style/values/generics/
rect.rs

1/* This Source Code Form is subject to the terms of the Mozilla Public
2 * License, v. 2.0. If a copy of the MPL was not distributed with this
3 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
4
5//! Generic types for CSS values that are composed of four sides.
6
7use crate::parser::{Parse, ParserContext};
8use cssparser::Parser;
9use std::fmt::{self, Write};
10use style_traits::{CssWriter, ParseError, ToCss};
11
12/// A CSS value made of four components, where its `ToCss` impl will try to
13/// serialize as few components as possible, like for example in `border-width`.
14#[derive(
15    Animate,
16    Clone,
17    ComputeSquaredDistance,
18    Copy,
19    Debug,
20    Deserialize,
21    MallocSizeOf,
22    PartialEq,
23    SpecifiedValueInfo,
24    Serialize,
25    ToAnimatedValue,
26    ToAnimatedZero,
27    ToComputedValue,
28    ToResolvedValue,
29    ToShmem,
30)]
31#[repr(C)]
32pub struct Rect<T>(pub T, pub T, pub T, pub T);
33
34impl<T> Rect<T> {
35    /// Returns a new `Rect<T>` value.
36    pub fn new(first: T, second: T, third: T, fourth: T) -> Self {
37        Rect(first, second, third, fourth)
38    }
39}
40
41impl<T> Rect<T>
42where
43    T: Clone,
44{
45    /// Returns a rect with all the values equal to `v`.
46    pub fn all(v: T) -> Self {
47        Rect::new(v.clone(), v.clone(), v.clone(), v)
48    }
49
50    /// Parses a new `Rect<T>` value with the given parse function.
51    pub fn parse_with<'i, 't, Parse>(
52        context: &ParserContext,
53        input: &mut Parser<'i, 't>,
54        parse: Parse,
55    ) -> Result<Self, ParseError<'i>>
56    where
57        Parse: Fn(&ParserContext, &mut Parser<'i, 't>) -> Result<T, ParseError<'i>>,
58    {
59        let first = parse(context, input)?;
60        let second = if let Ok(second) = input.try_parse(|i| parse(context, i)) {
61            second
62        } else {
63            // <first>
64            return Ok(Self::new(
65                first.clone(),
66                first.clone(),
67                first.clone(),
68                first,
69            ));
70        };
71        let third = if let Ok(third) = input.try_parse(|i| parse(context, i)) {
72            third
73        } else {
74            // <first> <second>
75            return Ok(Self::new(first.clone(), second.clone(), first, second));
76        };
77        let fourth = if let Ok(fourth) = input.try_parse(|i| parse(context, i)) {
78            fourth
79        } else {
80            // <first> <second> <third>
81            return Ok(Self::new(first, second.clone(), third, second));
82        };
83        // <first> <second> <third> <fourth>
84        Ok(Self::new(first, second, third, fourth))
85    }
86
87    /// Parses a new `Rect<T>` value which all components must be specified, with the given parse
88    /// function.
89    pub fn parse_all_components_with<'i, 't, Parse>(
90        context: &ParserContext,
91        input: &mut Parser<'i, 't>,
92        parse: Parse,
93    ) -> Result<Self, ParseError<'i>>
94    where
95        Parse: Fn(&ParserContext, &mut Parser<'i, 't>) -> Result<T, ParseError<'i>>,
96    {
97        let first = parse(context, input)?;
98        let second = parse(context, input)?;
99        let third = parse(context, input)?;
100        let fourth = parse(context, input)?;
101        // <first> <second> <third> <fourth>
102        Ok(Self::new(first, second, third, fourth))
103    }
104}
105
106impl<T> Parse for Rect<T>
107where
108    T: Clone + Parse,
109{
110    #[inline]
111    fn parse<'i, 't>(
112        context: &ParserContext,
113        input: &mut Parser<'i, 't>,
114    ) -> Result<Self, ParseError<'i>> {
115        Self::parse_with(context, input, T::parse)
116    }
117}
118
119impl<T> ToCss for Rect<T>
120where
121    T: PartialEq + ToCss,
122{
123    fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
124    where
125        W: Write,
126    {
127        self.0.to_css(dest)?;
128        let same_vertical = self.0 == self.2;
129        let same_horizontal = self.1 == self.3;
130        if same_vertical && same_horizontal && self.0 == self.1 {
131            return Ok(());
132        }
133        dest.write_char(' ')?;
134        self.1.to_css(dest)?;
135        if same_vertical && same_horizontal {
136            return Ok(());
137        }
138        dest.write_char(' ')?;
139        self.2.to_css(dest)?;
140        if same_horizontal {
141            return Ok(());
142        }
143        dest.write_char(' ')?;
144        self.3.to_css(dest)
145    }
146}
style/values/generics/rect.rs

style/values/generics/
rect.rs
