl<A: Debug, B: Debug> Debug for Either<A, B> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match *self {
Either::First(ref v) => v.fmt(f),
Either::Second(ref v) => v.fmt(f),
}
}
}
#[derive(
Clone,
Debug,
Default,
Eq,
Hash,
MallocSizeOf,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToResolvedValue,
ToShmem,
)]
#[repr(C)]
pub struct CustomIdent(pub Atom);
impl CustomIdent {
/// Parse a <custom-ident>
///
/// TODO(zrhoffman, bug 1844501): Use CustomIdent::parse in more places instead of
/// CustomIdent::from_ident.
pub fn parse<'i, 't>(
input: &mut Parser<'i, 't>,
invalid: &[&str],
) -> Result<Self, ParseError<'i>> {
let location = input.current_source_location();
let ident = input.expect_ident()?;
CustomIdent::from_ident(location, ident, invalid)
}
/// Parse an already-tokenizer identifier
pub fn from_ident<'i>(
location: SourceLocation,
ident: &CowRcStr<'i>,
excluding: &[&str],
) -> Result<Self, ParseError<'i>> {
if !Self::is_valid(ident, excluding) {
return Err(
location.new_custom_error(SelectorParseErrorKind::UnexpectedIdent(ident.clone()))
);
}
if excluding.iter().any(|s| ident.eq_ignore_ascii_case(s)) {
Err(location.new_custom_error(StyleParseErrorKind::UnspecifiedError))
} else {
Ok(CustomIdent(Atom::from(ident.as_ref())))
}
}
fn is_valid(ident: &str, excluding: &[&str]) -> bool {
use crate::properties::CSSWideKeyword;
//
// The CSS-wide keywords are not valid <custom-ident>s. The default
// keyword is reserved and is also not a valid <custom-ident>.
if CSSWideKeyword::from_ident(ident).is_ok() || ident.eq_ignore_ascii_case("default") {
return false;
}
//
// Excluded keywords are excluded in all ASCII case permutations.
!excluding.iter().any(|s| ident.eq_ignore_ascii_case(s))
}
}
impl ToCss for CustomIdent {
fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
where
W: Write,
{
serialize_atom_identifier(&self.0, dest)
}
}
/// This is simply an Atom, but will only parse if the identifier starts with "--".
#[repr(transparent)]
#[derive(
Clone,
Debug,
Eq,
Hash,
MallocSizeOf,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToResolvedValue,
ToShmem,
)]
pub struct DashedIdent(pub Atom);
impl DashedIdent {
/// Parse an already-tokenizer identifier
pub fn from_ident<'i>(
location: SourceLocation,
ident: &CowRcStr<'i>,
) -> Result<Self, ParseError<'i>> {
if !ident.starts_with("--") {
return Err(
location.new_custom_error(SelectorParseErrorKind::UnexpectedIdent(ident.clone()))
);
}
Ok(Self(Atom::from(ident.as_ref())))
}
/// Special value for internal use. Useful where we can't use Option<>.
pub fn empty() -> Self {
Self(atom!(""))
}
/// Check for special internal value.
pub fn is_empty(&self) -> bool {
self.0 == atom!("")
}
}
impl Parse for DashedIdent {
fn parse<'i, 't>(
_: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
let location = input.current_source_location();
let ident = input.expect_ident()?;
Self::from_ident(location, ident)
}
}
impl ToCss for DashedIdent {
fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
where
W: Write,
{
serialize_atom_identifier(&self.0, dest)
}
}
/// The <keyframes-name>.
///
///
/// We use a single atom for this. Empty atom represents `none` animation.
#[repr(transparent)]
#[derive(
Clone,
Debug,
Eq,
Hash,
PartialEq,
MallocSizeOf,
SpecifiedValueInfo,
ToComputedValue,
ToResolvedValue,
ToShmem,
)]
pub struct KeyframesName(Atom);
impl KeyframesName {
pub fn from_ident(value: &str) -> Self {
Self(Atom::from(value))
}
/// Returns the `none` value.
pub fn none() -> Self {
Self(atom!(""))
}
/// Returns whether this is the special `none` value.
pub fn is_none(&self) -> bool {
self.0 == atom!("")
}
/// Create a new KeyframesName from Atom.
#[cfg(feature = "gecko")]
pub fn from_atom(atom: Atom) -> Self {
Self(atom)
}
/// The name as an Atom
pub fn as_atom(&self) -> &Atom {
&self.0
}
}
impl Parse for KeyframesName {
fn parse<'i, 't>(
_: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
let location = input.current_source_location();
Ok(match *input.next()? {
Token::Ident(ref s) => Self(CustomIdent::from_ident(location, s, &["none"])?.0),
Token::QuotedString(ref s) => Self(Atom::from(s.as_ref())),
ref t => return Err(location.new_unexpected_token_error(t.clone())),
})
}
}
impl ToCss for KeyframesName {
fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
where
W: Write,
{
if self.is_none() {
return dest.write_str("none");
}
self.0.with_str(|s| {
if CustomIdent::is_valid(s, &["none"]) {
serialize_identifier(s, dest)
} else {
s.to_css(dest)
}
})
}
}