servo/components/style/media_queries.rs

/* 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/. */

use std::ascii::AsciiExt;
use cssparser::parse_rule_list;
use cssparser::ast::*;
use cssparser::ast::ComponentValue::*;

use errors::{ErrorLoggerIterator, log_css_error};
use geom::size::TypedSize2D;
use selectors::ParserContext;
use stylesheets::{CSSRule, parse_style_rule, parse_nested_at_rule};
use namespaces::NamespaceMap;
use parsing_utils::{BufferedIter, ParserIter};
use properties::common_types::*;
use properties::longhands;
use servo_util::geometry::ViewportPx;
use url::Url;

pub struct MediaRule {
    pub media_queries: MediaQueryList,
    pub rules: Vec<CSSRule>,
}

pub struct MediaQueryList {
    media_queries: Vec<MediaQuery>
}

#[deriving(PartialEq, Eq, Copy)]
pub enum Range<T> {
    Min(T),
    Max(T),
    //Eq(T),    // FIXME: Implement parsing support for equality then re-enable this.
}

impl<T: Ord> Range<T> {
    fn evaluate(&self, value: T) -> bool {
        match *self {
            Range::Min(ref width) => { value >= *width },
            Range::Max(ref width) => { value <= *width },
            //Range::Eq(ref width) => { value == *width },
        }
    }
}

#[deriving(PartialEq, Eq, Copy)]
pub enum Expression {
    Width(Range<Au>),
}

#[deriving(PartialEq, Eq, Copy)]
pub enum Qualifier {
    Only,
    Not,
}

pub struct MediaQuery {
    qualifier: Option<Qualifier>,
    media_type: MediaQueryType,
    expressions: Vec<Expression>,
}

impl MediaQuery {
    pub fn new(qualifier: Option<Qualifier>, media_type: MediaQueryType,
               expressions: Vec<Expression>) -> MediaQuery {
        MediaQuery {
            qualifier: qualifier,
            media_type: media_type,
            expressions: expressions,
        }
    }
}

#[deriving(PartialEq, Eq, Copy)]
pub enum MediaQueryType {
    All,  // Always true
    MediaType(MediaType),
}

#[deriving(PartialEq, Eq, Copy)]
pub enum MediaType {
    Screen,
    Print,
    Unknown,
}

pub struct Device {
    pub media_type: MediaType,
    pub viewport_size: TypedSize2D<ViewportPx, f32>,
}

impl Device {
    pub fn new(media_type: MediaType, viewport_size: TypedSize2D<ViewportPx, f32>) -> Device {
        Device {
            media_type: media_type,
            viewport_size: viewport_size,
        }
    }
}

pub fn parse_media_rule(context: &ParserContext,
                        rule: AtRule,
                        parent_rules: &mut Vec<CSSRule>,
                        namespaces: &NamespaceMap,
                        base_url: &Url) {
    let media_queries = parse_media_query_list(rule.prelude.as_slice());
    let block = match rule.block {
        Some(block) => block,
        None => {
            log_css_error(rule.location, "Invalid @media rule");
            return
        }
    };
    let mut rules = vec!();
    for rule in ErrorLoggerIterator(parse_rule_list(block.into_iter())) {
        match rule {
            Rule::QualifiedRule(rule) => {
                parse_style_rule(context, rule, &mut rules, namespaces, base_url)
            }
            Rule::AtRule(rule) => parse_nested_at_rule(
                context,
                rule.name.as_slice().to_ascii_lower().as_slice(),
                rule,
                &mut rules,
                namespaces,
                base_url),
        }
    }
    parent_rules.push(CSSRule::Media(MediaRule {
        media_queries: media_queries,
        rules: rules,
    }))
}

fn parse_value_as_length(value: &ComponentValue) -> Result<Au, ()> {
    let length = try!(specified::Length::parse_non_negative(value));

    // http://dev.w3.org/csswg/mediaqueries3/ - Section 6
    // em units are relative to the initial font-size.
    let initial_font_size = longhands::font_size::get_initial_value();
    Ok(computed::compute_Au_with_font_size(length, initial_font_size, initial_font_size))
}

fn parse_media_query_expression(iter: ParserIter) -> Result<Expression, ()> {
    // Expect a parenthesis block with the condition
    match iter.next() {
        Some(&ParenthesisBlock(ref block)) => {
            let iter = &mut BufferedIter::new(block.as_slice().skip_whitespace());

            // Parse the variable (e.g. min-width)
            let variable = match iter.next() {
                Some(&Ident(ref value)) => value,
                _ => return Err(())
            };

            // Ensure a colon follows
            match iter.next() {
                Some(&Colon) => {},
                _ => return Err(())
            }

            // Retrieve the value
            let value = try!(iter.next_as_result());

            // TODO: Handle other media query types
            let expression = match variable.as_slice().to_ascii_lower().as_slice() {
                "min-width" => {
                    let au = try!(parse_value_as_length(value));
                    Expression::Width(Range::Min(au))
                }
                "max-width" => {
                    let au = try!(parse_value_as_length(value));
                    Expression::Width(Range::Max(au))
                }
                _ => return Err(())
            };

            if iter.is_eof() {
                Ok(expression)
            } else {
                Err(())
            }
        }
        _ => Err(())
    }
}

fn parse_media_query(iter: ParserIter) -> Result<MediaQuery, ()> {
    let mut expressions = vec!();

    // Check for optional 'only' or 'not'
    let qualifier = match iter.next() {
        Some(&Ident(ref value)) if value.as_slice().to_ascii_lower().as_slice() == "only" => Some(Qualifier::Only),
        Some(&Ident(ref value)) if value.as_slice().to_ascii_lower().as_slice() == "not" => Some(Qualifier::Not),
        Some(component_value) => {
            iter.push_back(component_value);
            None
        }
        None => return Err(()),        // Empty queries are invalid
    };

    // Check for media type
    let media_type = match iter.next() {
        Some(&Ident(ref value)) => {
            match value.as_slice().to_ascii_lower().as_slice() {
                "screen" => MediaQueryType::MediaType(MediaType::Screen),
                "print" => MediaQueryType::MediaType(MediaType::Print),
                "all" => MediaQueryType::All,
                _ => MediaQueryType::MediaType(MediaType::Unknown),       // Unknown media types never match
            }
        }
        Some(component_value) => {
            // Media type is only optional if qualifier is not specified.
            if qualifier.is_some() {
                return Err(());
            }
            iter.push_back(component_value);

            // If no qualifier and media type present, an expression should exist here
            let expression = try!(parse_media_query_expression(iter));
            expressions.push(expression);

            MediaQueryType::All
        }
        None => return Err(()),
    };

    // Parse any subsequent expressions
    loop {
        // Each expression should begin with and
        match iter.next() {
            Some(&Ident(ref value)) => {
                match value.as_slice().to_ascii_lower().as_slice() {
                    "and" => {
                        let expression = try!(parse_media_query_expression(iter));
                        expressions.push(expression);
                    }
                    _ => return Err(()),
                }
            }
            Some(component_value) => {
                iter.push_back(component_value);
                break;
            }
            None => break,
        }
    }

    Ok(MediaQuery::new(qualifier, media_type, expressions))
}

pub fn parse_media_query_list(input: &[ComponentValue]) -> MediaQueryList {
    let iter = &mut BufferedIter::new(input.skip_whitespace());
    let mut media_queries = vec!();

    if iter.is_eof() {
        media_queries.push(MediaQuery::new(None, MediaQueryType::All, vec!()));
    } else {
        loop {
            // Attempt to parse a media query.
            let media_query_result = parse_media_query(iter);

            // Skip until next query or end
            let mut trailing_tokens = false;
            let mut more_queries = false;
            loop {
                match iter.next() {
                    Some(&Comma) => {
                        more_queries = true;
                        break;
                    }
                    Some(_) => trailing_tokens = true,
                    None => break,
                }
            }

            // Add the media query if it was valid and no trailing tokens were found.
            // Otherwise, create a 'not all' media query, that will never match.
            let media_query = match (media_query_result, trailing_tokens) {
                (Ok(media_query), false) => media_query,
                _ => MediaQuery::new(Some(Qualifier::Not), MediaQueryType::All, vec!()),
            };
            media_queries.push(media_query);

            if !more_queries {
                break;
            }
        }
    }

    MediaQueryList { media_queries: media_queries }
}

impl MediaQueryList {
    pub fn evaluate(&self, device: &Device) -> bool {
        // Check if any queries match (OR condition)
        self.media_queries.iter().any(|mq| {
            // Check if media matches. Unknown media never matches.
            let media_match = match mq.media_type {
                MediaQueryType::MediaType(MediaType::Unknown) => false,
                MediaQueryType::MediaType(media_type) => media_type == device.media_type,
                MediaQueryType::All => true,
            };

            // Check if all conditions match (AND condition)
            let query_match = media_match && mq.expressions.iter().all(|expression| {
                match expression {
                    &Expression::Width(value) => value.evaluate(
                        Au::from_frac_px(device.viewport_size.to_untyped().width as f64)),
                }
            });

            // Apply the logical NOT qualifier to the result
            match mq.qualifier {
                Some(Qualifier::Not) => !query_match,
                _ => query_match,
            }
        })
    }
}

#[cfg(test)]
mod tests {
    use geom::size::TypedSize2D;
    use properties::common_types::*;
    use stylesheets::{iter_stylesheet_media_rules, iter_stylesheet_style_rules, Stylesheet};
    use selector_matching::StylesheetOrigin;
    use super::*;
    use url::Url;

    fn test_media_rule(css: &str, callback: |&MediaQueryList, &str|) {
        let url = Url::parse("http://localhost").unwrap();
        let stylesheet = Stylesheet::from_str(css, url,
                                              StylesheetOrigin::Author);
        let mut rule_count: int = 0;
        iter_stylesheet_media_rules(&stylesheet, |rule| {
            rule_count += 1;
            callback(&rule.media_queries, css);
        });
        assert!(rule_count > 0);
    }

    fn media_query_test(device: &Device, css: &str, expected_rule_count: int) {
        let url = Url::parse("http://localhost").unwrap();
        let ss = Stylesheet::from_str(css, url, StylesheetOrigin::Author);
        let mut rule_count: int = 0;
        iter_stylesheet_style_rules(&ss, device, |_| rule_count += 1);
        assert!(rule_count == expected_rule_count, css.into_string());
    }

    #[test]
    fn test_mq_empty() {
        test_media_rule("@media { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == None, css.into_string());
            assert!(q.media_type == MediaQueryType::All, css.into_string());
            assert!(q.expressions.len() == 0, css.into_string());
        });
    }

    #[test]
    fn test_mq_screen() {
        test_media_rule("@media screen { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == None, css.into_string());
            assert!(q.media_type == MediaQueryType::MediaType(MediaType::Screen), css.into_string());
            assert!(q.expressions.len() == 0, css.into_string());
        });

        test_media_rule("@media only screen { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == Some(Qualifier::Only), css.into_string());
            assert!(q.media_type == MediaQueryType::MediaType(MediaType::Screen), css.into_string());
            assert!(q.expressions.len() == 0, css.into_string());
        });

        test_media_rule("@media not screen { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == Some(Qualifier::Not), css.into_string());
            assert!(q.media_type == MediaQueryType::MediaType(MediaType::Screen), css.into_string());
            assert!(q.expressions.len() == 0, css.into_string());
        });
    }

    #[test]
    fn test_mq_print() {
        test_media_rule("@media print { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == None, css.into_string());
            assert!(q.media_type == MediaQueryType::MediaType(MediaType::Print), css.into_string());
            assert!(q.expressions.len() == 0, css.into_string());
        });

        test_media_rule("@media only print { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == Some(Qualifier::Only), css.into_string());
            assert!(q.media_type == MediaQueryType::MediaType(MediaType::Print), css.into_string());
            assert!(q.expressions.len() == 0, css.into_string());
        });

        test_media_rule("@media not print { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == Some(Qualifier::Not), css.into_string());
            assert!(q.media_type == MediaQueryType::MediaType(MediaType::Print), css.into_string());
            assert!(q.expressions.len() == 0, css.into_string());
        });
    }

    #[test]
    fn test_mq_unknown() {
        test_media_rule("@media fridge { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == None, css.into_string());
            assert!(q.media_type == MediaQueryType::MediaType(MediaType::Unknown), css.into_string());
            assert!(q.expressions.len() == 0, css.into_string());
        });

        test_media_rule("@media only glass { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == Some(Qualifier::Only), css.into_string());
            assert!(q.media_type == MediaQueryType::MediaType(MediaType::Unknown), css.into_string());
            assert!(q.expressions.len() == 0, css.into_string());
        });

        test_media_rule("@media not wood { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == Some(Qualifier::Not), css.into_string());
            assert!(q.media_type == MediaQueryType::MediaType(MediaType::Unknown), css.into_string());
            assert!(q.expressions.len() == 0, css.into_string());
        });
    }

    #[test]
    fn test_mq_all() {
        test_media_rule("@media all { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == None, css.into_string());
            assert!(q.media_type == MediaQueryType::All, css.into_string());
            assert!(q.expressions.len() == 0, css.into_string());
        });

        test_media_rule("@media only all { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == Some(Qualifier::Only), css.into_string());
            assert!(q.media_type == MediaQueryType::All, css.into_string());
            assert!(q.expressions.len() == 0, css.into_string());
        });

        test_media_rule("@media not all { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == Some(Qualifier::Not), css.into_string());
            assert!(q.media_type == MediaQueryType::All, css.into_string());
            assert!(q.expressions.len() == 0, css.into_string());
        });
    }

    #[test]
    fn test_mq_or() {
        test_media_rule("@media screen, print { }", |list, css| {
            assert!(list.media_queries.len() == 2, css.into_string());
            let q0 = &list.media_queries[0];
            assert!(q0.qualifier == None, css.into_string());
            assert!(q0.media_type == MediaQueryType::MediaType(MediaType::Screen), css.into_string());
            assert!(q0.expressions.len() == 0, css.into_string());

            let q1 = &list.media_queries[1];
            assert!(q1.qualifier == None, css.into_string());
            assert!(q1.media_type == MediaQueryType::MediaType(MediaType::Print), css.into_string());
            assert!(q1.expressions.len() == 0, css.into_string());
        });
    }

    #[test]
    fn test_mq_default_expressions() {
        test_media_rule("@media (min-width: 100px) { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == None, css.into_string());
            assert!(q.media_type == MediaQueryType::All, css.into_string());
            assert!(q.expressions.len() == 1, css.into_string());
            match q.expressions[0] {
                Expression::Width(Range::Min(w)) => assert!(w == Au::from_px(100)),
                _ => panic!("wrong expression type"),
            }
        });

        test_media_rule("@media (max-width: 43px) { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == None, css.into_string());
            assert!(q.media_type == MediaQueryType::All, css.into_string());
            assert!(q.expressions.len() == 1, css.into_string());
            match q.expressions[0] {
                Expression::Width(Range::Max(w)) => assert!(w == Au::from_px(43)),
                _ => panic!("wrong expression type"),
            }
        });
    }

    #[test]
    fn test_mq_expressions() {
        test_media_rule("@media screen and (min-width: 100px) { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == None, css.into_string());
            assert!(q.media_type == MediaQueryType::MediaType(MediaType::Screen), css.into_string());
            assert!(q.expressions.len() == 1, css.into_string());
            match q.expressions[0] {
                Expression::Width(Range::Min(w)) => assert!(w == Au::from_px(100)),
                _ => panic!("wrong expression type"),
            }
        });

        test_media_rule("@media print and (max-width: 43px) { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == None, css.into_string());
            assert!(q.media_type == MediaQueryType::MediaType(MediaType::Print), css.into_string());
            assert!(q.expressions.len() == 1, css.into_string());
            match q.expressions[0] {
                Expression::Width(Range::Max(w)) => assert!(w == Au::from_px(43)),
                _ => panic!("wrong expression type"),
            }
        });

        test_media_rule("@media fridge and (max-width: 52px) { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == None, css.into_string());
            assert!(q.media_type == MediaQueryType::MediaType(MediaType::Unknown), css.into_string());
            assert!(q.expressions.len() == 1, css.into_string());
            match q.expressions[0] {
                Expression::Width(Range::Max(w)) => assert!(w == Au::from_px(52)),
                _ => panic!("wrong expression type"),
            }
        });
    }

    #[test]
    fn test_mq_multiple_expressions() {
        test_media_rule("@media (min-width: 100px) and (max-width: 200px) { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == None, css.into_string());
            assert!(q.media_type == MediaQueryType::All, css.into_string());
            assert!(q.expressions.len() == 2, css.into_string());
            match q.expressions[0] {
                Expression::Width(Range::Min(w)) => assert!(w == Au::from_px(100)),
                _ => panic!("wrong expression type"),
            }
            match q.expressions[1] {
                Expression::Width(Range::Max(w)) => assert!(w == Au::from_px(200)),
                _ => panic!("wrong expression type"),
            }
        });

        test_media_rule("@media not screen and (min-width: 100px) and (max-width: 200px) { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == Some(Qualifier::Not), css.into_string());
            assert!(q.media_type == MediaQueryType::MediaType(MediaType::Screen), css.into_string());
            assert!(q.expressions.len() == 2, css.into_string());
            match q.expressions[0] {
                Expression::Width(Range::Min(w)) => assert!(w == Au::from_px(100)),
                _ => panic!("wrong expression type"),
            }
            match q.expressions[1] {
                Expression::Width(Range::Max(w)) => assert!(w == Au::from_px(200)),
                _ => panic!("wrong expression type"),
            }
        });
    }

    #[test]
    fn test_mq_malformed_expressions() {
        test_media_rule("@media (min-width: 100blah) and (max-width: 200px) { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == Some(Qualifier::Not), css.into_string());
            assert!(q.media_type == MediaQueryType::All, css.into_string());
            assert!(q.expressions.len() == 0, css.into_string());
        });

        test_media_rule("@media screen and (height: 200px) { }", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == Some(Qualifier::Not), css.into_string());
            assert!(q.media_type == MediaQueryType::All, css.into_string());
            assert!(q.expressions.len() == 0, css.into_string());
        });

        test_media_rule("@media (min-width: 30em foo bar) {}", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == Some(Qualifier::Not), css.into_string());
            assert!(q.media_type == MediaQueryType::All, css.into_string());
            assert!(q.expressions.len() == 0, css.into_string());
        });

        test_media_rule("@media not {}", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == Some(Qualifier::Not), css.into_string());
            assert!(q.media_type == MediaQueryType::All, css.into_string());
            assert!(q.expressions.len() == 0, css.into_string());
        });

        test_media_rule("@media not (min-width: 300px) {}", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == Some(Qualifier::Not), css.into_string());
            assert!(q.media_type == MediaQueryType::All, css.into_string());
            assert!(q.expressions.len() == 0, css.into_string());
        });

        test_media_rule("@media , {}", |list, css| {
            assert!(list.media_queries.len() == 1, css.into_string());
            let q = &list.media_queries[0];
            assert!(q.qualifier == Some(Qualifier::Not), css.into_string());
            assert!(q.media_type == MediaQueryType::All, css.into_string());
            assert!(q.expressions.len() == 0, css.into_string());
        });

        test_media_rule("@media screen 4px, print {}", |list, css| {
            assert!(list.media_queries.len() == 2, css.into_string());
            let q0 = &list.media_queries[0];
            assert!(q0.qualifier == Some(Qualifier::Not), css.into_string());
            assert!(q0.media_type == MediaQueryType::All, css.into_string());
            assert!(q0.expressions.len() == 0, css.into_string());
            let q1 = &list.media_queries[1];
            assert!(q1.qualifier == None, css.into_string());
            assert!(q1.media_type == MediaQueryType::MediaType(MediaType::Print), css.into_string());
            assert!(q1.expressions.len() == 0, css.into_string());
        });

        test_media_rule("@media screen, {}", |list, css| {
            assert!(list.media_queries.len() == 2, css.into_string());
            let q0 = &list.media_queries[0];
            assert!(q0.qualifier == None, css.into_string());
            assert!(q0.media_type == MediaQueryType::MediaType(MediaType::Screen), css.into_string());
            assert!(q0.expressions.len() == 0, css.into_string());
            let q1 = &list.media_queries[1];
            assert!(q1.qualifier == Some(Qualifier::Not), css.into_string());
            assert!(q1.media_type == MediaQueryType::All, css.into_string());
            assert!(q1.expressions.len() == 0, css.into_string());
        });
    }

    #[test]
    fn test_matching_simple() {
        let device = Device {
            media_type: MediaType::Screen,
            viewport_size: TypedSize2D(200.0, 100.0),
        };

        media_query_test(&device, "@media not all { a { color: red; } }", 0);
        media_query_test(&device, "@media not screen { a { color: red; } }", 0);
        media_query_test(&device, "@media not print { a { color: red; } }", 1);

        media_query_test(&device, "@media unknown { a { color: red; } }", 0);
        media_query_test(&device, "@media not unknown { a { color: red; } }", 1);

        media_query_test(&device, "@media { a { color: red; } }", 1);
        media_query_test(&device, "@media screen { a { color: red; } }", 1);
        media_query_test(&device, "@media print { a { color: red; } }", 0);
    }

    #[test]
    fn test_matching_width() {
        let device = Device {
            media_type: MediaType::Screen,
            viewport_size: TypedSize2D(200.0, 100.0),
        };

        media_query_test(&device, "@media { a { color: red; } }", 1);

        media_query_test(&device, "@media (min-width: 50px) { a { color: red; } }", 1);
        media_query_test(&device, "@media (min-width: 150px) { a { color: red; } }", 1);
        media_query_test(&device, "@media (min-width: 300px) { a { color: red; } }", 0);

        media_query_test(&device, "@media screen and (min-width: 50px) { a { color: red; } }", 1);
        media_query_test(&device, "@media screen and (min-width: 150px) { a { color: red; } }", 1);
        media_query_test(&device, "@media screen and (min-width: 300px) { a { color: red; } }", 0);

        media_query_test(&device, "@media not screen and (min-width: 50px) { a { color: red; } }", 0);
        media_query_test(&device, "@media not screen and (min-width: 150px) { a { color: red; } }", 0);
        media_query_test(&device, "@media not screen and (min-width: 300px) { a { color: red; } }", 1);

        media_query_test(&device, "@media (max-width: 50px) { a { color: red; } }", 0);
        media_query_test(&device, "@media (max-width: 150px) { a { color: red; } }", 0);
        media_query_test(&device, "@media (max-width: 300px) { a { color: red; } }", 1);

        media_query_test(&device, "@media screen and (min-width: 50px) and (max-width: 100px) { a { color: red; } }", 0);
        media_query_test(&device, "@media screen and (min-width: 250px) and (max-width: 300px) { a { color: red; } }", 0);
        media_query_test(&device, "@media screen and (min-width: 50px) and (max-width: 250px) { a { color: red; } }", 1);

        media_query_test(&device, "@media not screen and (min-width: 50px) and (max-width: 100px) { a { color: red; } }", 1);
        media_query_test(&device, "@media not screen and (min-width: 250px) and (max-width: 300px) { a { color: red; } }", 1);
        media_query_test(&device, "@media not screen and (min-width: 50px) and (max-width: 250px) { a { color: red; } }", 0);

        media_query_test(&device, "@media not screen and (min-width: 3.1em) and (max-width: 6em) { a { color: red; } }", 1);
        media_query_test(&device, "@media not screen and (min-width: 16em) and (max-width: 19.75em) { a { color: red; } }", 1);
        media_query_test(&device, "@media not screen and (min-width: 3em) and (max-width: 250px) { a { color: red; } }", 0);
    }

    #[test]
    fn test_matching_invalid() {
        let device = Device {
            media_type: MediaType::Screen,
            viewport_size: TypedSize2D(200.0, 100.0),
        };

        media_query_test(&device, "@media fridge { a { color: red; } }", 0);
        media_query_test(&device, "@media screen and (height: 100px) { a { color: red; } }", 0);
        media_query_test(&device, "@media not print and (width: 100) { a { color: red; } }", 0);
    }
}