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    ToTyped,
31)]
32#[repr(C)]
33pub struct Rect<T>(pub T, pub T, pub T, pub T);
34
35impl<T> Rect<T> {
36    /// Returns a new `Rect<T>` value.
37    pub fn new(first: T, second: T, third: T, fourth: T) -> Self {
38        Rect(first, second, third, fourth)
39    }
40}
41
42impl<T> Rect<T>
43where
44    T: Clone,
45{
46    /// Returns a rect with all the values equal to `v`.
47    pub fn all(v: T) -> Self {
48        Rect::new(v.clone(), v.clone(), v.clone(), v)
49    }
50
51    /// Parses a new `Rect<T>` value with the given parse function.
52    pub fn parse_with<'i, 't, Parse>(
53        context: &ParserContext,
54        input: &mut Parser<'i, 't>,
55        parse: Parse,
56    ) -> Result<Self, ParseError<'i>>
57    where
58        Parse: Fn(&ParserContext, &mut Parser<'i, 't>) -> Result<T, ParseError<'i>>,
59    {
60        let first = parse(context, input)?;
61        let second = if let Ok(second) = input.try_parse(|i| parse(context, i)) {
62            second
63        } else {
64            // <first>
65            return Ok(Self::new(
66                first.clone(),
67                first.clone(),
68                first.clone(),
69                first,
70            ));
71        };
72        let third = if let Ok(third) = input.try_parse(|i| parse(context, i)) {
73            third
74        } else {
75            // <first> <second>
76            return Ok(Self::new(first.clone(), second.clone(), first, second));
77        };
78        let fourth = if let Ok(fourth) = input.try_parse(|i| parse(context, i)) {
79            fourth
80        } else {
81            // <first> <second> <third>
82            return Ok(Self::new(first, second.clone(), third, second));
83        };
84        // <first> <second> <third> <fourth>
85        Ok(Self::new(first, second, third, fourth))
86    }
87
88    /// Parses a new `Rect<T>` value which all components must be specified, with the given parse
89    /// function.
90    pub fn parse_all_components_with<'i, 't, Parse>(
91        context: &ParserContext,
92        input: &mut Parser<'i, 't>,
93        parse: Parse,
94    ) -> Result<Self, ParseError<'i>>
95    where
96        Parse: Fn(&ParserContext, &mut Parser<'i, 't>) -> Result<T, ParseError<'i>>,
97    {
98        let first = parse(context, input)?;
99        let second = parse(context, input)?;
100        let third = parse(context, input)?;
101        let fourth = parse(context, input)?;
102        // <first> <second> <third> <fourth>
103        Ok(Self::new(first, second, third, fourth))
104    }
105}
106
107impl<T> Parse for Rect<T>
108where
109    T: Clone + Parse,
110{
111    #[inline]
112    fn parse<'i, 't>(
113        context: &ParserContext,
114        input: &mut Parser<'i, 't>,
115    ) -> Result<Self, ParseError<'i>> {
116        Self::parse_with(context, input, T::parse)
117    }
118}
119
120impl<T> ToCss for Rect<T>
121where
122    T: PartialEq + ToCss,
123{
124    fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
125    where
126        W: Write,
127    {
128        self.0.to_css(dest)?;
129        let same_vertical = self.0 == self.2;
130        let same_horizontal = self.1 == self.3;
131        if same_vertical && same_horizontal && self.0 == self.1 {
132            return Ok(());
133        }
134        dest.write_char(' ')?;
135        self.1.to_css(dest)?;
136        if same_vertical && same_horizontal {
137            return Ok(());
138        }
139        dest.write_char(' ')?;
140        self.2.to_css(dest)?;
141        if same_horizontal {
142            return Ok(());
143        }
144        dest.write_char(' ')?;
145        self.3.to_css(dest)
146    }
147}
style/values/generics/rect.rs

style/values/generics/
rect.rs
