mirror of
https://github.com/servo/servo.git
synced 2025-08-06 14:10:11 +01:00
style: Make 'grid-area'/'grid-column'/'grid-row' shorthands serialize to shortest possible form.
Differential Revision: https://phabricator.services.mozilla.com/D54386
This commit is contained in:
parent
70ec6ffe36
commit
4359b3bd47
2 changed files with 55 additions and 4 deletions
|
@ -181,8 +181,18 @@
|
|||
}
|
||||
|
||||
impl<'a> ToCss for LonghandsToSerialize<'a> {
|
||||
// Return the shortest possible serialization of the `grid-${kind}-[start/end]` values.
|
||||
// This function exploits the opportunities to omit the end value per this spec text:
|
||||
//
|
||||
// https://drafts.csswg.org/css-grid/#propdef-grid-column
|
||||
// "When the second value is omitted, if the first value is a <custom-ident>,
|
||||
// the grid-row-end/grid-column-end longhand is also set to that <custom-ident>;
|
||||
// otherwise, it is set to auto."
|
||||
fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result where W: fmt::Write {
|
||||
self.grid_${kind}_start.to_css(dest)?;
|
||||
if self.grid_${kind}_start.can_omit(self.grid_${kind}_end) {
|
||||
return Ok(()); // the end value is redundant
|
||||
}
|
||||
dest.write_str(" / ")?;
|
||||
self.grid_${kind}_end.to_css(dest)
|
||||
}
|
||||
|
@ -247,14 +257,39 @@
|
|||
}
|
||||
|
||||
impl<'a> ToCss for LonghandsToSerialize<'a> {
|
||||
// Return the shortest possible serialization of the `grid-[column/row]-[start/end]` values.
|
||||
// This function exploits the opportunities to omit trailing values per this spec text:
|
||||
//
|
||||
// https://drafts.csswg.org/css-grid/#propdef-grid-area
|
||||
// "If four <grid-line> values are specified, grid-row-start is set to the first value,
|
||||
// grid-column-start is set to the second value, grid-row-end is set to the third value,
|
||||
// and grid-column-end is set to the fourth value.
|
||||
//
|
||||
// When grid-column-end is omitted, if grid-column-start is a <custom-ident>,
|
||||
// grid-column-end is set to that <custom-ident>; otherwise, it is set to auto.
|
||||
//
|
||||
// When grid-row-end is omitted, if grid-row-start is a <custom-ident>, grid-row-end is
|
||||
// set to that <custom-ident>; otherwise, it is set to auto.
|
||||
//
|
||||
// When grid-column-start is omitted, if grid-row-start is a <custom-ident>, all four
|
||||
// longhands are set to that value. Otherwise, it is set to auto."
|
||||
fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result where W: fmt::Write {
|
||||
self.grid_row_start.to_css(dest)?;
|
||||
let mut trailing_values = 3;
|
||||
if self.grid_column_start.can_omit(self.grid_column_end) {
|
||||
trailing_values -= 1;
|
||||
if self.grid_row_start.can_omit(self.grid_row_end) {
|
||||
trailing_values -= 1;
|
||||
if self.grid_row_start.can_omit(self.grid_column_start) {
|
||||
trailing_values -= 1;
|
||||
}
|
||||
}
|
||||
}
|
||||
let values = [&self.grid_column_start, &self.grid_row_end, &self.grid_column_end];
|
||||
for value in &values {
|
||||
for value in values.iter().take(trailing_values) {
|
||||
dest.write_str(" / ")?;
|
||||
value.to_css(dest)?;
|
||||
}
|
||||
|
||||
Ok(())
|
||||
}
|
||||
}
|
||||
|
|
|
@ -58,7 +58,7 @@ pub use self::GenericGridLine as GridLine;
|
|||
|
||||
impl<Integer> GridLine<Integer>
|
||||
where
|
||||
Integer: Zero,
|
||||
Integer: PartialEq + Zero,
|
||||
{
|
||||
/// The `auto` value.
|
||||
pub fn auto() -> Self {
|
||||
|
@ -73,11 +73,27 @@ where
|
|||
pub fn is_auto(&self) -> bool {
|
||||
self.ident == atom!("") && self.line_num.is_zero() && !self.is_span
|
||||
}
|
||||
|
||||
/// Check whether this `<grid-line>` represents a `<custom-ident>` value.
|
||||
pub fn is_ident_only(&self) -> bool {
|
||||
self.ident != atom!("") && self.line_num.is_zero() && !self.is_span
|
||||
}
|
||||
|
||||
/// Check if `self` makes `other` omittable according to the rules at:
|
||||
/// https://drafts.csswg.org/css-grid/#propdef-grid-column
|
||||
/// https://drafts.csswg.org/css-grid/#propdef-grid-area
|
||||
pub fn can_omit(&self, other: &Self) -> bool {
|
||||
if self.is_ident_only() {
|
||||
self == other
|
||||
} else {
|
||||
other.is_auto()
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<Integer> ToCss for GridLine<Integer>
|
||||
where
|
||||
Integer: ToCss + Zero,
|
||||
Integer: ToCss + PartialEq + Zero,
|
||||
{
|
||||
fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
|
||||
where
|
||||
|
|
Loading…
Add table
Add a link
Reference in a new issue