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SimonSapinSimonSapin
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Add an incomplete CSS serializer.
Serialization is considered correct if it maintains the invariant: parse(serialize(parse(text))) == parse(text) for any text (Unicode string.) This is not the case of this code yet (see servo#24), but it’s good enough for error reporting in Servo.
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‎Makefile.in

+1-1
Original file line numberDiff line numberDiff line change
@@ -22,7 +22,7 @@ cssparser-test: lib.rs $(RUST_SRC)
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.PHONY: check
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check: cssparser-test
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./cssparser-test
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./cssparser-test $(TEST)
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.PHONY: check-debug
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check-debug: cssparser-tests

‎lib.rs

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Original file line numberDiff line numberDiff line change
@@ -13,12 +13,14 @@ pub use tokenizer::*;
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pub use parser::*;
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pub use color::*;
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pub use nth::*;
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pub use serializer::{ToCss, serialize_identifier, serialize_string};
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pub mod ast;
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pub mod tokenizer;
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pub mod parser;
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pub mod color;
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pub mod nth;
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pub mod serializer;
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#[cfg(test)]
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mod tests;

‎serializer.rs

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,212 @@
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/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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use ast;
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use ast::*;
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impl ast::ComponentValue {
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pub fn to_css(&mut self) -> ~str {
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let mut css = ~"";
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self.to_css_push(&mut css);
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css
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}
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pub fn to_css_push(&self, css: &mut ~str) {
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match *self {
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Ident(ref value) => serialize_identifier(value.as_slice(), css),
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AtKeyword(ref value) => {
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css.push_char('@');
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serialize_identifier(value.as_slice(), css);
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},
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Hash(ref value) | IDHash(ref value) => {
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css.push_char('#');
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serialize_identifier(value.as_slice(), css);
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}
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String(ref value) => serialize_string(value.as_slice(), css),
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URL(ref value) => {
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css.push_str("url(");
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serialize_string(value.as_slice(), css);
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css.push_char(')');
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},
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Delim(value) => css.push_char(value),
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Number(ref value) => css.push_str(value.representation),
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Percentage(ref value) => {
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css.push_str(value.representation);
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css.push_char('%');
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},
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Dimension(ref value, ref unit) => {
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css.push_str(value.representation);
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serialize_identifier(unit.as_slice(), css);
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},
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UnicodeRange(start, end) => {
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css.push_str(format!("U+{:X}", start));
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if end != start {
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css.push_str(format!("-{:X}", end));
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}
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}
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WhiteSpace => css.push_char(' '),
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Colon => css.push_char(':'),
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Semicolon => css.push_char(';'),
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Comma => css.push_char(','),
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IncludeMatch => css.push_str("~="),
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DashMatch => css.push_str("|="),
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PrefixMatch => css.push_str("^="),
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SuffixMatch => css.push_str("$="),
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SubstringMatch => css.push_str("*="),
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Column => css.push_str("||"),
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CDO => css.push_str("<!--"),
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CDC => css.push_str("-->"),
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Function(ref name, ref arguments) => {
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serialize_identifier(name.as_slice(), css);
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css.push_char('(');
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arguments.iter().to_css_push(css);
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css.push_char(')');
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},
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ParenthesisBlock(ref content) => {
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css.push_char('(');
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content.iter().to_css_push(css);
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css.push_char(')');
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},
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SquareBracketBlock(ref content) => {
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css.push_char('[');
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content.iter().to_css_push(css);
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css.push_char(']');
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},
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CurlyBracketBlock(ref content) => {
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css.push_char('{');
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content.iter().map(|t| match *t { (ref c, _) => c }).to_css_push(css);
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css.push_char('}');
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},
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BadURL => css.push_str("url(<bad url>)"),
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BadString => css.push_str("\"<bad string>\n"),
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CloseParenthesis => css.push_char(')'),
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CloseSquareBracket => css.push_char(']'),
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CloseCurlyBracket => css.push_char('}'),
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}
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}
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}
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pub fn serialize_identifier(value: &str, css: &mut ~str) {
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// TODO: avoid decoding/re-encoding UTF-8?
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let mut iter = value.iter();
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let mut c = iter.next().unwrap();
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if c == '-' {
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c = match iter.next() {
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None => {
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css.push_str("\\-");
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return
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}
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Some(c) => {
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css.push_char('-');
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c
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},
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}
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};
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match c {
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'A'..'Z' | 'a'..'z' | '_' => css.push_char(c),
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_ if c > '\x7F' => css.push_char(c),
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'\n' => css.push_str("\\A "),
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'\r' => css.push_str("\\D "),
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'\x0C' => css.push_str("\\C "),
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'0'..'9' => css.push_str(format!("\\\\3{} ", c)),
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_ => { css.push_char('\\'); css.push_char(c) },
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}
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for c in iter {
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match c {
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'0'..'9' | 'A'..'Z' | 'a'..'z' | '_' | '-' => css.push_char(c),
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_ if c > '\x7F' => css.push_char(c),
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'\n' => css.push_str("\\A "),
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'\r' => css.push_str("\\D "),
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'\x0C' => css.push_str("\\C "),
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_ => { css.push_char('\\'); css.push_char(c) },
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}
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}
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}
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pub fn serialize_string(value: &str, css: &mut ~str) {
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css.push_char('"');
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// TODO: avoid decoding/re-encoding UTF-8?
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for c in value.iter() {
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match c {
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'"' => css.push_str("\""),
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'\\' => css.push_str("\\\\"),
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'\n' => css.push_str("\\A "),
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'\r' => css.push_str("\\D "),
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'\x0C' => css.push_str("\\C "),
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_ => css.push_char(c),
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}
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}
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css.push_char('"');
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}
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pub trait ToCss {
152+
fn to_css(&mut self) -> ~str {
153+
let mut css = ~"";
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self.to_css_push(&mut css);
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css
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}
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fn to_css_push(&mut self, css: &mut ~str);
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}
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impl<'self, I: Iterator<&'self ComponentValue>> ToCss for I {
163+
fn to_css_push(&mut self, css: &mut ~str) {
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let mut previous = match self.next() {
165+
None => return,
166+
Some(first) => { first.to_css_push(css); first }
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};
168+
macro_rules! matches(
169+
($value:expr, $($pattern:pat)|+) => (
170+
match $value { $($pattern)|+ => true, _ => false }
171+
);
172+
)
173+
loop { match self.next() { None => break, Some(component_value) => {
174+
let (a, b) = (previous, component_value);
175+
if (
176+
matches!(*a, Hash(*) | IDHash(*) | AtKeyword(*)) &&
177+
matches!(*b, Number(*) | Percentage(*) | Ident(*) | Dimension(*) |
178+
UnicodeRange(*) | URL(*) | Function(*))
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) || (
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matches!(*a, Number(*) | Ident(*) | Dimension(*)) &&
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matches!(*b, Number(*) | Ident(*) | Dimension(*))
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) || (
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matches!(*a, Number(*) | Ident(*) | Dimension(*)) &&
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matches!(*b, Percentage(*) | UnicodeRange(*) | URL(*) | Function(*))
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) || (
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matches!(*a, Ident(*)) &&
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matches!(*b, ParenthesisBlock(*))
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) || (
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matches!(*a, Delim('#') | Delim('@')) &&
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!matches!(*b, WhiteSpace)
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) || (
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matches!(*a, Delim('-') | Delim('+') | Delim('.') | Delim('<') |
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Delim('>') | Delim('!')) &&
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!matches!(*b, WhiteSpace)
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) || (
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!matches!(*a, WhiteSpace) &&
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matches!(*b, Delim('-') | Delim('+') | Delim('.') | Delim('<') |
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Delim('>') | Delim('!'))
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) || (
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matches!(*a, Delim('/')) &&
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matches!(*b, Delim('*'))
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) || (
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matches!(*a, Delim('*')) &&
204+
matches!(*b, Delim('/'))
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) {
206+
css.push_str("/**/")
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}
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component_value.to_css_push(css);
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previous = component_value;
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}}}
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}
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}

‎tests.rs

+12
Original file line numberDiff line numberDiff line change
@@ -173,6 +173,18 @@ fn nth() {
173173
}
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// FIXME: serializer tests disabled for now
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// https://github.com/mozilla-servo/rust-cssparser/issues/24
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//#[test]
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fn serializer() {
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do run_json_tests(include_str!("css-parsing-tests/component_value_list.json")) |input| {
181+
let component_values = tokenize(input).map(|(c, _)| c).to_owned_vec();
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let serialized = component_values.iter().to_css();
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tokenize(serialized).map(|(c, _)| c).to_owned_vec()
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}
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}
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impl ToJson for Result<Rule, SyntaxError> {
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fn to_json(&self) -> json::Json {
178190
match *self {

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