dtoolkit 0.1.1

A library for parsing and manipulating Flattened Device Tree (FDT) blobs.
Documentation 
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

// Copyright 2025 Google LLC
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

#![cfg(feature = "write")]

use dtoolkit::model::{DeviceTree, DeviceTreeNode, DeviceTreeProperty};
use dtoolkit::{Node, Property};

#[test]
fn tree_creation() {
    let mut tree = DeviceTree::new();
    tree.root
        .add_property(DeviceTreeProperty::new("compatible", "test"));
    tree.root
        .add_property(DeviceTreeProperty::new("prop-u32", 1u32.to_be_bytes()));
    tree.root.add_child(
        DeviceTreeNode::builder("child-a")
            .property(DeviceTreeProperty::new("child-prop", "a\0"))
            .build(),
    );
    tree.root.add_child(
        DeviceTreeNode::builder("child-b")
            .property(DeviceTreeProperty::new("child-prop", "b\0"))
            .build(),
    );

    let root = &tree.root;
    assert_eq!(root.name(), "/");
    assert_eq!(root.properties().count(), 2);
    assert_eq!(root.children().count(), 2);

    let child_a = root.children().find(|c| c.name() == "child-a").unwrap();
    assert_eq!(child_a.property("child-prop").unwrap().as_str(), Ok("a"));

    let child_b = root.children().find(|c| c.name() == "child-b").unwrap();
    assert_eq!(child_b.property("child-prop").unwrap().as_str(), Ok("b"));
}

#[test]
fn tree_modification() {
    let mut tree = DeviceTree::new();

    // Add a child
    let child = DeviceTreeNode::new("child");
    tree.root.add_child(child);
    assert_eq!((&tree.root).children().count(), 1);

    // Add a property to the child
    let child = tree.root.child_mut("child").unwrap();
    child.add_property(DeviceTreeProperty::new("prop", "value\0"));
    assert_eq!((&*child).properties().count(), 1);

    // Find and modify the property
    let prop = tree
        .root
        .child_mut("child")
        .unwrap()
        .property_mut("prop")
        .unwrap();
    prop.set_value("new-value\0");

    // Verify the modification
    let child = (&tree.root)
        .children()
        .find(|c| c.name() == "child")
        .unwrap();
    assert_eq!(child.property("prop").unwrap().as_str(), Ok("new-value"));

    // Remove the property
    let child = tree.root.child_mut("child").unwrap();
    let removed_prop = child.remove_property("prop");
    assert!(removed_prop.is_some());
    assert_eq!((&*child).properties().count(), 0);

    // Remove the child
    let removed_child = tree.root.remove_child("child");
    assert!(removed_child.is_some());
    assert_eq!((&tree.root).children().count(), 0);
}

#[test]
fn find_node_mut() {
    let mut tree = DeviceTree::new();
    tree.root.add_child(
        DeviceTreeNode::builder("child-a")
            .child(DeviceTreeNode::builder("child-a-a").build())
            .build(),
    );
    tree.root
        .add_child(DeviceTreeNode::builder("child-b").build());

    // Find a nested child and modify it
    let child_a_a = tree.find_node_mut("/child-a/child-a-a").unwrap();
    child_a_a.add_property(DeviceTreeProperty::new("prop", "value\0"));

    // Verify the modification
    let child_a = (&tree.root)
        .children()
        .find(|c| c.name() == "child-a")
        .unwrap();
    let child_a_a = child_a
        .children()
        .find(|c| c.name() == "child-a-a")
        .unwrap();
    assert_eq!(child_a_a.property("prop").unwrap().as_str(), Ok("value"));

    // Find a non-existent node
    assert!(tree.find_node_mut("/child-a/child-c").is_none());
}

#[test]
fn device_tree_format() {
    let mut tree = DeviceTree::new();
    tree.root.add_child(
        DeviceTreeNode::builder("child-a")
            .child(DeviceTreeNode::builder("child-a-a").build())
            .build(),
    );
    tree.root
        .add_child(DeviceTreeNode::builder("child-b").build());

    let fds = tree.to_string();

    assert_eq!(
        fds,
        r#"/dts-v1/;

/ {
    child-a {
        child-a-a {
        };
    };

    child-b {
    };
};
"#
    );
}