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)]
34#[typed(todo_derive_fields)]
35pub struct Rect<T>(pub T, pub T, pub T, pub T);
36
37impl<T> Rect<T> {
38    /// Returns a new `Rect<T>` value.
39    pub fn new(first: T, second: T, third: T, fourth: T) -> Self {
40        Rect(first, second, third, fourth)
41    }
42}
43
44impl<T> Rect<T>
45where
46    T: Clone,
47{
48    /// Returns a rect with all the values equal to `v`.
49    pub fn all(v: T) -> Self {
50        Rect::new(v.clone(), v.clone(), v.clone(), v)
51    }
52
53    /// Parses a new `Rect<T>` value with the given parse function.
54    pub fn parse_with<'i, 't, Parse>(
55        context: &ParserContext,
56        input: &mut Parser<'i, 't>,
57        parse: Parse,
58    ) -> Result<Self, ParseError<'i>>
59    where
60        Parse: Fn(&ParserContext, &mut Parser<'i, 't>) -> Result<T, ParseError<'i>>,
61    {
62        let first = parse(context, input)?;
63        let second = if let Ok(second) = input.try_parse(|i| parse(context, i)) {
64            second
65        } else {
66            // <first>
67            return Ok(Self::new(
68                first.clone(),
69                first.clone(),
70                first.clone(),
71                first,
72            ));
73        };
74        let third = if let Ok(third) = input.try_parse(|i| parse(context, i)) {
75            third
76        } else {
77            // <first> <second>
78            return Ok(Self::new(first.clone(), second.clone(), first, second));
79        };
80        let fourth = if let Ok(fourth) = input.try_parse(|i| parse(context, i)) {
81            fourth
82        } else {
83            // <first> <second> <third>
84            return Ok(Self::new(first, second.clone(), third, second));
85        };
86        // <first> <second> <third> <fourth>
87        Ok(Self::new(first, second, third, fourth))
88    }
89
90    /// Parses a new `Rect<T>` value which all components must be specified, with the given parse
91    /// function.
92    pub fn parse_all_components_with<'i, 't, Parse>(
93        context: &ParserContext,
94        input: &mut Parser<'i, 't>,
95        parse: Parse,
96    ) -> Result<Self, ParseError<'i>>
97    where
98        Parse: Fn(&ParserContext, &mut Parser<'i, 't>) -> Result<T, ParseError<'i>>,
99    {
100        let first = parse(context, input)?;
101        let second = parse(context, input)?;
102        let third = parse(context, input)?;
103        let fourth = parse(context, input)?;
104        // <first> <second> <third> <fourth>
105        Ok(Self::new(first, second, third, fourth))
106    }
107}
108
109impl<T> Parse for Rect<T>
110where
111    T: Clone + Parse,
112{
113    #[inline]
114    fn parse<'i, 't>(
115        context: &ParserContext,
116        input: &mut Parser<'i, 't>,
117    ) -> Result<Self, ParseError<'i>> {
118        Self::parse_with(context, input, T::parse)
119    }
120}
121
122impl<T> ToCss for Rect<T>
123where
124    T: PartialEq + ToCss,
125{
126    fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
127    where
128        W: Write,
129    {
130        self.0.to_css(dest)?;
131        let same_vertical = self.0 == self.2;
132        let same_horizontal = self.1 == self.3;
133        if same_vertical && same_horizontal && self.0 == self.1 {
134            return Ok(());
135        }
136        dest.write_char(' ')?;
137        self.1.to_css(dest)?;
138        if same_vertical && same_horizontal {
139            return Ok(());
140        }
141        dest.write_char(' ')?;
142        self.2.to_css(dest)?;
143        if same_horizontal {
144            return Ok(());
145        }
146        dest.write_char(' ')?;
147        self.3.to_css(dest)
148    }
149}
style/values/generics/rect.rs

style/values/generics/
rect.rs
