Mirrors/servo
1
0
Fork 0
mirror of https://github.com/servo/servo.git synced 2025-08-07 06:25:32 +01:00
Code Issues Projects Releases Packages Wiki Activity

Refactor grid style types and impls

Browse source 
Fixes #16949.
This commit is contained in:
Malo Jaffré 2017-05-21 20:46:45 +02:00
parent 0566c60157
commit 72db1765d0
7 changed files with 572 additions and 552 deletions
Download patch file Download diff file Expand all files Collapse all files

551
components/style/values/specified/grid.rs
View file

@ -2,157 +2,19 @@
* 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/. */
//! Necessary types for [grid](https://drafts.csswg.org/css-grid/).
//! CSS handling for the computed value of
//! [grids](https://drafts.csswg.org/css-grid/)
use cssparser::{Parser, Token, serialize_identifier};
use cssparser::{Parser, Token};
use parser::{Parse, ParserContext};
use std::{fmt, mem, usize};
use std::{mem, usize};
use std::ascii::AsciiExt;
use style_traits::{HasViewportPercentage, ToCss};
use style_traits::HasViewportPercentage;
use values::{CSSFloat, CustomIdent, Either};
use values::computed::{self, ComputedValueAsSpecified, Context, ToComputedValue};
use values::specified::{Integer, LengthOrPercentage};
#[derive(PartialEq, Clone, Debug)]
#[cfg_attr(feature = "servo", derive(HeapSizeOf))]
/// A `<grid-line>` type.
///
/// https://drafts.csswg.org/css-grid/#typedef-grid-row-start-grid-line
pub struct GridLine {
/// Flag to check whether it's a `span` keyword.
pub is_span: bool,
/// A custom identifier for named lines.
///
/// https://drafts.csswg.org/css-grid/#grid-placement-slot
pub ident: Option<String>,
/// Denotes the nth grid line from grid item's placement.
pub line_num: Option<Integer>,
}
impl GridLine {
/// Check whether this `<grid-line>` represents an `auto` value.
pub fn is_auto(&self) -> bool {
self.ident.is_none() && self.line_num.is_none() && !self.is_span
}
}
impl Default for GridLine {
fn default() -> Self {
GridLine {
is_span: false,
ident: None,
line_num: None,
}
}
}
impl ToCss for GridLine {
fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
if self.is_auto() {
return dest.write_str("auto")
}
if self.is_span {
dest.write_str("span")?;
}
if let Some(i) = self.line_num {
write!(dest, " {}", i.value)?;
}
if let Some(ref s) = self.ident {
dest.write_str(" ")?;
serialize_identifier(s, dest)?;
}
Ok(())
}
}
impl Parse for GridLine {
fn parse(context: &ParserContext, input: &mut Parser) -> Result<Self, ()> {
let mut grid_line = Default::default();
if input.try(|i| i.expect_ident_matching("auto")).is_ok() {
return Ok(grid_line)
}
for _ in 0..3 { // Maximum possible entities for <grid-line>
if input.try(|i| i.expect_ident_matching("span")).is_ok() {
if grid_line.is_span || grid_line.line_num.is_some() || grid_line.ident.is_some() {
return Err(()) // span (if specified) should be first
}
grid_line.is_span = true; // span (if specified) should be first
} else if let Ok(i) = input.try(|i| Integer::parse(context, i)) {
if i.value == 0 || grid_line.line_num.is_some() {
return Err(())
}
grid_line.line_num = Some(i);
} else if let Ok(name) = input.try(|i| i.expect_ident()) {
if grid_line.ident.is_some() || CustomIdent::from_ident((&*name).into(), &[]).is_err() {
return Err(())
}
grid_line.ident = Some(name.into_owned());
} else {
break
}
}
if grid_line.is_auto() {
return Err(())
}
if grid_line.is_span {
if let Some(i) = grid_line.line_num {
if i.value <= 0 { // disallow negative integers for grid spans
return Err(())
}
} else if grid_line.ident.is_some() { // integer could be omitted
grid_line.line_num = Some(Integer::new(1));
} else {
return Err(())
}
}
Ok(grid_line)
}
}
impl ComputedValueAsSpecified for GridLine {}
no_viewport_percentage!(GridLine);
define_css_keyword_enum!{ TrackKeyword:
"auto" => Auto,
"max-content" => MaxContent,
"min-content" => MinContent
}
#[derive(Clone, PartialEq, Debug)]
#[cfg_attr(feature = "servo", derive(HeapSizeOf))]
/// A track breadth for explicit grid track sizing. It's generic solely to
/// avoid re-implementing it for the computed type.
///
/// https://drafts.csswg.org/css-grid/#typedef-track-breadth
pub enum TrackBreadth<L> {
/// The generic type is almost always a non-negative `<length-percentage>`
Breadth(L),
/// A flex fraction specified in `fr` units.
Flex(CSSFloat),
/// One of the track-sizing keywords (`auto`, `min-content`, `max-content`)
Keyword(TrackKeyword),
}
impl<L> TrackBreadth<L> {
/// Check whether this is a `<fixed-breadth>` (i.e., it only has `<length-percentage>`)
///
/// https://drafts.csswg.org/css-grid/#typedef-fixed-breadth
#[inline]
pub fn is_fixed(&self) -> bool {
match *self {
TrackBreadth::Breadth(ref _lop) => true,
_ => false,
}
}
}
use values::computed::{self, Context, ToComputedValue};
use values::generics::grid::{RepeatCount, TrackBreadth, TrackKeyword, TrackRepeat};
use values::generics::grid::{TrackSize, TrackList, TrackListType};
use values::specified::LengthOrPercentage;
/// Parse a single flexible length.
pub fn parse_flex(input: &mut Parser) -> Result<CSSFloat, ()> {
@ -177,16 +39,6 @@ impl Parse for TrackBreadth<LengthOrPercentage> {
}
}
impl<L: ToCss> ToCss for TrackBreadth<L> {
fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
match *self {
TrackBreadth::Breadth(ref lop) => lop.to_css(dest),
TrackBreadth::Flex(ref value) => write!(dest, "{}fr", value),
TrackBreadth::Keyword(ref k) => k.to_css(dest),
}
}
}
impl HasViewportPercentage for TrackBreadth<LengthOrPercentage> {
#[inline]
fn has_viewport_percentage(&self) -> bool {
@ -198,81 +50,6 @@ impl HasViewportPercentage for TrackBreadth<LengthOrPercentage> {
}
}
impl<L: ToComputedValue> ToComputedValue for TrackBreadth<L> {
type ComputedValue = TrackBreadth<L::ComputedValue>;
#[inline]
fn to_computed_value(&self, context: &Context) -> Self::ComputedValue {
match *self {
TrackBreadth::Breadth(ref lop) => TrackBreadth::Breadth(lop.to_computed_value(context)),
TrackBreadth::Flex(fr) => TrackBreadth::Flex(fr),
TrackBreadth::Keyword(k) => TrackBreadth::Keyword(k),
}
}
#[inline]
fn from_computed_value(computed: &Self::ComputedValue) -> Self {
match *computed {
TrackBreadth::Breadth(ref lop) =>
TrackBreadth::Breadth(ToComputedValue::from_computed_value(lop)),
TrackBreadth::Flex(fr) => TrackBreadth::Flex(fr),
TrackBreadth::Keyword(k) => TrackBreadth::Keyword(k),
}
}
}
#[derive(Clone, Debug, HasViewportPercentage, PartialEq)]
#[cfg_attr(feature = "servo", derive(HeapSizeOf))]
/// A `<track-size>` type for explicit grid track sizing. Like `<track-breadth>`, this is
/// generic only to avoid code bloat. It only takes `<length-percentage>`
///
/// https://drafts.csswg.org/css-grid/#typedef-track-size
pub enum TrackSize<L> {
/// A flexible `<track-breadth>`
Breadth(TrackBreadth<L>),
/// A `minmax` function for a range over an inflexible `<track-breadth>`
/// and a flexible `<track-breadth>`
///
/// https://drafts.csswg.org/css-grid/#valdef-grid-template-columns-minmax
MinMax(TrackBreadth<L>, TrackBreadth<L>),
/// A `fit-content` function.
///
/// https://drafts.csswg.org/css-grid/#valdef-grid-template-columns-fit-content
FitContent(L),
}
impl<L> TrackSize<L> {
/// Check whether this is a `<fixed-size>`
///
/// https://drafts.csswg.org/css-grid/#typedef-fixed-size
pub fn is_fixed(&self) -> bool {
match *self {
TrackSize::Breadth(ref breadth) => breadth.is_fixed(),
// For minmax function, it could be either
// minmax(<fixed-breadth>, <track-breadth>) or minmax(<inflexible-breadth>, <fixed-breadth>),
// and since both variants are a subset of minmax(<inflexible-breadth>, <track-breadth>), we only
// need to make sure that they're fixed. So, we don't have to modify the parsing function.
TrackSize::MinMax(ref breadth_1, ref breadth_2) => {
if breadth_1.is_fixed() {
return true // the second value is always a <track-breadth>
}
match *breadth_1 {
TrackBreadth::Flex(_) => false, // should be <inflexible-breadth> at this point
_ => breadth_2.is_fixed(),
}
},
TrackSize::FitContent(_) => false,
}
}
}
impl<L> Default for TrackSize<L> {
fn default() -> Self {
TrackSize::Breadth(TrackBreadth::Keyword(TrackKeyword::Auto))
}
}
impl Parse for TrackSize<LengthOrPercentage> {
fn parse(context: &ParserContext, input: &mut Parser) -> Result<Self, ()> {
if let Ok(b) = input.try(|i| TrackBreadth::parse(context, i)) {
@ -301,59 +78,6 @@ impl Parse for TrackSize<LengthOrPercentage> {
}
}
impl<L: ToCss> ToCss for TrackSize<L> {
fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
match *self {
TrackSize::Breadth(ref b) => b.to_css(dest),
TrackSize::MinMax(ref infexible, ref flexible) => {
dest.write_str("minmax(")?;
infexible.to_css(dest)?;
dest.write_str(", ")?;
flexible.to_css(dest)?;
dest.write_str(")")
},
TrackSize::FitContent(ref lop) => {
dest.write_str("fit-content(")?;
lop.to_css(dest)?;
dest.write_str(")")
},
}
}
}
impl<L: ToComputedValue> ToComputedValue for TrackSize<L> {
type ComputedValue = TrackSize<L::ComputedValue>;
#[inline]
fn to_computed_value(&self, context: &Context) -> Self::ComputedValue {
match *self {
TrackSize::Breadth(ref b) => match *b {
// <flex> outside `minmax()` expands to `mimmax(auto, <flex>)`
// https://drafts.csswg.org/css-grid/#valdef-grid-template-columns-flex
TrackBreadth::Flex(f) =>
TrackSize::MinMax(TrackBreadth::Keyword(TrackKeyword::Auto), TrackBreadth::Flex(f)),
_ => TrackSize::Breadth(b.to_computed_value(context)),
},
TrackSize::MinMax(ref b_1, ref b_2) =>
TrackSize::MinMax(b_1.to_computed_value(context), b_2.to_computed_value(context)),
TrackSize::FitContent(ref lop) => TrackSize::FitContent(lop.to_computed_value(context)),
}
}
#[inline]
fn from_computed_value(computed: &Self::ComputedValue) -> Self {
match *computed {
TrackSize::Breadth(ref b) =>
TrackSize::Breadth(ToComputedValue::from_computed_value(b)),
TrackSize::MinMax(ref b_1, ref b_2) =>
TrackSize::MinMax(ToComputedValue::from_computed_value(b_1),
ToComputedValue::from_computed_value(b_2)),
TrackSize::FitContent(ref lop) =>
TrackSize::FitContent(ToComputedValue::from_computed_value(lop)),
}
}
}
/// Parse the grid line names into a vector of owned strings.
///
/// https://drafts.csswg.org/css-grid/#typedef-line-names
@ -373,69 +97,6 @@ pub fn parse_line_names(input: &mut Parser) -> Result<Vec<String>, ()> {
})
}
fn concat_serialize_idents<W>(prefix: &str, suffix: &str,
slice: &[String], sep: &str, dest: &mut W) -> fmt::Result
where W: fmt::Write
{
if let Some((ref first, rest)) = slice.split_first() {
dest.write_str(prefix)?;
serialize_identifier(first, dest)?;
for thing in rest {
dest.write_str(sep)?;
serialize_identifier(thing, dest)?;
}
dest.write_str(suffix)?;
}
Ok(())
}
/// The initial argument of the `repeat` function.
///
/// https://drafts.csswg.org/css-grid/#typedef-track-repeat
#[derive(Clone, Copy, PartialEq, Debug)]
#[cfg_attr(feature = "servo", derive(HeapSizeOf))]
pub enum RepeatCount {
/// A positive integer. This is allowed only for `<track-repeat>` and `<fixed-repeat>`
Number(Integer),
/// An `<auto-fill>` keyword allowed only for `<auto-repeat>`
AutoFill,
/// An `<auto-fit>` keyword allowed only for `<auto-repeat>`
AutoFit,
}
impl Parse for RepeatCount {
fn parse(context: &ParserContext, input: &mut Parser) -> Result<Self, ()> {
if let Ok(i) = input.try(|i| Integer::parse(context, i)) {
if i.value > 0 {
Ok(RepeatCount::Number(i))
} else {
Err(())
}
} else {
match_ignore_ascii_case! { &input.expect_ident()?,
"auto-fill" => Ok(RepeatCount::AutoFill),
"auto-fit" => Ok(RepeatCount::AutoFit),
_ => Err(()),
}
}
}
}
impl ToCss for RepeatCount {
fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
match *self {
RepeatCount::Number(ref c) => c.to_css(dest),
RepeatCount::AutoFill => dest.write_str("auto-fill"),
RepeatCount::AutoFit => dest.write_str("auto-fit"),
}
}
}
impl ComputedValueAsSpecified for RepeatCount {}
no_viewport_percentage!(RepeatCount);
/// The type of `repeat` function (only used in parsing).
///
/// https://drafts.csswg.org/css-grid/#typedef-track-repeat
@ -450,25 +111,6 @@ enum RepeatType {
Fixed,
}
/// The structure containing `<line-names>` and `<track-size>` values.
///
/// It can also hold `repeat()` function parameters, which expands into the respective
/// values in its computed form.
#[derive(Clone, PartialEq, Debug)]
#[cfg_attr(feature = "servo", derive(HeapSizeOf))]
pub struct TrackRepeat<L> {
/// The number of times for the value to be repeated (could also be `auto-fit` or `auto-fill`)
pub count: RepeatCount,
/// `<line-names>` accompanying `<track_size>` values.
///
/// If there's no `<line-names>`, then it's represented by an empty vector.
/// For N `<track-size>` values, there will be N+1 `<line-names>`, and so this vector's
/// length is always one value more than that of the `<track-size>`.
pub line_names: Vec<Vec<String>>,
/// `<track-size>` values.
pub track_sizes: Vec<TrackSize<L>>,
}
impl TrackRepeat<LengthOrPercentage> {
fn parse_with_repeat_type(context: &ParserContext, input: &mut Parser)
-> Result<(TrackRepeat<LengthOrPercentage>, RepeatType), ()> {
@ -525,32 +167,6 @@ impl TrackRepeat<LengthOrPercentage> {
}
}
impl<L: ToCss> ToCss for TrackRepeat<L> {
fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
dest.write_str("repeat(")?;
self.count.to_css(dest)?;
dest.write_str(", ")?;
let mut line_names_iter = self.line_names.iter();
for (i, (ref size, ref names)) in self.track_sizes.iter()
.zip(&mut line_names_iter).enumerate() {
if i > 0 {
dest.write_str(" ")?;
}
concat_serialize_idents("[", "] ", names, " ", dest)?;
size.to_css(dest)?;
}
if let Some(line_names_last) = line_names_iter.next() {
concat_serialize_idents(" [", "]", line_names_last, " ", dest)?;
}
dest.write_str(")")?;
Ok(())
}
}
impl HasViewportPercentage for TrackRepeat<LengthOrPercentage> {
#[inline]
fn has_viewport_percentage(&self) -> bool {
@ -558,112 +174,6 @@ impl HasViewportPercentage for TrackRepeat<LengthOrPercentage> {
}
}
impl<L: ToComputedValue> ToComputedValue for TrackRepeat<L> {
type ComputedValue = TrackRepeat<L::ComputedValue>;
#[inline]
fn to_computed_value(&self, context: &Context) -> Self::ComputedValue {
// If the repeat count is numeric, then expand the values and merge accordingly.
if let RepeatCount::Number(num) = self.count {
let mut line_names = vec![];
let mut track_sizes = vec![];
let mut prev_names = vec![];
for _ in 0..num.value {
let mut names_iter = self.line_names.iter();
for (size, names) in self.track_sizes.iter().zip(&mut names_iter) {
prev_names.extend_from_slice(&names);
line_names.push(mem::replace(&mut prev_names, vec![]));
track_sizes.push(size.to_computed_value(context));
}
if let Some(names) = names_iter.next() {
prev_names.extend_from_slice(&names);
}
}
line_names.push(prev_names);
TrackRepeat {
count: self.count,
track_sizes: track_sizes,
line_names: line_names,
}
} else { // if it's auto-fit/auto-fill, then it's left to the layout.
TrackRepeat {
count: self.count,
track_sizes: self.track_sizes.iter()
.map(|l| l.to_computed_value(context))
.collect(),
line_names: self.line_names.clone(),
}
}
}
#[inline]
fn from_computed_value(computed: &Self::ComputedValue) -> Self {
TrackRepeat {
count: computed.count,
track_sizes: computed.track_sizes.iter()
.map(ToComputedValue::from_computed_value)
.collect(),
line_names: computed.line_names.clone(),
}
}
}
/// The type of a `<track-list>` as determined during parsing.
///
/// https://drafts.csswg.org/css-grid/#typedef-track-list
#[derive(Clone, Copy, PartialEq, Debug)]
#[cfg_attr(feature = "servo", derive(HeapSizeOf))]
pub enum TrackListType {
/// [`<auto-track-list>`](https://drafts.csswg.org/css-grid/#typedef-auto-track-list)
///
/// If this type exists, then the value at the index in `line_names` field in `TrackList`
/// has the `<line-names>?` list that comes before `<auto-repeat>`. If it's a specified value,
/// then the `repeat()` function (that follows the line names list) is also at the given index
/// in `values` field. On the contrary, if it's a computed value, then the `repeat()` function
/// is in the `auto_repeat` field.
Auto(u16),
/// [`<track-list>`](https://drafts.csswg.org/css-grid/#typedef-track-list)
Normal,
/// [`<explicit-track-list>`](https://drafts.csswg.org/css-grid/#typedef-explicit-track-list)
///
/// Note that this is a subset of the normal `<track-list>`, and so it could be used in place
/// of the latter.
Explicit,
}
/// A grid `<track-list>` type.
///
/// https://drafts.csswg.org/css-grid/#typedef-track-list
#[derive(Clone, PartialEq, Debug)]
#[cfg_attr(feature = "servo", derive(HeapSizeOf))]
pub struct TrackList<T> {
/// The type of this `<track-list>` (auto, explicit or general).
///
/// In order to avoid parsing the same value multiple times, this does a single traversal
/// and arrives at the type of value it has parsed (or bails out gracefully with an error).
pub list_type: TrackListType,
/// A vector of `<track-size> | <track-repeat>` values. In its specified form, it may contain
/// any value, but once it's computed, it contains only `<track_size>` values.
///
/// Note that this may also contain `<auto-repeat>` at an index. If it exists, it's
/// given by the index in `TrackListType::Auto`
pub values: Vec<T>,
/// `<line-names>` accompanying `<track-size> | <track-repeat>` values.
///
/// If there's no `<line-names>`, then it's represented by an empty vector.
/// For N values, there will be N+1 `<line-names>`, and so this vector's
/// length is always one value more than that of the `<track-size>`.
pub line_names: Vec<Vec<String>>,
/// `<auto-repeat>` value after computation. This field is necessary, because
/// the `values` field (after computation) will only contain `<track-size>` values, and
/// we need something to represent this function.
pub auto_repeat: Option<TrackRepeat<computed::LengthOrPercentage>>,
}
/// Either a `<track-size>` or `<track-repeat>` component of `<track-list>`
///
/// This is required only for the specified form of `<track-list>`, and will become
@ -739,49 +249,6 @@ impl Parse for TrackList<TrackSizeOrRepeat> {
}
}
impl<T: ToCss> ToCss for TrackList<T> {
fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
let auto_idx = match self.list_type {
TrackListType::Auto(i) => i as usize,
_ => usize::MAX,
};
let mut values_iter = self.values.iter().peekable();
let mut line_names_iter = self.line_names.iter().peekable();
for idx in 0.. {
let names = line_names_iter.next().unwrap(); // This should exist!
concat_serialize_idents("[", "]", names, " ", dest)?;
match self.auto_repeat {
Some(ref repeat) if idx == auto_idx => {
if !names.is_empty() {
dest.write_str(" ")?;
}
repeat.to_css(dest)?;
},
_ => match values_iter.next() {
Some(value) => {
if !names.is_empty() {
dest.write_str(" ")?;
}
value.to_css(dest)?;
},
None => break,
},
}
if values_iter.peek().is_some() || line_names_iter.peek().map_or(false, |v| !v.is_empty()) {
dest.write_str(" ")?;
}
}
Ok(())
}
}
impl HasViewportPercentage for TrackList<TrackSizeOrRepeat> {
#[inline]
fn has_viewport_percentage(&self) -> bool {