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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
//! CSS handling for the specified value of
//! [`position`][position]s
//!
use crate::parser::{Parse, ParserContext};
use crate::selector_map::PrecomputedHashMap;
use crate::str::HTML_SPACE_CHARACTERS;
use crate::values::computed::LengthPercentage as ComputedLengthPercentage;
use crate::values::computed::{Context, Percentage, ToComputedValue};
use crate::values::generics::position::Position as GenericPosition;
use crate::values::generics::position::PositionComponent as GenericPositionComponent;
use crate::values::generics::position::PositionOrAuto as GenericPositionOrAuto;
use crate::values::generics::position::ZIndex as GenericZIndex;
use crate::values::generics::position::{AnchorSide, AspectRatio as GenericAspectRatio};
use crate::values::generics::position::{GenericAnchorFunction, GenericInset};
use crate::values::specified;
use crate::values::specified::{AllowQuirks, Integer, LengthPercentage, NonNegativeNumber};
use crate::values::DashedIdent;
use crate::{Atom, Zero};
use cssparser::Parser;
use selectors::parser::SelectorParseErrorKind;
use servo_arc::Arc;
use smallvec::{smallvec, SmallVec};
use std::collections::hash_map::Entry;
use std::fmt::{self, Write};
use style_traits::arc_slice::ArcSlice;
use style_traits::values::specified::AllowedNumericType;
use style_traits::{CssWriter, ParseError, StyleParseErrorKind, ToCss};
/// The specified value of a CSS `<position>`
pub type Position = GenericPosition<HorizontalPosition, VerticalPosition>;
/// The specified value of an `auto | <position>`.
pub type PositionOrAuto = GenericPositionOrAuto<Position>;
/// The specified value of a horizontal position.
pub type HorizontalPosition = PositionComponent<HorizontalPositionKeyword>;
/// The specified value of a vertical position.
pub type VerticalPosition = PositionComponent<VerticalPositionKeyword>;
/// The specified value of a component of a CSS `<position>`.
#[derive(Clone, Debug, MallocSizeOf, PartialEq, SpecifiedValueInfo, ToCss, ToShmem)]
pub enum PositionComponent<S> {
/// `center`
Center,
/// `<length-percentage>`
Length(LengthPercentage),
/// `<side> <length-percentage>?`
Side(S, Option<LengthPercentage>),
}
/// A keyword for the X direction.
#[derive(
Clone,
Copy,
Debug,
Eq,
Hash,
MallocSizeOf,
Parse,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
#[allow(missing_docs)]
#[repr(u8)]
pub enum HorizontalPositionKeyword {
Left,
Right,
}
/// A keyword for the Y direction.
#[derive(
Clone,
Copy,
Debug,
Eq,
Hash,
MallocSizeOf,
Parse,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
#[allow(missing_docs)]
#[repr(u8)]
pub enum VerticalPositionKeyword {
Top,
Bottom,
}
impl Parse for Position {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
let position = Self::parse_three_value_quirky(context, input, AllowQuirks::No)?;
if position.is_three_value_syntax() {
return Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError));
}
Ok(position)
}
}
impl Position {
/// Parses a `<bg-position>`, with quirks.
pub fn parse_three_value_quirky<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
allow_quirks: AllowQuirks,
) -> Result<Self, ParseError<'i>> {
match input.try_parse(|i| PositionComponent::parse_quirky(context, i, allow_quirks)) {
Ok(x_pos @ PositionComponent::Center) => {
if let Ok(y_pos) =
input.try_parse(|i| PositionComponent::parse_quirky(context, i, allow_quirks))
{
return Ok(Self::new(x_pos, y_pos));
}
let x_pos = input
.try_parse(|i| PositionComponent::parse_quirky(context, i, allow_quirks))
.unwrap_or(x_pos);
let y_pos = PositionComponent::Center;
return Ok(Self::new(x_pos, y_pos));
},
Ok(PositionComponent::Side(x_keyword, lp)) => {
if input
.try_parse(|i| i.expect_ident_matching("center"))
.is_ok()
{
let x_pos = PositionComponent::Side(x_keyword, lp);
let y_pos = PositionComponent::Center;
return Ok(Self::new(x_pos, y_pos));
}
if let Ok(y_keyword) = input.try_parse(VerticalPositionKeyword::parse) {
let y_lp = input
.try_parse(|i| LengthPercentage::parse_quirky(context, i, allow_quirks))
.ok();
let x_pos = PositionComponent::Side(x_keyword, lp);
let y_pos = PositionComponent::Side(y_keyword, y_lp);
return Ok(Self::new(x_pos, y_pos));
}
let x_pos = PositionComponent::Side(x_keyword, None);
let y_pos = lp.map_or(PositionComponent::Center, PositionComponent::Length);
return Ok(Self::new(x_pos, y_pos));
},
Ok(x_pos @ PositionComponent::Length(_)) => {
if let Ok(y_keyword) = input.try_parse(VerticalPositionKeyword::parse) {
let y_pos = PositionComponent::Side(y_keyword, None);
return Ok(Self::new(x_pos, y_pos));
}
if let Ok(y_lp) =
input.try_parse(|i| LengthPercentage::parse_quirky(context, i, allow_quirks))
{
let y_pos = PositionComponent::Length(y_lp);
return Ok(Self::new(x_pos, y_pos));
}
let y_pos = PositionComponent::Center;
let _ = input.try_parse(|i| i.expect_ident_matching("center"));
return Ok(Self::new(x_pos, y_pos));
},
Err(_) => {},
}
let y_keyword = VerticalPositionKeyword::parse(input)?;
let lp_and_x_pos: Result<_, ParseError> = input.try_parse(|i| {
let y_lp = i
.try_parse(|i| LengthPercentage::parse_quirky(context, i, allow_quirks))
.ok();
if let Ok(x_keyword) = i.try_parse(HorizontalPositionKeyword::parse) {
let x_lp = i
.try_parse(|i| LengthPercentage::parse_quirky(context, i, allow_quirks))
.ok();
let x_pos = PositionComponent::Side(x_keyword, x_lp);
return Ok((y_lp, x_pos));
};
i.expect_ident_matching("center")?;
let x_pos = PositionComponent::Center;
Ok((y_lp, x_pos))
});
if let Ok((y_lp, x_pos)) = lp_and_x_pos {
let y_pos = PositionComponent::Side(y_keyword, y_lp);
return Ok(Self::new(x_pos, y_pos));
}
let x_pos = PositionComponent::Center;
let y_pos = PositionComponent::Side(y_keyword, None);
Ok(Self::new(x_pos, y_pos))
}
/// `center center`
#[inline]
pub fn center() -> Self {
Self::new(PositionComponent::Center, PositionComponent::Center)
}
/// Returns true if this uses a 3 value syntax.
#[inline]
fn is_three_value_syntax(&self) -> bool {
self.horizontal.component_count() != self.vertical.component_count()
}
}
impl ToCss for Position {
fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
where
W: Write,
{
match (&self.horizontal, &self.vertical) {
(
x_pos @ &PositionComponent::Side(_, Some(_)),
&PositionComponent::Length(ref y_lp),
) => {
x_pos.to_css(dest)?;
dest.write_str(" top ")?;
y_lp.to_css(dest)
},
(
&PositionComponent::Length(ref x_lp),
y_pos @ &PositionComponent::Side(_, Some(_)),
) => {
dest.write_str("left ")?;
x_lp.to_css(dest)?;
dest.write_char(' ')?;
y_pos.to_css(dest)
},
(x_pos, y_pos) => {
x_pos.to_css(dest)?;
dest.write_char(' ')?;
y_pos.to_css(dest)
},
}
}
}
impl<S: Parse> Parse for PositionComponent<S> {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
Self::parse_quirky(context, input, AllowQuirks::No)
}
}
impl<S: Parse> PositionComponent<S> {
/// Parses a component of a CSS position, with quirks.
pub fn parse_quirky<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
allow_quirks: AllowQuirks,
) -> Result<Self, ParseError<'i>> {
if input
.try_parse(|i| i.expect_ident_matching("center"))
.is_ok()
{
return Ok(PositionComponent::Center);
}
if let Ok(lp) =
input.try_parse(|i| LengthPercentage::parse_quirky(context, i, allow_quirks))
{
return Ok(PositionComponent::Length(lp));
}
let keyword = S::parse(context, input)?;
let lp = input
.try_parse(|i| LengthPercentage::parse_quirky(context, i, allow_quirks))
.ok();
Ok(PositionComponent::Side(keyword, lp))
}
}
impl<S> GenericPositionComponent for PositionComponent<S> {
fn is_center(&self) -> bool {
match *self {
PositionComponent::Center => true,
PositionComponent::Length(LengthPercentage::Percentage(ref per)) => per.0 == 0.5,
// 50% from any side is still the center.
PositionComponent::Side(_, Some(LengthPercentage::Percentage(ref per))) => per.0 == 0.5,
_ => false,
}
}
}
impl<S> PositionComponent<S> {
/// `0%`
pub fn zero() -> Self {
PositionComponent::Length(LengthPercentage::Percentage(Percentage::zero()))
}
/// Returns the count of this component.
fn component_count(&self) -> usize {
match *self {
PositionComponent::Length(..) | PositionComponent::Center => 1,
PositionComponent::Side(_, ref lp) => {
if lp.is_some() {
2
} else {
1
}
},
}
}
}
impl<S: Side> ToComputedValue for PositionComponent<S> {
type ComputedValue = ComputedLengthPercentage;
fn to_computed_value(&self, context: &Context) -> Self::ComputedValue {
match *self {
PositionComponent::Center => ComputedLengthPercentage::new_percent(Percentage(0.5)),
PositionComponent::Side(ref keyword, None) => {
let p = Percentage(if keyword.is_start() { 0. } else { 1. });
ComputedLengthPercentage::new_percent(p)
},
PositionComponent::Side(ref keyword, Some(ref length)) if !keyword.is_start() => {
let length = length.to_computed_value(context);
// We represent `<end-side> <length>` as `calc(100% - <length>)`.
ComputedLengthPercentage::hundred_percent_minus(length, AllowedNumericType::All)
},
PositionComponent::Side(_, Some(ref length)) |
PositionComponent::Length(ref length) => length.to_computed_value(context),
}
}
fn from_computed_value(computed: &Self::ComputedValue) -> Self {
PositionComponent::Length(ToComputedValue::from_computed_value(computed))
}
}
impl<S: Side> PositionComponent<S> {
/// The initial specified value of a position component, i.e. the start side.
pub fn initial_specified_value() -> Self {
PositionComponent::Side(S::start(), None)
}
}
#[repr(transparent)]
#[derive(
Clone,
Debug,
MallocSizeOf,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
#[css(comma)]
pub struct AnchorName(
#[css(iterable, if_empty = "none")]
#[ignore_malloc_size_of = "Arc"]
pub crate::ArcSlice<DashedIdent>,
);
impl AnchorName {
/// Return the `none` value.
pub fn none() -> Self {
Self(Default::default())
}
/// Returns whether this is the `none` value.
pub fn is_none(&self) -> bool {
self.0.is_empty()
}
}
impl Parse for AnchorName {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
let location = input.current_source_location();
let first = input.expect_ident()?;
if first.eq_ignore_ascii_case("none") {
return Ok(Self::none());
}
// The common case is probably just to have a single anchor name, so
// space for four on the stack should be plenty.
let mut idents: SmallVec<[DashedIdent; 4]> =
smallvec![DashedIdent::from_ident(location, first,)?];
while input.try_parse(|input| input.expect_comma()).is_ok() {
idents.push(DashedIdent::parse(context, input)?);
}
Ok(AnchorName(ArcSlice::from_iter(idents.drain(..))))
}
}
#[derive(
Clone,
Debug,
MallocSizeOf,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
#[repr(u8)]
pub enum AnchorScope {
/// `none`
None,
/// `all`
All,
/// `<dashed-ident>#`
#[css(comma)]
Idents(
#[css(iterable)]
#[ignore_malloc_size_of = "Arc"]
crate::ArcSlice<DashedIdent>,
),
}
impl AnchorScope {
/// Return the `none` value.
pub fn none() -> Self {
Self::None
}
/// Returns whether this is the `none` value.
pub fn is_none(&self) -> bool {
*self == Self::None
}
}
impl Parse for AnchorScope {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
let location = input.current_source_location();
let first = input.expect_ident()?;
if first.eq_ignore_ascii_case("none") {
return Ok(Self::None);
}
if first.eq_ignore_ascii_case("all") {
return Ok(Self::All);
}
// Authors using more than a handful of anchored elements is likely
// uncommon, so we only pre-allocate for 8 on the stack here.
let mut idents: SmallVec<[DashedIdent; 8]> =
smallvec![DashedIdent::from_ident(location, first,)?];
while input.try_parse(|input| input.expect_comma()).is_ok() {
idents.push(DashedIdent::parse(context, input)?);
}
Ok(AnchorScope::Idents(ArcSlice::from_iter(idents.drain(..))))
}
}
#[derive(
Clone,
Debug,
MallocSizeOf,
Parse,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
#[repr(u8)]
pub enum PositionAnchor {
/// `auto`
Auto,
/// `<dashed-ident>`
Ident(DashedIdent),
}
impl PositionAnchor {
/// Return the `auto` value.
pub fn auto() -> Self {
Self::Auto
}
/// Returns whether this is the `auto` value.
pub fn is_auto(&self) -> bool {
*self == Self::Auto
}
}
#[derive(
Clone,
Copy,
Debug,
Default,
Eq,
MallocSizeOf,
Parse,
PartialEq,
Serialize,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
#[repr(u8)]
/// How to swap values for the automatically-generated position tactic.
pub enum PositionTryFallbacksTryTacticKeyword {
/// Magic value for no change.
#[css(skip)]
#[default]
None,
/// Swap the values in the block axis.
FlipBlock,
/// Swap the values in the inline axis.
FlipInline,
/// Swap the values in the start properties.
FlipStart,
}
impl PositionTryFallbacksTryTacticKeyword {
fn is_none(&self) -> bool {
*self == Self::None
}
}
#[derive(
Clone,
Copy,
Debug,
Default,
Eq,
MallocSizeOf,
PartialEq,
Serialize,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
#[repr(C)]
/// Changes for the automatically-generated position option.
/// Note that this is order-dependent - e.g. `flip-start flip-inline` != `flip-inline flip-start`.
///
pub struct PositionTryFallbacksTryTactic(
pub PositionTryFallbacksTryTacticKeyword,
pub PositionTryFallbacksTryTacticKeyword,
pub PositionTryFallbacksTryTacticKeyword,
);
impl Parse for PositionTryFallbacksTryTactic {
fn parse<'i, 't>(
_context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
let first = input.try_parse(PositionTryFallbacksTryTacticKeyword::parse)?;
let second = input.try_parse(PositionTryFallbacksTryTacticKeyword::parse).unwrap_or_default();
let third = input.try_parse(PositionTryFallbacksTryTacticKeyword::parse).unwrap_or_default();
if first == second || first == third || (!second.is_none() && second == third) {
return Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError));
}
Ok(Self(first, second, third))
}
}
impl PositionTryFallbacksTryTactic {
fn is_empty(&self) -> bool {
self.0.is_none()
}
}
#[derive(
Clone,
Debug,
MallocSizeOf,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
#[repr(C)]
/// <dashed-ident> || <try-tactic>
pub struct DashedIdentAndOrTryTactic {
/// `<dashed-ident>`
pub ident: DashedIdent,
/// `<try-tactic>`
pub try_tactic: PositionTryFallbacksTryTactic,
}
impl Parse for DashedIdentAndOrTryTactic {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
let mut result = Self {
ident: DashedIdent::empty(),
try_tactic: PositionTryFallbacksTryTactic::default(),
};
loop {
if result.ident.is_empty() {
if let Ok(ident) = input.try_parse(|i| DashedIdent::parse(context, i)) {
result.ident = ident;
continue;
}
}
if result.try_tactic.is_empty() {
if let Ok(try_tactic) =
input.try_parse(|i| PositionTryFallbacksTryTactic::parse(context, i))
{
result.try_tactic = try_tactic;
continue;
}
}
break;
}
if result.ident.is_empty() && result.try_tactic.is_empty() {
return Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError));
}
return Ok(result);
}
}
#[derive(
Clone,
Debug,
MallocSizeOf,
Parse,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
#[repr(u8)]
/// [ [<dashed-ident> || <try-tactic>] | <'position-area'> ]
pub enum PositionTryFallbacksItem {
/// `<dashed-ident> || <try-tactic>`
IdentAndOrTactic(DashedIdentAndOrTryTactic),
#[parse(parse_fn = "PositionArea::parse_except_none")]
/// `<position-area>`
PositionArea(PositionArea),
}
#[derive(
Clone,
Debug,
Default,
MallocSizeOf,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
#[css(comma)]
#[repr(C)]
pub struct PositionTryFallbacks(
#[css(iterable, if_empty = "none")]
#[ignore_malloc_size_of = "Arc"]
pub crate::ArcSlice<PositionTryFallbacksItem>,
);
impl PositionTryFallbacks {
#[inline]
/// Return the `none` value.
pub fn none() -> Self {
Self(Default::default())
}
/// Returns whether this is the `none` value.
pub fn is_none(&self) -> bool {
self.0.is_empty()
}
}
impl Parse for PositionTryFallbacks {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
if input.try_parse(|i| i.expect_ident_matching("none")).is_ok() {
return Ok(Self::none());
}
// The common case is unlikely to include many alternate positioning
// styles, so space for four on the stack should typically be enough.
let mut items: SmallVec<[PositionTryFallbacksItem; 4]> =
smallvec![PositionTryFallbacksItem::parse(context, input)?];
while input.try_parse(|input| input.expect_comma()).is_ok() {
items.push(PositionTryFallbacksItem::parse(context, input)?);
}
Ok(Self(ArcSlice::from_iter(items.drain(..))))
}
}
#[derive(
Clone,
Copy,
Debug,
Default,
Eq,
MallocSizeOf,
Parse,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
#[repr(u8)]
pub enum PositionTryOrder {
#[default]
/// `normal`
Normal,
/// `most-width`
MostWidth,
/// `most-height`
MostHeight,
/// `most-block-size`
MostBlockSize,
/// `most-inline-size`
MostInlineSize,
}
impl PositionTryOrder {
#[inline]
/// Return the `auto` value.
pub fn normal() -> Self {
Self::Normal
}
/// Returns whether this is the `auto` value.
pub fn is_normal(&self) -> bool {
*self == Self::Normal
}
}
#[derive(
Clone,
Copy,
Debug,
Eq,
MallocSizeOf,
Parse,
PartialEq,
Serialize,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
#[css(bitflags(single = "always", mixed = "anchors-valid,anchors-visible,no-overflow"))]
#[repr(C)]
/// Specified keyword values for the position-visibility property.
pub struct PositionVisibility(u8);
bitflags! {
impl PositionVisibility: u8 {
/// Element is displayed without regard for its anchors or its overflowing status.
const ALWAYS = 0;
/// anchors-valid
const ANCHORS_VALID = 1 << 0;
/// anchors-visible
const ANCHORS_VISIBLE = 1 << 1;
/// no-overflow
const NO_OVERFLOW = 1 << 2;
}
}
impl Default for PositionVisibility {
fn default() -> Self {
Self::ALWAYS
}
}
impl PositionVisibility {
#[inline]
/// Returns the initial value of position-visibility
pub fn always() -> Self {
Self::ALWAYS
}
}
#[derive(
Clone,
Copy,
Debug,
Default,
Eq,
MallocSizeOf,
Parse,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
#[allow(missing_docs)]
#[repr(u8)]
/// Possible values for the `position-area` preperty's keywords.
pub enum PositionAreaKeyword {
#[default]
None,
// Common (shared) keywords:
Center,
SpanAll,
// Horizontal keywords:
Left,
Right,
SpanLeft,
SpanRight,
XStart,
XEnd,
SpanXStart,
SpanXEnd,
XSelfStart,
XSelfEnd,
SpanXSelfStart,
SpanXSelfEnd,
// Vertical keywords:
Top,
Bottom,
SpanTop,
SpanBottom,
YStart,
YEnd,
SpanYStart,
SpanYEnd,
YSelfStart,
YSelfEnd,
SpanYSelfStart,
SpanYSelfEnd,
// Block keywords:
BlockStart,
BlockEnd,
SpanBlockStart,
SpanBlockEnd,
// Inline keywords:
InlineStart,
InlineEnd,
SpanInlineStart,
SpanInlineEnd,
// "Self" block keywords:
SelfBlockStart,
SelfBlockEnd,
SpanSelfBlockStart,
SpanSelfBlockEnd,
// "Self" inline keywords:
SelfInlineStart,
SelfInlineEnd,
SpanSelfInlineStart,
SpanSelfInlineEnd,
// Inferred axis keywords:
Start,
End,
SpanStart,
SpanEnd,
// "Self" inferred axis keywords:
SelfStart,
SelfEnd,
SpanSelfStart,
SpanSelfEnd,
}
#[allow(missing_docs)]
impl PositionAreaKeyword {
#[inline]
pub fn none() -> Self {
Self::None
}
pub fn is_none(&self) -> bool {
*self == Self::None
}
/// Is a value that's common to all compatible keyword groupings.
pub fn is_common(&self) -> bool {
*self == Self::Center || *self == Self::SpanAll
}
pub fn is_horizontal(&self) -> bool {
matches!(
self,
Self::Left |
Self::Right |
Self::SpanLeft |
Self::SpanRight |
Self::XStart |
Self::XEnd |
Self::SpanXStart |
Self::SpanXEnd |
Self::XSelfStart |
Self::XSelfEnd |
Self::SpanXSelfStart |
Self::SpanXSelfEnd
)
}
pub fn is_vertical(&self) -> bool {
matches!(
self,
Self::Top |
Self::Bottom |
Self::SpanTop |
Self::SpanBottom |
Self::YStart |
Self::YEnd |
Self::SpanYStart |
Self::SpanYEnd |
Self::YSelfStart |
Self::YSelfEnd |
Self::SpanYSelfStart |
Self::SpanYSelfEnd
)
}
pub fn is_block(&self) -> bool {
matches!(
self,
Self::BlockStart | Self::BlockEnd | Self::SpanBlockStart | Self::SpanBlockEnd
)
}
pub fn is_inline(&self) -> bool {
matches!(
self,
Self::InlineStart | Self::InlineEnd | Self::SpanInlineStart | Self::SpanInlineEnd
)
}
pub fn is_self_block(&self) -> bool {
matches!(
self,
Self::SelfBlockStart |
Self::SelfBlockEnd |
Self::SpanSelfBlockStart |
Self::SpanSelfBlockEnd
)
}
pub fn is_self_inline(&self) -> bool {
matches!(
self,
Self::SelfInlineStart |
Self::SelfInlineEnd |
Self::SpanSelfInlineStart |
Self::SpanSelfInlineEnd
)
}
pub fn is_inferred_logical(&self) -> bool {
matches!(
self,
Self::Start | Self::End | Self::SpanStart | Self::SpanEnd
)
}
pub fn is_self_inferred_logical(&self) -> bool {
matches!(
self,
Self::SelfStart | Self::SelfEnd | Self::SpanSelfStart | Self::SpanSelfEnd
)
}
}
#[inline]
fn is_compatible_pairing(first: PositionAreaKeyword, second: PositionAreaKeyword) -> bool {
if first.is_none() || second.is_none() {
// `none` is not allowed as one of the keywords when two keywords are
// provided.
return false;
}
if first.is_common() || second.is_common() {
return true;
}
if first.is_horizontal() {
return second.is_vertical();
}
if first.is_vertical() {
return second.is_horizontal();
}
if first.is_block() {
return second.is_inline();
}
if first.is_inline() {
return second.is_block();
}
if first.is_self_block() {
return second.is_self_inline();
}
if first.is_self_inline() {
return second.is_self_block();
}
if first.is_inferred_logical() {
return second.is_inferred_logical();
}
if first.is_self_inferred_logical() {
return second.is_self_inferred_logical();
}
debug_assert!(false, "Not reached");
// Return false to increase the chances of this being reported to us if we
// ever were to get here.
false
}
#[derive(
Clone,
Copy,
Debug,
Eq,
MallocSizeOf,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
#[repr(C)]
pub struct PositionArea {
/// First keyword, if any.
pub first: PositionAreaKeyword,
/// Second keyword, if any.
#[css(skip_if = "PositionAreaKeyword::is_none")]
pub second: PositionAreaKeyword,
}
#[allow(missing_docs)]
impl PositionArea {
#[inline]
pub fn none() -> Self {
Self {
first: PositionAreaKeyword::None,
second: PositionAreaKeyword::None,
}
}
#[inline]
pub fn is_none(&self) -> bool {
self.first.is_none()
}
pub fn parse_except_none<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
Self::parse_internal(context, input, /*allow_none*/ false)
}
fn parse_internal<'i, 't>(
_context: &ParserContext,
input: &mut Parser<'i, 't>,
allow_none: bool,
) -> Result<Self, ParseError<'i>> {
let mut location = input.current_source_location();
let mut first = PositionAreaKeyword::parse(input)?;
if first.is_none() {
if allow_none {
return Ok(Self::none());
}
return Err(location.new_custom_error(StyleParseErrorKind::UnspecifiedError));
}
location = input.current_source_location();
let second = input.try_parse(PositionAreaKeyword::parse);
if let Ok(PositionAreaKeyword::None) = second {
// `none` is only allowed as a single value
return Err(location.new_custom_error(StyleParseErrorKind::UnspecifiedError));
}
let mut second = second.unwrap_or(PositionAreaKeyword::None);
if second.is_none() {
// Either there was no second keyword and try_parse returned a
// BasicParseErrorKind::EndOfInput, or else the second "keyword"
// was invalid. We assume the former case here, and if it's the
// latter case then our caller detects the error (try_parse will,
// have rewound, leaving an unparsed token).
return Ok(Self { first, second });
}
if !is_compatible_pairing(first, second) {
return Err(location.new_custom_error(StyleParseErrorKind::UnspecifiedError));
}
// Normalize by applying the shortest serialization principle:
if first.is_inferred_logical() ||
second.is_inferred_logical() ||
first.is_self_inferred_logical() ||
second.is_self_inferred_logical() ||
(first.is_common() && second.is_common())
{
// In these cases we must not change the order of the keywords
// since their meaning is inferred from their order. However, if
// both keywords are the same, only one should be set.
if first == second {
second = PositionAreaKeyword::None;
}
} else if second == PositionAreaKeyword::SpanAll {
// Span-all is the default behavior, so specifying `span-all` is
// superfluous.
second = PositionAreaKeyword::None;
} else if first == PositionAreaKeyword::SpanAll {
// Same here, but the non-superfluous keyword must come first.
first = second;
second = PositionAreaKeyword::None;
} else if first.is_vertical() ||
second.is_horizontal() ||
first.is_inline() ||
second.is_block() ||
first.is_self_inline() ||
second.is_self_block()
{
// Canonical order is horizontal before vertical, block before inline.
std::mem::swap(&mut first, &mut second);
}
Ok(Self { first, second })
}
}
impl Parse for PositionArea {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
Self::parse_internal(context, input, /*allow_none*/ true)
}
}
/// Represents a side, either horizontal or vertical, of a CSS position.
pub trait Side {
/// Returns the start side.
fn start() -> Self;
/// Returns whether this side is the start side.
fn is_start(&self) -> bool;
}
impl Side for HorizontalPositionKeyword {
#[inline]
fn start() -> Self {
HorizontalPositionKeyword::Left
}
#[inline]
fn is_start(&self) -> bool {
*self == Self::start()
}
}
impl Side for VerticalPositionKeyword {
#[inline]
fn start() -> Self {
VerticalPositionKeyword::Top
}
#[inline]
fn is_start(&self) -> bool {
*self == Self::start()
}
}
/// Controls how the auto-placement algorithm works specifying exactly how auto-placed items
/// get flowed into the grid: [ row | column ] || dense
#[derive(
Clone,
Copy,
Debug,
Eq,
MallocSizeOf,
Parse,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToResolvedValue,
ToShmem,
)]
#[css(bitflags(
mixed = "row,column,dense",
validate_mixed = "Self::validate_and_simplify"
))]
#[repr(C)]
pub struct GridAutoFlow(u8);
bitflags! {
impl GridAutoFlow: u8 {
/// 'row' - mutually exclusive with 'column'
const ROW = 1 << 0;
/// 'column' - mutually exclusive with 'row'
const COLUMN = 1 << 1;
/// 'dense'
const DENSE = 1 << 2;
}
}
impl GridAutoFlow {
/// [ row | column ] || dense
fn validate_and_simplify(&mut self) -> bool {
if self.contains(Self::ROW | Self::COLUMN) {
// row and column are mutually exclusive.
return false;
}
if *self == Self::DENSE {
// If there's no column, default to row.
self.insert(Self::ROW);
}
true
}
}
impl ToCss for GridAutoFlow {
fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
where
W: Write,
{
let dense = self.intersects(Self::DENSE);
if self.intersects(Self::ROW) {
return if dense {
dest.write_str("dense")
} else {
dest.write_str("row")
};
}
debug_assert!(self.intersects(Self::COLUMN));
if dense {
dest.write_str("column dense")
} else {
dest.write_str("column")
}
}
}
#[repr(u8)]
#[derive(
Clone,
Copy,
Debug,
Eq,
MallocSizeOf,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
/// Masonry auto-placement algorithm packing.
pub enum MasonryPlacement {
/// Place the item in the track(s) with the smallest extent so far.
Pack,
/// Place the item after the last item, from start to end.
Next,
}
#[repr(u8)]
#[derive(
Clone,
Copy,
Debug,
Eq,
MallocSizeOf,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
/// Masonry auto-placement algorithm item sorting option.
pub enum MasonryItemOrder {
/// Place all items with a definite placement before auto-placed items.
DefiniteFirst,
/// Place items in `order-modified document order`.
Ordered,
}
#[derive(
Clone,
Copy,
Debug,
Eq,
MallocSizeOf,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
#[repr(C)]
/// Controls how the Masonry layout algorithm works
/// specifying exactly how auto-placed items get flowed in the masonry axis.
pub struct MasonryAutoFlow {
/// Specify how to pick a auto-placement track.
#[css(contextual_skip_if = "is_pack_with_non_default_order")]
pub placement: MasonryPlacement,
/// Specify how to pick an item to place.
#[css(skip_if = "is_item_order_definite_first")]
pub order: MasonryItemOrder,
}
#[inline]
fn is_pack_with_non_default_order(placement: &MasonryPlacement, order: &MasonryItemOrder) -> bool {
*placement == MasonryPlacement::Pack && *order != MasonryItemOrder::DefiniteFirst
}
#[inline]
fn is_item_order_definite_first(order: &MasonryItemOrder) -> bool {
*order == MasonryItemOrder::DefiniteFirst
}
impl MasonryAutoFlow {
#[inline]
/// Get initial `masonry-auto-flow` value.
pub fn initial() -> MasonryAutoFlow {
MasonryAutoFlow {
placement: MasonryPlacement::Pack,
order: MasonryItemOrder::DefiniteFirst,
}
}
}
impl Parse for MasonryAutoFlow {
/// [ definite-first | ordered ] || [ pack | next ]
fn parse<'i, 't>(
_context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<MasonryAutoFlow, ParseError<'i>> {
let mut value = MasonryAutoFlow::initial();
let mut got_placement = false;
let mut got_order = false;
while !input.is_exhausted() {
let location = input.current_source_location();
let ident = input.expect_ident()?;
let success = match_ignore_ascii_case! { &ident,
"pack" if !got_placement => {
got_placement = true;
true
},
"next" if !got_placement => {
value.placement = MasonryPlacement::Next;
got_placement = true;
true
},
"definite-first" if !got_order => {
got_order = true;
true
},
"ordered" if !got_order => {
value.order = MasonryItemOrder::Ordered;
got_order = true;
true
},
_ => false
};
if !success {
return Err(location
.new_custom_error(SelectorParseErrorKind::UnexpectedIdent(ident.clone())));
}
}
if got_placement || got_order {
Ok(value)
} else {
Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError))
}
}
}
#[derive(
Clone,
Debug,
MallocSizeOf,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
#[repr(C)]
pub struct TemplateAreas {
/// `named area` containing for each template area
#[css(skip)]
pub areas: crate::OwnedSlice<NamedArea>,
/// The simplified CSS strings for serialization purpose.
// Note: We also use the length of `strings` when computing the explicit grid end line number
// (i.e. row number).
#[css(iterable)]
pub strings: crate::OwnedSlice<crate::OwnedStr>,
/// The number of columns of the grid.
#[css(skip)]
pub width: u32,
}
/// Parser for grid template areas.
#[derive(Default)]
pub struct TemplateAreasParser {
areas: Vec<NamedArea>,
area_indices: PrecomputedHashMap<Atom, usize>,
strings: Vec<crate::OwnedStr>,
width: u32,
row: u32,
}
impl TemplateAreasParser {
/// Parse a single string.
pub fn try_parse_string<'i>(
&mut self,
input: &mut Parser<'i, '_>,
) -> Result<(), ParseError<'i>> {
input.try_parse(|input| {
self.parse_string(input.expect_string()?)
.map_err(|()| input.new_custom_error(StyleParseErrorKind::UnspecifiedError))
})
}
/// Parse a single string.
fn parse_string(&mut self, string: &str) -> Result<(), ()> {
self.row += 1;
let mut simplified_string = String::new();
let mut current_area_index: Option<usize> = None;
let mut column = 0u32;
for token in TemplateAreasTokenizer(string) {
column += 1;
if column > 1 {
simplified_string.push(' ');
}
let name = if let Some(token) = token? {
simplified_string.push_str(token);
Atom::from(token)
} else {
if let Some(index) = current_area_index.take() {
if self.areas[index].columns.end != column {
return Err(());
}
}
simplified_string.push('.');
continue;
};
if let Some(index) = current_area_index {
if self.areas[index].name == name {
if self.areas[index].rows.start == self.row {
self.areas[index].columns.end += 1;
}
continue;
}
if self.areas[index].columns.end != column {
return Err(());
}
}
match self.area_indices.entry(name) {
Entry::Occupied(ref e) => {
let index = *e.get();
if self.areas[index].columns.start != column ||
self.areas[index].rows.end != self.row
{
return Err(());
}
self.areas[index].rows.end += 1;
current_area_index = Some(index);
},
Entry::Vacant(v) => {
let index = self.areas.len();
let name = v.key().clone();
v.insert(index);
self.areas.push(NamedArea {
name,
columns: UnsignedRange {
start: column,
end: column + 1,
},
rows: UnsignedRange {
start: self.row,
end: self.row + 1,
},
});
current_area_index = Some(index);
},
}
}
if column == 0 {
// Each string must produce a valid token.
return Err(());
}
if let Some(index) = current_area_index {
if self.areas[index].columns.end != column + 1 {
debug_assert_ne!(self.areas[index].rows.start, self.row);
return Err(());
}
}
if self.row == 1 {
self.width = column;
} else if self.width != column {
return Err(());
}
self.strings.push(simplified_string.into());
Ok(())
}
/// Return the parsed template areas.
pub fn finish(self) -> Result<TemplateAreas, ()> {
if self.strings.is_empty() {
return Err(());
}
Ok(TemplateAreas {
areas: self.areas.into(),
strings: self.strings.into(),
width: self.width,
})
}
}
impl TemplateAreas {
fn parse_internal(input: &mut Parser) -> Result<Self, ()> {
let mut parser = TemplateAreasParser::default();
while parser.try_parse_string(input).is_ok() {}
parser.finish()
}
}
impl Parse for TemplateAreas {
fn parse<'i, 't>(
_: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
Self::parse_internal(input)
.map_err(|()| input.new_custom_error(StyleParseErrorKind::UnspecifiedError))
}
}
/// Arc type for `Arc<TemplateAreas>`
#[derive(
Clone,
Debug,
MallocSizeOf,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
#[repr(transparent)]
pub struct TemplateAreasArc(#[ignore_malloc_size_of = "Arc"] pub Arc<TemplateAreas>);
impl Parse for TemplateAreasArc {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
let parsed = TemplateAreas::parse(context, input)?;
Ok(TemplateAreasArc(Arc::new(parsed)))
}
}
/// A range of rows or columns. Using this instead of std::ops::Range for FFI
/// purposes.
#[repr(C)]
#[derive(
Clone,
Debug,
MallocSizeOf,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToResolvedValue,
ToShmem,
)]
pub struct UnsignedRange {
/// The start of the range.
pub start: u32,
/// The end of the range.
pub end: u32,
}
#[derive(
Clone,
Debug,
MallocSizeOf,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToResolvedValue,
ToShmem,
)]
#[repr(C)]
/// Not associated with any particular grid item, but can be referenced from the
/// grid-placement properties.
pub struct NamedArea {
/// Name of the `named area`
pub name: Atom,
/// Rows of the `named area`
pub rows: UnsignedRange,
/// Columns of the `named area`
pub columns: UnsignedRange,
}
/// Tokenize the string into a list of the tokens,
/// using longest-match semantics
struct TemplateAreasTokenizer<'a>(&'a str);
impl<'a> Iterator for TemplateAreasTokenizer<'a> {
type Item = Result<Option<&'a str>, ()>;
fn next(&mut self) -> Option<Self::Item> {
let rest = self.0.trim_start_matches(HTML_SPACE_CHARACTERS);
if rest.is_empty() {
return None;
}
if rest.starts_with('.') {
self.0 = &rest[rest.find(|c| c != '.').unwrap_or(rest.len())..];
return Some(Ok(None));
}
if !rest.starts_with(is_name_code_point) {
return Some(Err(()));
}
let token_len = rest.find(|c| !is_name_code_point(c)).unwrap_or(rest.len());
let token = &rest[..token_len];
self.0 = &rest[token_len..];
Some(Ok(Some(token)))
}
}
fn is_name_code_point(c: char) -> bool {
c >= 'A' && c <= 'Z' ||
c >= 'a' && c <= 'z' ||
c >= '\u{80}' ||
c == '_' ||
c >= '0' && c <= '9' ||
c == '-'
}
/// This property specifies named grid areas.
///
/// The syntax of this property also provides a visualization of the structure
/// of the grid, making the overall layout of the grid container easier to
/// understand.
#[repr(C, u8)]
#[derive(
Clone,
Debug,
MallocSizeOf,
Parse,
PartialEq,
SpecifiedValueInfo,
ToComputedValue,
ToCss,
ToResolvedValue,
ToShmem,
)]
pub enum GridTemplateAreas {
/// The `none` value.
None,
/// The actual value.
Areas(TemplateAreasArc),
}
impl GridTemplateAreas {
#[inline]
/// Get default value as `none`
pub fn none() -> GridTemplateAreas {
GridTemplateAreas::None
}
}
/// A specified value for the `z-index` property.
pub type ZIndex = GenericZIndex<Integer>;
/// A specified value for the `aspect-ratio` property.
pub type AspectRatio = GenericAspectRatio<NonNegativeNumber>;
impl Parse for AspectRatio {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
use crate::values::generics::position::PreferredRatio;
use crate::values::specified::Ratio;
let location = input.current_source_location();
let mut auto = input.try_parse(|i| i.expect_ident_matching("auto"));
let ratio = input.try_parse(|i| Ratio::parse(context, i));
if auto.is_err() {
auto = input.try_parse(|i| i.expect_ident_matching("auto"));
}
if auto.is_err() && ratio.is_err() {
return Err(location.new_custom_error(StyleParseErrorKind::UnspecifiedError));
}
Ok(AspectRatio {
auto: auto.is_ok(),
ratio: match ratio {
Ok(ratio) => PreferredRatio::Ratio(ratio),
Err(..) => PreferredRatio::None,
},
})
}
}
impl AspectRatio {
/// Returns Self by a valid ratio.
pub fn from_mapped_ratio(w: f32, h: f32) -> Self {
use crate::values::generics::position::PreferredRatio;
use crate::values::generics::ratio::Ratio;
AspectRatio {
auto: true,
ratio: PreferredRatio::Ratio(Ratio(
NonNegativeNumber::new(w),
NonNegativeNumber::new(h),
)),
}
}
}
/// A specified value for inset types.
pub type Inset = GenericInset<specified::Percentage, LengthPercentage>;
impl Inset {
/// Parses an inset type, allowing the unitless length quirk.
#[inline]
pub fn parse_quirky<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
allow_quirks: AllowQuirks,
) -> Result<Self, ParseError<'i>> {
if let Ok(l) = input.try_parse(|i| LengthPercentage::parse_quirky(context, i, allow_quirks))
{
return Ok(Self::LengthPercentage(l));
}
if input.try_parse(|i| i.expect_ident_matching("auto")).is_ok() {
return Ok(Self::Auto);
}
if let Ok(inner) = input.try_parse(|i| AnchorFunction::parse(context, i)) {
return Ok(Self::AnchorFunction(Box::new(inner)));
}
Ok(Self::AnchorSizeFunction(Box::new(
specified::AnchorSizeFunction::parse(context, input)?,
)))
}
}
impl Parse for Inset {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
Self::parse_quirky(context, input, AllowQuirks::No)
}
}
/// A specified value for `anchor()` function.
pub type AnchorFunction = GenericAnchorFunction<specified::Percentage, LengthPercentage>;
impl Parse for AnchorFunction {
fn parse<'i, 't>(
context: &ParserContext,
input: &mut Parser<'i, 't>,
) -> Result<Self, ParseError<'i>> {
if !static_prefs::pref!("layout.css.anchor-positioning.enabled") {
return Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError));
}
input.expect_function_matching("anchor")?;
input.parse_nested_block(|i| {
let target_element = i.try_parse(|i| DashedIdent::parse(context, i)).ok();
let side = AnchorSide::parse(context, i)?;
let target_element = if target_element.is_none() {
i.try_parse(|i| DashedIdent::parse(context, i)).ok()
} else {
target_element
};
let fallback = i
.try_parse(|i| {
i.expect_comma()?;
LengthPercentage::parse(context, i)
})
.ok();
Ok(Self {
target_element: target_element.unwrap_or_else(DashedIdent::empty),
side,
fallback: fallback.into(),
})
})
}
}