Adding upstream version 115.8.0esr.upstream/115.8.0esr

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 599 insertions, 0 deletions

diff --git a/servo/components/style/attr.rs b/servo/components/style/attr.rs
new file mode 100644
index 0000000000..05833fa08d
--- /dev/null
+++ b/servo/components/style/attr.rs
@@ -0,0 +1,599 @@
+/* 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
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+//! Parsed representations of [DOM attributes][attr].
+//!
+//! [attr]: https://dom.spec.whatwg.org/#interface-attr
+
+use crate::properties::PropertyDeclarationBlock;
+use crate::shared_lock::Locked;
+use crate::str::str_join;
+use crate::str::{read_exponent, read_fraction, HTML_SPACE_CHARACTERS};
+use crate::str::{read_numbers, split_commas, split_html_space_chars};
+use crate::values::specified::Length;
+use crate::values::AtomString;
+use crate::{Atom, LocalName, Namespace, Prefix};
+use app_units::Au;
+use cssparser::{self, Color, RGBA};
+use euclid::num::Zero;
+use num_traits::ToPrimitive;
+use selectors::attr::AttrSelectorOperation;
+use servo_arc::Arc;
+use servo_url::ServoUrl;
+use std::str::FromStr;
+
+// Duplicated from script::dom::values.
+const UNSIGNED_LONG_MAX: u32 = 2147483647;
+
+#[derive(Clone, Copy, Debug, PartialEq)]
+#[cfg_attr(feature = "servo", derive(MallocSizeOf))]
+pub enum LengthOrPercentageOrAuto {
+    Auto,
+    Percentage(f32),
+    Length(Au),
+}
+
+#[derive(Clone, Debug)]
+#[cfg_attr(feature = "servo", derive(MallocSizeOf))]
+pub enum AttrValue {
+    String(String),
+    TokenList(String, Vec<Atom>),
+    UInt(String, u32),
+    Int(String, i32),
+    Double(String, f64),
+    Atom(Atom),
+    Length(String, Option<Length>),
+    Color(String, Option<RGBA>),
+    Dimension(String, LengthOrPercentageOrAuto),
+
+    /// Stores a URL, computed from the input string and a document's base URL.
+    ///
+    /// The URL is resolved at setting-time, so this kind of attribute value is
+    /// not actually suitable for most URL-reflecting IDL attributes.
+    ResolvedUrl(String, Option<ServoUrl>),
+
+    /// Note that this variant is only used transitively as a fast path to set
+    /// the property declaration block relevant to the style of an element when
+    /// set from the inline declaration of that element (that is,
+    /// `element.style`).
+    ///
+    /// This can, as of this writing, only correspond to the value of the
+    /// `style` element, and is set from its relevant CSSInlineStyleDeclaration,
+    /// and then converted to a string in Element::attribute_mutated.
+    ///
+    /// Note that we don't necessarily need to do that (we could just clone the
+    /// declaration block), but that avoids keeping a refcounted
+    /// declarationblock for longer than needed.
+    Declaration(
+        String,
+        #[ignore_malloc_size_of = "Arc"] Arc<Locked<PropertyDeclarationBlock>>,
+    ),
+}
+
+/// Shared implementation to parse an integer according to
+/// <https://html.spec.whatwg.org/multipage/#rules-for-parsing-integers> or
+/// <https://html.spec.whatwg.org/multipage/#rules-for-parsing-non-negative-integers>
+fn do_parse_integer<T: Iterator<Item = char>>(input: T) -> Result<i64, ()> {
+    let mut input = input
+        .skip_while(|c| HTML_SPACE_CHARACTERS.iter().any(|s| s == c))
+        .peekable();
+
+    let sign = match input.peek() {
+        None => return Err(()),
+        Some(&'-') => {
+            input.next();
+            -1
+        },
+        Some(&'+') => {
+            input.next();
+            1
+        },
+        Some(_) => 1,
+    };
+
+    let (value, _) = read_numbers(input);
+
+    value.and_then(|value| value.checked_mul(sign)).ok_or(())
+}
+
+/// Parse an integer according to
+/// <https://html.spec.whatwg.org/multipage/#rules-for-parsing-integers>.
+pub fn parse_integer<T: Iterator<Item = char>>(input: T) -> Result<i32, ()> {
+    do_parse_integer(input).and_then(|result| result.to_i32().ok_or(()))
+}
+
+/// Parse an integer according to
+/// <https://html.spec.whatwg.org/multipage/#rules-for-parsing-non-negative-integers>
+pub fn parse_unsigned_integer<T: Iterator<Item = char>>(input: T) -> Result<u32, ()> {
+    do_parse_integer(input).and_then(|result| result.to_u32().ok_or(()))
+}
+
+/// Parse a floating-point number according to
+/// <https://html.spec.whatwg.org/multipage/#rules-for-parsing-floating-point-number-values>
+pub fn parse_double(string: &str) -> Result<f64, ()> {
+    let trimmed = string.trim_matches(HTML_SPACE_CHARACTERS);
+    let mut input = trimmed.chars().peekable();
+
+    let (value, divisor, chars_skipped) = match input.peek() {
+        None => return Err(()),
+        Some(&'-') => {
+            input.next();
+            (-1f64, -1f64, 1)
+        },
+        Some(&'+') => {
+            input.next();
+            (1f64, 1f64, 1)
+        },
+        _ => (1f64, 1f64, 0),
+    };
+
+    let (value, value_digits) = if let Some(&'.') = input.peek() {
+        (0f64, 0)
+    } else {
+        let (read_val, read_digits) = read_numbers(input);
+        (
+            value * read_val.and_then(|result| result.to_f64()).unwrap_or(1f64),
+            read_digits,
+        )
+    };
+
+    let input = trimmed
+        .chars()
+        .skip(value_digits + chars_skipped)
+        .peekable();
+
+    let (mut value, fraction_digits) = read_fraction(input, divisor, value);
+
+    let input = trimmed
+        .chars()
+        .skip(value_digits + chars_skipped + fraction_digits)
+        .peekable();
+
+    if let Some(exp) = read_exponent(input) {
+        value *= 10f64.powi(exp)
+    };
+
+    Ok(value)
+}
+
+impl AttrValue {
+    pub fn from_serialized_tokenlist(tokens: String) -> AttrValue {
+        let atoms =
+            split_html_space_chars(&tokens)
+                .map(Atom::from)
+                .fold(vec![], |mut acc, atom| {
+                    if !acc.contains(&atom) {
+                        acc.push(atom)
+                    }
+                    acc
+                });
+        AttrValue::TokenList(tokens, atoms)
+    }
+
+    pub fn from_comma_separated_tokenlist(tokens: String) -> AttrValue {
+        let atoms = split_commas(&tokens)
+            .map(Atom::from)
+            .fold(vec![], |mut acc, atom| {
+                if !acc.contains(&atom) {
+                    acc.push(atom)
+                }
+                acc
+            });
+        AttrValue::TokenList(tokens, atoms)
+    }
+
+    pub fn from_atomic_tokens(atoms: Vec<Atom>) -> AttrValue {
+        // TODO(ajeffrey): effecient conversion of Vec<Atom> to String
+        let tokens = String::from(str_join(&atoms, "\x20"));
+        AttrValue::TokenList(tokens, atoms)
+    }
+
+    // https://html.spec.whatwg.org/multipage/#reflecting-content-attributes-in-idl-attributes:idl-unsigned-long
+    pub fn from_u32(string: String, default: u32) -> AttrValue {
+        let result = parse_unsigned_integer(string.chars()).unwrap_or(default);
+        let result = if result > UNSIGNED_LONG_MAX {
+            default
+        } else {
+            result
+        };
+        AttrValue::UInt(string, result)
+    }
+
+    pub fn from_i32(string: String, default: i32) -> AttrValue {
+        let result = parse_integer(string.chars()).unwrap_or(default);
+        AttrValue::Int(string, result)
+    }
+
+    // https://html.spec.whatwg.org/multipage/#reflecting-content-attributes-in-idl-attributes:idl-double
+    pub fn from_double(string: String, default: f64) -> AttrValue {
+        let result = parse_double(&string).unwrap_or(default);
+
+        if result.is_normal() {
+            AttrValue::Double(string, result)
+        } else {
+            AttrValue::Double(string, default)
+        }
+    }
+
+    // https://html.spec.whatwg.org/multipage/#limited-to-only-non-negative-numbers
+    pub fn from_limited_i32(string: String, default: i32) -> AttrValue {
+        let result = parse_integer(string.chars()).unwrap_or(default);
+
+        if result < 0 {
+            AttrValue::Int(string, default)
+        } else {
+            AttrValue::Int(string, result)
+        }
+    }
+
+    // https://html.spec.whatwg.org/multipage/#limited-to-only-non-negative-numbers-greater-than-zero
+    pub fn from_limited_u32(string: String, default: u32) -> AttrValue {
+        let result = parse_unsigned_integer(string.chars()).unwrap_or(default);
+        let result = if result == 0 || result > UNSIGNED_LONG_MAX {
+            default
+        } else {
+            result
+        };
+        AttrValue::UInt(string, result)
+    }
+
+    pub fn from_atomic(string: String) -> AttrValue {
+        let value = Atom::from(string);
+        AttrValue::Atom(value)
+    }
+
+    pub fn from_resolved_url(base: &ServoUrl, url: String) -> AttrValue {
+        let joined = base.join(&url).ok();
+        AttrValue::ResolvedUrl(url, joined)
+    }
+
+    pub fn from_legacy_color(string: String) -> AttrValue {
+        let parsed = parse_legacy_color(&string).ok();
+        AttrValue::Color(string, parsed)
+    }
+
+    pub fn from_dimension(string: String) -> AttrValue {
+        let parsed = parse_length(&string);
+        AttrValue::Dimension(string, parsed)
+    }
+
+    pub fn from_nonzero_dimension(string: String) -> AttrValue {
+        let parsed = parse_nonzero_length(&string);
+        AttrValue::Dimension(string, parsed)
+    }
+
+    /// Assumes the `AttrValue` is a `TokenList` and returns its tokens
+    ///
+    /// ## Panics
+    ///
+    /// Panics if the `AttrValue` is not a `TokenList`
+    pub fn as_tokens(&self) -> &[Atom] {
+        match *self {
+            AttrValue::TokenList(_, ref tokens) => tokens,
+            _ => panic!("Tokens not found"),
+        }
+    }
+
+    /// Assumes the `AttrValue` is an `Atom` and returns its value
+    ///
+    /// ## Panics
+    ///
+    /// Panics if the `AttrValue` is not an `Atom`
+    pub fn as_atom(&self) -> &Atom {
+        match *self {
+            AttrValue::Atom(ref value) => value,
+            _ => panic!("Atom not found"),
+        }
+    }
+
+    /// Assumes the `AttrValue` is a `Color` and returns its value
+    ///
+    /// ## Panics
+    ///
+    /// Panics if the `AttrValue` is not a `Color`
+    pub fn as_color(&self) -> Option<&RGBA> {
+        match *self {
+            AttrValue::Color(_, ref color) => color.as_ref(),
+            _ => panic!("Color not found"),
+        }
+    }
+
+    /// Assumes the `AttrValue` is a `Dimension` and returns its value
+    ///
+    /// ## Panics
+    ///
+    /// Panics if the `AttrValue` is not a `Dimension`
+    pub fn as_dimension(&self) -> &LengthOrPercentageOrAuto {
+        match *self {
+            AttrValue::Dimension(_, ref l) => l,
+            _ => panic!("Dimension not found"),
+        }
+    }
+
+    /// Assumes the `AttrValue` is a `ResolvedUrl` and returns its value.
+    ///
+    /// ## Panics
+    ///
+    /// Panics if the `AttrValue` is not a `ResolvedUrl`
+    pub fn as_resolved_url(&self) -> Option<&ServoUrl> {
+        match *self {
+            AttrValue::ResolvedUrl(_, ref url) => url.as_ref(),
+            _ => panic!("Url not found"),
+        }
+    }
+
+    /// Return the AttrValue as its integer representation, if any.
+    /// This corresponds to attribute values returned as `AttrValue::UInt(_)`
+    /// by `VirtualMethods::parse_plain_attribute()`.
+    ///
+    /// ## Panics
+    ///
+    /// Panics if the `AttrValue` is not a `UInt`
+    pub fn as_uint(&self) -> u32 {
+        if let AttrValue::UInt(_, value) = *self {
+            value
+        } else {
+            panic!("Uint not found");
+        }
+    }
+
+    /// Return the AttrValue as a dimension computed from its integer
+    /// representation, assuming that integer representation specifies pixels.
+    ///
+    /// This corresponds to attribute values returned as `AttrValue::UInt(_)`
+    /// by `VirtualMethods::parse_plain_attribute()`.
+    ///
+    /// ## Panics
+    ///
+    /// Panics if the `AttrValue` is not a `UInt`
+    pub fn as_uint_px_dimension(&self) -> LengthOrPercentageOrAuto {
+        if let AttrValue::UInt(_, value) = *self {
+            LengthOrPercentageOrAuto::Length(Au::from_px(value as i32))
+        } else {
+            panic!("Uint not found");
+        }
+    }
+
+    pub fn eval_selector(&self, selector: &AttrSelectorOperation<&AtomString>) -> bool {
+        // FIXME(SimonSapin) this can be more efficient by matching on `(self, selector)` variants
+        // and doing Atom comparisons instead of string comparisons where possible,
+        // with SelectorImpl::AttrValue changed to Atom.
+        selector.eval_str(self)
+    }
+}
+
+impl ::std::ops::Deref for AttrValue {
+    type Target = str;
+
+    fn deref(&self) -> &str {
+        match *self {
+            AttrValue::String(ref value) |
+            AttrValue::TokenList(ref value, _) |
+            AttrValue::UInt(ref value, _) |
+            AttrValue::Double(ref value, _) |
+            AttrValue::Length(ref value, _) |
+            AttrValue::Color(ref value, _) |
+            AttrValue::Int(ref value, _) |
+            AttrValue::ResolvedUrl(ref value, _) |
+            AttrValue::Declaration(ref value, _) |
+            AttrValue::Dimension(ref value, _) => &value,
+            AttrValue::Atom(ref value) => &value,
+        }
+    }
+}
+
+impl PartialEq<Atom> for AttrValue {
+    fn eq(&self, other: &Atom) -> bool {
+        match *self {
+            AttrValue::Atom(ref value) => value == other,
+            _ => other == &**self,
+        }
+    }
+}
+
+/// <https://html.spec.whatwg.org/multipage/#rules-for-parsing-non-zero-dimension-values>
+pub fn parse_nonzero_length(value: &str) -> LengthOrPercentageOrAuto {
+    match parse_length(value) {
+        LengthOrPercentageOrAuto::Length(x) if x == Au::zero() => LengthOrPercentageOrAuto::Auto,
+        LengthOrPercentageOrAuto::Percentage(x) if x == 0. => LengthOrPercentageOrAuto::Auto,
+        x => x,
+    }
+}
+
+/// Parses a [legacy color][color]. If unparseable, `Err` is returned.
+///
+/// [color]: https://html.spec.whatwg.org/multipage/#rules-for-parsing-a-legacy-colour-value
+pub fn parse_legacy_color(mut input: &str) -> Result<RGBA, ()> {
+    // Steps 1 and 2.
+    if input.is_empty() {
+        return Err(());
+    }
+
+    // Step 3.
+    input = input.trim_matches(HTML_SPACE_CHARACTERS);
+
+    // Step 4.
+    if input.eq_ignore_ascii_case("transparent") {
+        return Err(());
+    }
+
+    // Step 5.
+    if let Ok(Color::RGBA(rgba)) = cssparser::parse_color_keyword(input) {
+        return Ok(rgba);
+    }
+
+    // Step 6.
+    if input.len() == 4 {
+        if let (b'#', Ok(r), Ok(g), Ok(b)) = (
+            input.as_bytes()[0],
+            hex(input.as_bytes()[1] as char),
+            hex(input.as_bytes()[2] as char),
+            hex(input.as_bytes()[3] as char),
+        ) {
+            return Ok(RGBA::new(r * 17, g * 17, b * 17, 255));
+        }
+    }
+
+    // Step 7.
+    let mut new_input = String::new();
+    for ch in input.chars() {
+        if ch as u32 > 0xffff {
+            new_input.push_str("00")
+        } else {
+            new_input.push(ch)
+        }
+    }
+    let mut input = &*new_input;
+
+    // Step 8.
+    for (char_count, (index, _)) in input.char_indices().enumerate() {
+        if char_count == 128 {
+            input = &input[..index];
+            break;
+        }
+    }
+
+    // Step 9.
+    if input.as_bytes()[0] == b'#' {
+        input = &input[1..]
+    }
+
+    // Step 10.
+    let mut new_input = Vec::new();
+    for ch in input.chars() {
+        if hex(ch).is_ok() {
+            new_input.push(ch as u8)
+        } else {
+            new_input.push(b'0')
+        }
+    }
+    let mut input = new_input;
+
+    // Step 11.
+    while input.is_empty() || (input.len() % 3) != 0 {
+        input.push(b'0')
+    }
+
+    // Step 12.
+    let mut length = input.len() / 3;
+    let (mut red, mut green, mut blue) = (
+        &input[..length],
+        &input[length..length * 2],
+        &input[length * 2..],
+    );
+
+    // Step 13.
+    if length > 8 {
+        red = &red[length - 8..];
+        green = &green[length - 8..];
+        blue = &blue[length - 8..];
+        length = 8
+    }
+
+    // Step 14.
+    while length > 2 && red[0] == b'0' && green[0] == b'0' && blue[0] == b'0' {
+        red = &red[1..];
+        green = &green[1..];
+        blue = &blue[1..];
+        length -= 1
+    }
+
+    // Steps 15-20.
+    return Ok(RGBA::new(
+        hex_string(red).unwrap(),
+        hex_string(green).unwrap(),
+        hex_string(blue).unwrap(),
+        255,
+    ));
+
+    fn hex(ch: char) -> Result<u8, ()> {
+        match ch {
+            '0'..='9' => Ok((ch as u8) - b'0'),
+            'a'..='f' => Ok((ch as u8) - b'a' + 10),
+            'A'..='F' => Ok((ch as u8) - b'A' + 10),
+            _ => Err(()),
+        }
+    }
+
+    fn hex_string(string: &[u8]) -> Result<u8, ()> {
+        match string.len() {
+            0 => Err(()),
+            1 => hex(string[0] as char),
+            _ => {
+                let upper = hex(string[0] as char)?;
+                let lower = hex(string[1] as char)?;
+                Ok((upper << 4) | lower)
+            },
+        }
+    }
+}
+
+/// Parses a [dimension value][dim]. If unparseable, `Auto` is returned.
+///
+/// [dim]: https://html.spec.whatwg.org/multipage/#rules-for-parsing-dimension-values
+// TODO: this function can be rewritten to return Result<LengthPercentage, _>
+pub fn parse_length(mut value: &str) -> LengthOrPercentageOrAuto {
+    // Steps 1 & 2 are not relevant
+
+    // Step 3
+    value = value.trim_start_matches(HTML_SPACE_CHARACTERS);
+
+    // Step 4
+    match value.chars().nth(0) {
+        Some('0'..='9') => {},
+        _ => return LengthOrPercentageOrAuto::Auto,
+    }
+
+    // Steps 5 to 8
+    // We trim the string length to the minimum of:
+    // 1. the end of the string
+    // 2. the first occurence of a '%' (U+0025 PERCENT SIGN)
+    // 3. the second occurrence of a '.' (U+002E FULL STOP)
+    // 4. the occurrence of a character that is neither a digit nor '%' nor '.'
+    // Note: Step 7.4 is directly subsumed by FromStr::from_str
+    let mut end_index = value.len();
+    let (mut found_full_stop, mut found_percent) = (false, false);
+    for (i, ch) in value.chars().enumerate() {
+        match ch {
+            '0'..='9' => continue,
+            '%' => {
+                found_percent = true;
+                end_index = i;
+                break;
+            },
+            '.' if !found_full_stop => {
+                found_full_stop = true;
+                continue;
+            },
+            _ => {
+                end_index = i;
+                break;
+            },
+        }
+    }
+    value = &value[..end_index];
+
+    if found_percent {
+        let result: Result<f32, _> = FromStr::from_str(value);
+        match result {
+            Ok(number) => return LengthOrPercentageOrAuto::Percentage((number as f32) / 100.0),
+            Err(_) => return LengthOrPercentageOrAuto::Auto,
+        }
+    }
+
+    match FromStr::from_str(value) {
+        Ok(number) => LengthOrPercentageOrAuto::Length(Au::from_f64_px(number)),
+        Err(_) => LengthOrPercentageOrAuto::Auto,
+    }
+}
+
+/// A struct that uniquely identifies an element's attribute.
+#[derive(Clone, Debug)]
+#[cfg_attr(feature = "servo", derive(MallocSizeOf))]
+pub struct AttrIdentifier {
+    pub local_name: LocalName,
+    pub name: LocalName,
+    pub namespace: Namespace,
+    pub prefix: Option<Prefix>,
+}