Source code
Revision control
Copy as Markdown
Other Tools
/* 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
//! A style rule.
use crate::properties::PropertyDeclarationBlock;
use crate::selector_parser::SelectorImpl;
use crate::shared_lock::{
DeepCloneParams, DeepCloneWithLock, Locked, SharedRwLock, SharedRwLockReadGuard, ToCssWithGuard,
};
use crate::str::CssStringWriter;
use crate::stylesheets::CssRules;
use cssparser::SourceLocation;
#[cfg(feature = "gecko")]
use malloc_size_of::{
MallocSizeOf, MallocSizeOfOps, MallocUnconditionalShallowSizeOf, MallocUnconditionalSizeOf,
};
use selectors::SelectorList;
use servo_arc::Arc;
use std::fmt::{self, Write};
/// A style rule, with selectors and declarations.
#[derive(Debug, ToShmem)]
pub struct StyleRule {
/// The list of selectors in this rule.
pub selectors: SelectorList<SelectorImpl>,
/// The declaration block with the properties it contains.
pub block: Arc<Locked<PropertyDeclarationBlock>>,
/// The nested rules to this style rule. Only non-`None` when nesting is enabled.
pub rules: Option<Arc<Locked<CssRules>>>,
/// The location in the sheet where it was found.
pub source_location: SourceLocation,
}
impl DeepCloneWithLock for StyleRule {
/// Deep clones this StyleRule.
fn deep_clone_with_lock(
&self,
lock: &SharedRwLock,
guard: &SharedRwLockReadGuard,
params: &DeepCloneParams,
) -> StyleRule {
StyleRule {
selectors: self.selectors.clone(),
block: Arc::new(lock.wrap(self.block.read_with(guard).clone())),
rules: self.rules.as_ref().map(|rules| {
let rules = rules.read_with(guard);
Arc::new(lock.wrap(rules.deep_clone_with_lock(lock, guard, params)))
}),
source_location: self.source_location.clone(),
}
}
}
impl StyleRule {
/// Measure heap usage.
#[cfg(feature = "gecko")]
pub fn size_of(&self, guard: &SharedRwLockReadGuard, ops: &mut MallocSizeOfOps) -> usize {
let mut n = 0;
n += self.selectors.unconditional_size_of(ops);
n += self.block.unconditional_shallow_size_of(ops) +
self.block.read_with(guard).size_of(ops);
if let Some(ref rules) = self.rules {
n += rules.unconditional_shallow_size_of(ops) +
rules.read_with(guard).size_of(guard, ops)
}
n
}
}
impl ToCssWithGuard for StyleRule {
fn to_css(&self, guard: &SharedRwLockReadGuard, dest: &mut CssStringWriter) -> fmt::Result {
use cssparser::ToCss;
// Step 1
self.selectors.to_css(dest)?;
dest.write_str(" {")?;
// Step 2
let declaration_block = self.block.read_with(guard);
let has_declarations = !declaration_block.declarations().is_empty();
// Step 3
if let Some(ref rules) = self.rules {
let rules = rules.read_with(guard);
// Step 6 (here because it's more convenient)
if !rules.is_empty() {
if has_declarations {
dest.write_str("\n ")?;
declaration_block.to_css(dest)?;
}
return rules.to_css_block_without_opening(guard, dest);
}
}
// Steps 4 & 5
if has_declarations {
dest.write_char(' ')?;
declaration_block.to_css(dest)?;
}
dest.write_str(" }")
}
}