yew_stdweb/virtual_dom/
vtext.rs

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
//! This module contains the implementation of a virtual text node `VText`.

use super::{AttrValue, VDiff, VNode};
use crate::html::{AnyScope, NodeRef};
use crate::utils::document;
use cfg_if::cfg_if;
use log::warn;
use std::cmp::PartialEq;
cfg_if! {
    if #[cfg(feature = "std_web")] {
        use stdweb::web::{Element, INode, TextNode};
    } else if #[cfg(feature = "web_sys")] {
        use web_sys::{Element, Text as TextNode};
    }
}

/// A type for a virtual
/// [`TextNode`](https://developer.mozilla.org/en-US/docs/Web/API/Document/createTextNode)
/// representation.
#[derive(Clone, Debug)]
pub struct VText {
    /// Contains a text of the node.
    pub text: AttrValue,
    /// A reference to the `TextNode`.
    pub reference: Option<TextNode>,
}

impl VText {
    /// Creates new virtual text node with a content.
    pub fn new(text: impl Into<AttrValue>) -> Self {
        VText {
            text: text.into(),
            reference: None,
        }
    }
}

impl VDiff for VText {
    /// Remove VText from parent.
    fn detach(&mut self, parent: &Element) {
        let node = self
            .reference
            .take()
            .expect("tried to remove not rendered VText from DOM");
        if parent.remove_child(&node).is_err() {
            warn!("Node not found to remove VText");
        }
    }

    /// Renders virtual node over existing `TextNode`, but only if value of text has changed.
    fn apply(
        &mut self,
        _parent_scope: &AnyScope,
        parent: &Element,
        next_sibling: NodeRef,
        ancestor: Option<VNode>,
    ) -> NodeRef {
        if let Some(mut ancestor) = ancestor {
            if let VNode::VText(mut vtext) = ancestor {
                self.reference = vtext.reference.take();
                let text_node = self
                    .reference
                    .clone()
                    .expect("Rendered VText nodes should have a ref");
                if self.text != vtext.text {
                    text_node.set_node_value(Some(&self.text));
                }

                return NodeRef::new(text_node.into());
            }

            ancestor.detach(parent);
        }

        let text_node = document().create_text_node(&self.text);
        super::insert_node(&text_node, parent, next_sibling.get());
        self.reference = Some(text_node.clone());
        NodeRef::new(text_node.into())
    }
}

impl PartialEq for VText {
    fn eq(&self, other: &VText) -> bool {
        self.text == other.text
    }
}

#[cfg(test)]
mod test {
    extern crate self as yew;

    use crate::html;

    #[cfg(feature = "wasm_test")]
    use wasm_bindgen_test::{wasm_bindgen_test as test, wasm_bindgen_test_configure};

    #[cfg(feature = "wasm_test")]
    wasm_bindgen_test_configure!(run_in_browser);

    #[test]
    fn text_as_root() {
        html! {
            "Text Node As Root"
        };

        html! {
            { "Text Node As Root" }
        };
    }
}

#[cfg(all(test, feature = "web_sys"))]
mod layout_tests {
    extern crate self as yew;

    use crate::html;
    use crate::virtual_dom::layout_tests::{diff_layouts, TestLayout};

    #[cfg(feature = "wasm_test")]
    use wasm_bindgen_test::{wasm_bindgen_test as test, wasm_bindgen_test_configure};

    #[cfg(feature = "wasm_test")]
    wasm_bindgen_test_configure!(run_in_browser);

    #[test]
    fn diff() {
        let layout1 = TestLayout {
            name: "1",
            node: html! { "a" },
            expected: "a",
        };

        let layout2 = TestLayout {
            name: "2",
            node: html! { "b" },
            expected: "b",
        };

        let layout3 = TestLayout {
            name: "3",
            node: html! {
                <>
                    {"a"}
                    {"b"}
                </>
            },
            expected: "ab",
        };

        let layout4 = TestLayout {
            name: "4",
            node: html! {
                <>
                    {"b"}
                    {"a"}
                </>
            },
            expected: "ba",
        };

        diff_layouts(vec![layout1, layout2, layout3, layout4]);
    }
}