/
media_queries.rs
768 lines (682 loc) · 28.8 KB
/
media_queries.rs
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/* 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 http://mozilla.org/MPL/2.0/. */
//! Gecko's media-query device and expression representation.
use app_units::AU_PER_PX;
use app_units::Au;
use context::QuirksMode;
use cssparser::{CssStringWriter, Parser, RGBA, Token, BasicParseError};
use euclid::ScaleFactor;
use euclid::Size2D;
use font_metrics::get_metrics_provider_for_product;
use gecko::values::convert_nscolor_to_rgba;
use gecko_bindings::bindings;
use gecko_bindings::structs;
use gecko_bindings::structs::{nsCSSKeyword, nsCSSProps_KTableEntry, nsCSSValue, nsCSSUnit};
use gecko_bindings::structs::{nsMediaExpression_Range, nsMediaFeature};
use gecko_bindings::structs::{nsMediaFeature_ValueType, nsMediaFeature_RangeType, nsMediaFeature_RequirementFlags};
use gecko_bindings::structs::{nsPresContext, RawGeckoPresContextOwned};
use gecko_bindings::structs::nsIAtom;
use media_queries::MediaType;
use parser::ParserContext;
use properties::{ComputedValues, StyleBuilder};
use properties::longhands::font_size;
use rule_cache::RuleCacheConditions;
use servo_arc::Arc;
use std::cell::RefCell;
use std::fmt::{self, Write};
use std::sync::atomic::{AtomicBool, AtomicIsize, Ordering};
use str::starts_with_ignore_ascii_case;
use string_cache::Atom;
use style_traits::{CSSPixel, DevicePixel};
use style_traits::{ToCss, ParseError, StyleParseError};
use style_traits::viewport::ViewportConstraints;
use values::{CSSFloat, CustomIdent, serialize_dimension};
use values::computed::{self, ToComputedValue};
use values::specified::Length;
/// The `Device` in Gecko wraps a pres context, has a default values computed,
/// and contains all the viewport rule state.
pub struct Device {
/// NB: The pres context lifetime is tied to the styleset, who owns the
/// stylist, and thus the `Device`, so having a raw pres context pointer
/// here is fine.
pres_context: RawGeckoPresContextOwned,
default_values: Arc<ComputedValues>,
/// The font size of the root element
/// This is set when computing the style of the root
/// element, and used for rem units in other elements.
///
/// When computing the style of the root element, there can't be any
/// other style being computed at the same time, given we need the style of
/// the parent to compute everything else. So it is correct to just use
/// a relaxed atomic here.
root_font_size: AtomicIsize,
/// Whether any styles computed in the document relied on the root font-size
/// by using rem units.
used_root_font_size: AtomicBool,
/// Whether any styles computed in the document relied on the viewport size
/// by using vw/vh/vmin/vmax units.
used_viewport_size: AtomicBool,
}
unsafe impl Sync for Device {}
unsafe impl Send for Device {}
impl Device {
/// Trivially constructs a new `Device`.
pub fn new(pres_context: RawGeckoPresContextOwned) -> Self {
assert!(!pres_context.is_null());
Device {
pres_context: pres_context,
default_values: ComputedValues::default_values(unsafe { &*pres_context }),
// FIXME(bz): Seems dubious?
root_font_size: AtomicIsize::new(font_size::get_initial_value().0.to_i32_au() as isize),
used_root_font_size: AtomicBool::new(false),
used_viewport_size: AtomicBool::new(false),
}
}
/// Tells the device that a new viewport rule has been found, and stores the
/// relevant viewport constraints.
pub fn account_for_viewport_rule(
&mut self,
_constraints: &ViewportConstraints
) {
unreachable!("Gecko doesn't support @viewport");
}
/// Returns the default computed values as a reference, in order to match
/// Servo.
pub fn default_computed_values(&self) -> &ComputedValues {
&self.default_values
}
/// Returns the default computed values as an `Arc`.
pub fn default_computed_values_arc(&self) -> &Arc<ComputedValues> {
&self.default_values
}
/// Get the font size of the root element (for rem)
pub fn root_font_size(&self) -> Au {
self.used_root_font_size.store(true, Ordering::Relaxed);
Au::new(self.root_font_size.load(Ordering::Relaxed) as i32)
}
/// Set the font size of the root element (for rem)
pub fn set_root_font_size(&self, size: Au) {
self.root_font_size.store(size.0 as isize, Ordering::Relaxed)
}
/// Gets the pres context associated with this document.
pub fn pres_context(&self) -> &nsPresContext {
unsafe { &*self.pres_context }
}
/// Recreates the default computed values.
pub fn reset_computed_values(&mut self) {
self.default_values = ComputedValues::default_values(self.pres_context());
}
/// Rebuild all the cached data.
pub fn rebuild_cached_data(&mut self) {
self.reset_computed_values();
self.used_root_font_size.store(false, Ordering::Relaxed);
self.used_viewport_size.store(false, Ordering::Relaxed);
}
/// Returns whether we ever looked up the root font size of the Device.
pub fn used_root_font_size(&self) -> bool {
self.used_root_font_size.load(Ordering::Relaxed)
}
/// Recreates all the temporary state that the `Device` stores.
///
/// This includes the viewport override from `@viewport` rules, and also the
/// default computed values.
pub fn reset(&mut self) {
self.reset_computed_values();
}
/// Returns the current media type of the device.
pub fn media_type(&self) -> MediaType {
unsafe {
// Gecko allows emulating random media with mIsEmulatingMedia and
// mMediaEmulated.
let context = self.pres_context();
let medium_to_use = if context.mIsEmulatingMedia() != 0 {
context.mMediaEmulated.raw::<nsIAtom>()
} else {
context.mMedium
};
MediaType(CustomIdent(Atom::from(medium_to_use)))
}
}
/// Returns the current viewport size in app units.
pub fn au_viewport_size(&self) -> Size2D<Au> {
let area = &self.pres_context().mVisibleArea;
Size2D::new(Au(area.width), Au(area.height))
}
/// Returns the current viewport size in app units, recording that it's been
/// used for viewport unit resolution.
pub fn au_viewport_size_for_viewport_unit_resolution(&self) -> Size2D<Au> {
self.used_viewport_size.store(true, Ordering::Relaxed);
self.au_viewport_size()
}
/// Returns whether we ever looked up the viewport size of the Device.
pub fn used_viewport_size(&self) -> bool {
self.used_viewport_size.load(Ordering::Relaxed)
}
/// Returns the device pixel ratio.
pub fn device_pixel_ratio(&self) -> ScaleFactor<f32, CSSPixel, DevicePixel> {
let override_dppx = self.pres_context().mOverrideDPPX;
if override_dppx > 0.0 { return ScaleFactor::new(override_dppx); }
let au_per_dpx = self.pres_context().mCurAppUnitsPerDevPixel as f32;
let au_per_px = AU_PER_PX as f32;
ScaleFactor::new(au_per_px / au_per_dpx)
}
/// Returns whether document colors are enabled.
pub fn use_document_colors(&self) -> bool {
self.pres_context().mUseDocumentColors() != 0
}
/// Returns the default background color.
pub fn default_background_color(&self) -> RGBA {
convert_nscolor_to_rgba(self.pres_context().mBackgroundColor)
}
/// Applies text zoom to a font-size or line-height value (see nsStyleFont::ZoomText).
pub fn zoom_text(&self, size: Au) -> Au {
size.scale_by(self.pres_context().mEffectiveTextZoom)
}
/// Un-apply text zoom (see nsStyleFont::UnzoomText).
pub fn unzoom_text(&self, size: Au) -> Au {
size.scale_by(1. / self.pres_context().mEffectiveTextZoom)
}
}
/// A expression for gecko contains a reference to the media feature, the value
/// the media query contained, and the range to evaluate.
#[derive(Clone, Debug)]
pub struct Expression {
feature: &'static nsMediaFeature,
value: Option<MediaExpressionValue>,
range: nsMediaExpression_Range
}
impl ToCss for Expression {
fn to_css<W>(&self, dest: &mut W) -> fmt::Result
where W: fmt::Write,
{
dest.write_str("(")?;
if (self.feature.mReqFlags & nsMediaFeature_RequirementFlags::eHasWebkitPrefix as u8) != 0 {
dest.write_str("-webkit-")?;
}
match self.range {
nsMediaExpression_Range::eMin => dest.write_str("min-")?,
nsMediaExpression_Range::eMax => dest.write_str("max-")?,
nsMediaExpression_Range::eEqual => {},
}
// NB: CssStringWriter not needed, feature names are under control.
write!(dest, "{}", Atom::from(unsafe { *self.feature.mName }))?;
if let Some(ref val) = self.value {
dest.write_str(": ")?;
val.to_css(dest, self)?;
}
dest.write_str(")")
}
}
impl PartialEq for Expression {
fn eq(&self, other: &Expression) -> bool {
self.feature.mName == other.feature.mName &&
self.value == other.value && self.range == other.range
}
}
/// A resolution.
#[derive(Clone, Debug, PartialEq)]
pub enum Resolution {
/// Dots per inch.
Dpi(CSSFloat),
/// Dots per pixel.
Dppx(CSSFloat),
/// Dots per centimeter.
Dpcm(CSSFloat),
}
impl Resolution {
fn to_dpi(&self) -> CSSFloat {
match *self {
Resolution::Dpi(f) => f,
Resolution::Dppx(f) => f * 96.0,
Resolution::Dpcm(f) => f * 2.54,
}
}
fn parse<'i, 't>(input: &mut Parser<'i, 't>) -> Result<Self, ParseError<'i>> {
let (value, unit) = match *input.next()? {
Token::Dimension { value, ref unit, .. } => {
(value, unit)
},
ref t => return Err(BasicParseError::UnexpectedToken(t.clone()).into()),
};
if value <= 0. {
return Err(StyleParseError::UnspecifiedError.into())
}
(match_ignore_ascii_case! { &unit,
"dpi" => Ok(Resolution::Dpi(value)),
"dppx" => Ok(Resolution::Dppx(value)),
"dpcm" => Ok(Resolution::Dpcm(value)),
_ => Err(())
}).map_err(|()| StyleParseError::UnexpectedDimension(unit.clone()).into())
}
}
impl ToCss for Resolution {
fn to_css<W>(&self, dest: &mut W) -> fmt::Result
where W: fmt::Write,
{
match *self {
Resolution::Dpi(v) => serialize_dimension(v, "dpi", dest),
Resolution::Dppx(v) => serialize_dimension(v, "dppx", dest),
Resolution::Dpcm(v) => serialize_dimension(v, "dpcm", dest),
}
}
}
/// A value found or expected in a media expression.
#[derive(Clone, Debug, PartialEq)]
pub enum MediaExpressionValue {
/// A length.
Length(Length),
/// A (non-negative) integer.
Integer(u32),
/// A floating point value.
Float(CSSFloat),
/// A boolean value, specified as an integer (i.e., either 0 or 1).
BoolInteger(bool),
/// Two integers separated by '/', with optional whitespace on either side
/// of the '/'.
IntRatio(u32, u32),
/// A resolution.
Resolution(Resolution),
/// An enumerated value, defined by the variant keyword table in the
/// feature's `mData` member.
Enumerated(i16),
/// An identifier.
///
/// TODO(emilio): Maybe atomize?
Ident(String),
}
impl MediaExpressionValue {
fn from_css_value(for_expr: &Expression, css_value: &nsCSSValue) -> Option<Self> {
use gecko::conversions::string_from_chars_pointer;
// NB: If there's a null value, that means that we don't support the
// feature.
if css_value.mUnit == nsCSSUnit::eCSSUnit_Null {
return None;
}
match for_expr.feature.mValueType {
nsMediaFeature_ValueType::eLength => {
debug_assert!(css_value.mUnit == nsCSSUnit::eCSSUnit_Pixel);
let pixels = css_value.float_unchecked();
Some(MediaExpressionValue::Length(Length::from_px(pixels)))
}
nsMediaFeature_ValueType::eInteger => {
let i = css_value.integer_unchecked();
debug_assert!(i >= 0);
Some(MediaExpressionValue::Integer(i as u32))
}
nsMediaFeature_ValueType::eFloat => {
debug_assert!(css_value.mUnit == nsCSSUnit::eCSSUnit_Number);
Some(MediaExpressionValue::Float(css_value.float_unchecked()))
}
nsMediaFeature_ValueType::eBoolInteger => {
debug_assert!(css_value.mUnit == nsCSSUnit::eCSSUnit_Integer);
let i = css_value.integer_unchecked();
debug_assert!(i == 0 || i == 1);
Some(MediaExpressionValue::BoolInteger(i == 1))
}
nsMediaFeature_ValueType::eResolution => {
debug_assert!(css_value.mUnit == nsCSSUnit::eCSSUnit_Inch);
Some(MediaExpressionValue::Resolution(Resolution::Dpi(css_value.float_unchecked())))
}
nsMediaFeature_ValueType::eEnumerated => {
let value = css_value.integer_unchecked() as i16;
Some(MediaExpressionValue::Enumerated(value))
}
nsMediaFeature_ValueType::eIdent => {
debug_assert!(css_value.mUnit == nsCSSUnit::eCSSUnit_Ident);
let string = unsafe {
let buffer = *css_value.mValue.mString.as_ref();
debug_assert!(!buffer.is_null());
string_from_chars_pointer(buffer.offset(1) as *const u16)
};
Some(MediaExpressionValue::Ident(string))
}
nsMediaFeature_ValueType::eIntRatio => {
let array = unsafe { css_value.array_unchecked() };
debug_assert_eq!(array.len(), 2);
let first = array[0].integer_unchecked();
let second = array[1].integer_unchecked();
debug_assert!(first >= 0 && second >= 0);
Some(MediaExpressionValue::IntRatio(first as u32, second as u32))
}
}
}
}
impl MediaExpressionValue {
fn to_css<W>(&self, dest: &mut W, for_expr: &Expression) -> fmt::Result
where W: fmt::Write,
{
match *self {
MediaExpressionValue::Length(ref l) => l.to_css(dest),
MediaExpressionValue::Integer(v) => v.to_css(dest),
MediaExpressionValue::Float(v) => v.to_css(dest),
MediaExpressionValue::BoolInteger(v) => {
dest.write_str(if v { "1" } else { "0" })
},
MediaExpressionValue::IntRatio(a, b) => {
a.to_css(dest)?;
dest.write_char('/')?;
b.to_css(dest)
},
MediaExpressionValue::Resolution(ref r) => r.to_css(dest),
MediaExpressionValue::Ident(ref ident) => {
CssStringWriter::new(dest).write_str(ident)
}
MediaExpressionValue::Enumerated(value) => unsafe {
use std::{slice, str};
use std::os::raw::c_char;
// NB: All the keywords on nsMediaFeatures are static,
// well-formed utf-8.
let mut length = 0;
let (keyword, _value) =
find_in_table(*for_expr.feature.mData.mKeywordTable.as_ref(),
|_kw, val| val == value)
.expect("Value not found in the keyword table?");
let buffer: *const c_char =
bindings::Gecko_CSSKeywordString(keyword, &mut length);
let buffer =
slice::from_raw_parts(buffer as *const u8, length as usize);
let string = str::from_utf8_unchecked(buffer);
dest.write_str(string)
}
}
}
}
fn find_feature<F>(mut f: F) -> Option<&'static nsMediaFeature>
where F: FnMut(&'static nsMediaFeature) -> bool,
{
unsafe {
let mut features = structs::nsMediaFeatures_features.as_ptr();
while !(*features).mName.is_null() {
if f(&*features) {
return Some(&*features);
}
features = features.offset(1);
}
}
None
}
unsafe fn find_in_table<F>(mut current_entry: *const nsCSSProps_KTableEntry,
mut f: F)
-> Option<(nsCSSKeyword, i16)>
where F: FnMut(nsCSSKeyword, i16) -> bool
{
loop {
let value = (*current_entry).mValue;
let keyword = (*current_entry).mKeyword;
if value == -1 {
return None; // End of the table.
}
if f(keyword, value) {
return Some((keyword, value));
}
current_entry = current_entry.offset(1);
}
}
fn parse_feature_value<'i, 't>(feature: &nsMediaFeature,
feature_value_type: nsMediaFeature_ValueType,
context: &ParserContext,
input: &mut Parser<'i, 't>)
-> Result<MediaExpressionValue, ParseError<'i>> {
let value = match feature_value_type {
nsMediaFeature_ValueType::eLength => {
let length = Length::parse_non_negative(context, input)?;
// FIXME(canaltinova): See bug 1396057. Gecko doesn't support calc
// inside media queries. This check is for temporarily remove it
// for parity with gecko. We should remove this check when we want
// to support it.
if let Length::Calc(_) = length {
return Err(StyleParseError::UnspecifiedError.into())
}
MediaExpressionValue::Length(length)
},
nsMediaFeature_ValueType::eInteger => {
// FIXME(emilio): We should use `Integer::parse` to handle `calc`
// properly in integer expressions. Note that calc is still not
// supported in media queries per FIXME above.
let i = input.expect_integer()?;
if i < 0 {
return Err(StyleParseError::UnspecifiedError.into())
}
MediaExpressionValue::Integer(i as u32)
}
nsMediaFeature_ValueType::eBoolInteger => {
let i = input.expect_integer()?;
if i < 0 || i > 1 {
return Err(StyleParseError::UnspecifiedError.into())
}
MediaExpressionValue::BoolInteger(i == 1)
}
nsMediaFeature_ValueType::eFloat => {
MediaExpressionValue::Float(input.expect_number()?)
}
nsMediaFeature_ValueType::eIntRatio => {
let a = input.expect_integer()?;
if a <= 0 {
return Err(StyleParseError::UnspecifiedError.into())
}
input.expect_delim('/')?;
let b = input.expect_integer()?;
if b <= 0 {
return Err(StyleParseError::UnspecifiedError.into())
}
MediaExpressionValue::IntRatio(a as u32, b as u32)
}
nsMediaFeature_ValueType::eResolution => {
MediaExpressionValue::Resolution(Resolution::parse(input)?)
}
nsMediaFeature_ValueType::eEnumerated => {
let keyword = input.expect_ident()?;
let keyword = unsafe {
bindings::Gecko_LookupCSSKeyword(keyword.as_bytes().as_ptr(),
keyword.len() as u32)
};
let first_table_entry: *const nsCSSProps_KTableEntry = unsafe {
*feature.mData.mKeywordTable.as_ref()
};
let value =
match unsafe { find_in_table(first_table_entry, |kw, _| kw == keyword) } {
Some((_kw, value)) => {
value
}
None => return Err(StyleParseError::UnspecifiedError.into()),
};
MediaExpressionValue::Enumerated(value)
}
nsMediaFeature_ValueType::eIdent => {
MediaExpressionValue::Ident(input.expect_ident()?.as_ref().to_owned())
}
};
Ok(value)
}
impl Expression {
/// Trivially construct a new expression.
fn new(feature: &'static nsMediaFeature,
value: Option<MediaExpressionValue>,
range: nsMediaExpression_Range) -> Self {
Expression {
feature: feature,
value: value,
range: range,
}
}
/// Parse a media expression of the form:
///
/// ```
/// (media-feature: media-value)
/// ```
pub fn parse<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
-> Result<Self, ParseError<'i>> {
input.expect_parenthesis_block().map_err(|err|
match err {
BasicParseError::UnexpectedToken(t) => StyleParseError::ExpectedIdentifier(t),
_ => StyleParseError::UnspecifiedError,
}
)?;
input.parse_nested_block(|input| {
// FIXME: remove extra indented block when lifetimes are non-lexical
let feature;
let range;
{
let ident = input.expect_ident().map_err(|err|
match err {
BasicParseError::UnexpectedToken(t) => StyleParseError::ExpectedIdentifier(t),
_ => StyleParseError::UnspecifiedError,
}
)?;
let mut flags = 0;
let result = {
let mut feature_name = &**ident;
if unsafe { structs::StylePrefs_sWebkitPrefixedAliasesEnabled } &&
starts_with_ignore_ascii_case(feature_name, "-webkit-") {
feature_name = &feature_name[8..];
flags |= nsMediaFeature_RequirementFlags::eHasWebkitPrefix as u8;
if unsafe { structs::StylePrefs_sWebkitDevicePixelRatioEnabled } {
flags |= nsMediaFeature_RequirementFlags::eWebkitDevicePixelRatioPrefEnabled as u8;
}
}
let range = if starts_with_ignore_ascii_case(feature_name, "min-") {
feature_name = &feature_name[4..];
nsMediaExpression_Range::eMin
} else if starts_with_ignore_ascii_case(feature_name, "max-") {
feature_name = &feature_name[4..];
nsMediaExpression_Range::eMax
} else {
nsMediaExpression_Range::eEqual
};
let atom = Atom::from(feature_name);
match find_feature(|f| atom.as_ptr() == unsafe { *f.mName }) {
Some(f) => Ok((f, range)),
None => Err(()),
}
};
match result {
Ok((f, r)) => {
feature = f;
range = r;
},
Err(()) => {
return Err(StyleParseError::MediaQueryExpectedFeatureName(ident.clone()).into())
},
}
if (feature.mReqFlags & !flags) != 0 {
return Err(StyleParseError::MediaQueryExpectedFeatureName(ident.clone()).into());
}
if range != nsMediaExpression_Range::eEqual &&
feature.mRangeType != nsMediaFeature_RangeType::eMinMaxAllowed {
return Err(StyleParseError::MediaQueryExpectedFeatureName(ident.clone()).into());
}
}
// If there's no colon, this is a media query of the form
// '(<feature>)', that is, there's no value specified.
//
// Gecko doesn't allow ranged expressions without a value, so just
// reject them here too.
if input.try(|i| i.expect_colon()).is_err() {
if range != nsMediaExpression_Range::eEqual {
return Err(StyleParseError::RangedExpressionWithNoValue.into())
}
return Ok(Expression::new(feature, None, range));
}
let value = parse_feature_value(feature,
feature.mValueType,
context, input).map_err(|_|
StyleParseError::MediaQueryExpectedFeatureValue
)?;
Ok(Expression::new(feature, Some(value), range))
})
}
/// Returns whether this media query evaluates to true for the given device.
pub fn matches(&self, device: &Device, quirks_mode: QuirksMode) -> bool {
let mut css_value = nsCSSValue::null();
unsafe {
(self.feature.mGetter.unwrap())(device.pres_context,
self.feature,
&mut css_value)
};
let value = match MediaExpressionValue::from_css_value(self, &css_value) {
Some(v) => v,
None => return false,
};
self.evaluate_against(device, &value, quirks_mode)
}
fn evaluate_against(&self,
device: &Device,
actual_value: &MediaExpressionValue,
quirks_mode: QuirksMode)
-> bool {
use self::MediaExpressionValue::*;
use std::cmp::Ordering;
debug_assert!(self.range == nsMediaExpression_Range::eEqual ||
self.feature.mRangeType == nsMediaFeature_RangeType::eMinMaxAllowed,
"Whoops, wrong range");
let default_values = device.default_computed_values();
let provider = get_metrics_provider_for_product();
// http://dev.w3.org/csswg/mediaqueries3/#units
// em units are relative to the initial font-size.
let mut conditions = RuleCacheConditions::default();
let context = computed::Context {
is_root_element: false,
builder: StyleBuilder::for_derived_style(device, default_values, None, None),
font_metrics_provider: &provider,
cached_system_font: None,
in_media_query: true,
// TODO: pass the correct value here.
quirks_mode: quirks_mode,
for_smil_animation: false,
for_non_inherited_property: None,
rule_cache_conditions: RefCell::new(&mut conditions),
};
let required_value = match self.value {
Some(ref v) => v,
None => {
// If there's no value, always match unless it's a zero length
// or a zero integer or boolean.
return match *actual_value {
BoolInteger(v) => v,
Integer(v) => v != 0,
Length(ref l) => l.to_computed_value(&context).px() != 0.,
_ => true,
}
}
};
// FIXME(emilio): Handle the possible floating point errors?
let cmp = match (required_value, actual_value) {
(&Length(ref one), &Length(ref other)) => {
one.to_computed_value(&context).to_i32_au()
.cmp(&other.to_computed_value(&context).to_i32_au())
}
(&Integer(one), &Integer(ref other)) => one.cmp(other),
(&BoolInteger(one), &BoolInteger(ref other)) => one.cmp(other),
(&Float(one), &Float(ref other)) => one.partial_cmp(other).unwrap(),
(&IntRatio(one_num, one_den), &IntRatio(other_num, other_den)) => {
(one_num * other_den).partial_cmp(&(other_num * one_den)).unwrap()
}
(&Resolution(ref one), &Resolution(ref other)) => {
let actual_dpi = unsafe {
if (*device.pres_context).mOverrideDPPX > 0.0 {
self::Resolution::Dppx((*device.pres_context).mOverrideDPPX)
.to_dpi()
} else {
other.to_dpi()
}
};
one.to_dpi().partial_cmp(&actual_dpi).unwrap()
}
(&Ident(ref one), &Ident(ref other)) => {
debug_assert!(self.feature.mRangeType != nsMediaFeature_RangeType::eMinMaxAllowed);
return one == other;
}
(&Enumerated(one), &Enumerated(other)) => {
debug_assert!(self.feature.mRangeType != nsMediaFeature_RangeType::eMinMaxAllowed);
return one == other;
}
_ => unreachable!(),
};
cmp == Ordering::Equal || match self.range {
nsMediaExpression_Range::eMin => cmp == Ordering::Less,
nsMediaExpression_Range::eEqual => false,
nsMediaExpression_Range::eMax => cmp == Ordering::Greater,
}
}
}