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::derives::*;
8use crate::parser::{Parse, ParserContext};
9use cssparser::Parser;
10use std::fmt::{self, Write};
11use style_traits::{CssWriter, ParseError, ToCss};
12
13/// A CSS value made of four components, where its `ToCss` impl will try to
14/// serialize as few components as possible, like for example in `border-width`.
15#[derive(
16    Animate,
17    Clone,
18    ComputeSquaredDistance,
19    Copy,
20    Debug,
21    Deserialize,
22    MallocSizeOf,
23    PartialEq,
24    SpecifiedValueInfo,
25    Serialize,
26    ToAnimatedValue,
27    ToAnimatedZero,
28    ToComputedValue,
29    ToResolvedValue,
30    ToShmem,
31    ToTyped,
32)]
33#[repr(C)]
34pub struct Rect<T>(pub T, pub T, pub T, pub T);
35
36impl<T> Rect<T> {
37    /// Returns a new `Rect<T>` value.
38    pub fn new(first: T, second: T, third: T, fourth: T) -> Self {
39        Rect(first, second, third, fourth)
40    }
41}
42
43impl<T> Rect<T>
44where
45    T: Clone,
46{
47    /// Returns a rect with all the values equal to `v`.
48    pub fn all(v: T) -> Self {
49        Rect::new(v.clone(), v.clone(), v.clone(), v)
50    }
51
52    /// Parses a new `Rect<T>` value with the given parse function.
53    pub fn parse_with<'i, 't, Parse>(
54        context: &ParserContext,
55        input: &mut Parser<'i, 't>,
56        parse: Parse,
57    ) -> Result<Self, ParseError<'i>>
58    where
59        Parse: Fn(&ParserContext, &mut Parser<'i, 't>) -> Result<T, ParseError<'i>>,
60    {
61        let first = parse(context, input)?;
62        let second = if let Ok(second) = input.try_parse(|i| parse(context, i)) {
63            second
64        } else {
65            // <first>
66            return Ok(Self::new(
67                first.clone(),
68                first.clone(),
69                first.clone(),
70                first,
71            ));
72        };
73        let third = if let Ok(third) = input.try_parse(|i| parse(context, i)) {
74            third
75        } else {
76            // <first> <second>
77            return Ok(Self::new(first.clone(), second.clone(), first, second));
78        };
79        let fourth = if let Ok(fourth) = input.try_parse(|i| parse(context, i)) {
80            fourth
81        } else {
82            // <first> <second> <third>
83            return Ok(Self::new(first, second.clone(), third, second));
84        };
85        // <first> <second> <third> <fourth>
86        Ok(Self::new(first, second, third, fourth))
87    }
88
89    /// Parses a new `Rect<T>` value which all components must be specified, with the given parse
90    /// function.
91    pub fn parse_all_components_with<'i, 't, Parse>(
92        context: &ParserContext,
93        input: &mut Parser<'i, 't>,
94        parse: Parse,
95    ) -> Result<Self, ParseError<'i>>
96    where
97        Parse: Fn(&ParserContext, &mut Parser<'i, 't>) -> Result<T, ParseError<'i>>,
98    {
99        let first = parse(context, input)?;
100        let second = parse(context, input)?;
101        let third = parse(context, input)?;
102        let fourth = parse(context, input)?;
103        // <first> <second> <third> <fourth>
104        Ok(Self::new(first, second, third, fourth))
105    }
106}
107
108impl<T> Parse for Rect<T>
109where
110    T: Clone + Parse,
111{
112    #[inline]
113    fn parse<'i, 't>(
114        context: &ParserContext,
115        input: &mut Parser<'i, 't>,
116    ) -> Result<Self, ParseError<'i>> {
117        Self::parse_with(context, input, T::parse)
118    }
119}
120
121impl<T> ToCss for Rect<T>
122where
123    T: PartialEq + ToCss,
124{
125    fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
126    where
127        W: Write,
128    {
129        self.0.to_css(dest)?;
130        let same_vertical = self.0 == self.2;
131        let same_horizontal = self.1 == self.3;
132        if same_vertical && same_horizontal && self.0 == self.1 {
133            return Ok(());
134        }
135        dest.write_char(' ')?;
136        self.1.to_css(dest)?;
137        if same_vertical && same_horizontal {
138            return Ok(());
139        }
140        dest.write_char(' ')?;
141        self.2.to_css(dest)?;
142        if same_horizontal {
143            return Ok(());
144        }
145        dest.write_char(' ')?;
146        self.3.to_css(dest)
147    }
148}
style/values/generics/rect.rs

style/values/generics/
rect.rs
