prefix_trie/
fmt.rs

1//! Debug formatting for PrefixMap.
2//!
3//! The output hides the internal TreeBitMap structure and shows the logical prefix trie,
4//! matching the style of PrefixMap's debug output.
5
6use std::fmt::{Debug, Formatter, Result};
7
8use crate::{Prefix, PrefixMap};
9
10impl<P: Prefix + Debug, T: Debug> Debug for PrefixMap<P, T> {
11    fn fmt(&self, f: &mut Formatter<'_>) -> Result {
12        let entries: Vec<(P, &T)> = self.iter().collect();
13        DebugSubtree { entries: &entries }.fmt(f)
14    }
15}
16
17#[cfg(feature = "rkyv")]
18impl<P, T> Debug for crate::rkyv::ArchivedPrefixMap<P, T>
19where
20    P: Prefix + Debug,
21    T: rkyv::Archive,
22    T::Archived: Debug,
23{
24    fn fmt(&self, f: &mut Formatter<'_>) -> Result {
25        let entries: Vec<(P, &T::Archived)> = self.iter().collect();
26        DebugSubtree { entries: &entries }.fmt(f)
27    }
28}
29
30struct DebugSubtree<'a, P, T> {
31    entries: &'a [(P, &'a T)],
32}
33
34struct DebugExtendedNode<'a, P, T> {
35    value: &'a T,
36    children: DebugSubtree<'a, P, T>,
37}
38
39impl<P: Prefix + Debug, T: Debug> Debug for DebugExtendedNode<'_, P, T> {
40    fn fmt(&self, f: &mut Formatter<'_>) -> Result {
41        let mut d = f.debug_struct("");
42        d.field("value", self.value);
43        if !self.children.entries.is_empty() {
44            d.field("children", &self.children);
45        }
46        d.finish()
47    }
48}
49
50impl<P: Prefix + Debug, T: Debug> Debug for DebugSubtree<'_, P, T> {
51    fn fmt(&self, f: &mut Formatter<'_>) -> Result {
52        let mut dm = f.debug_map();
53        let mut entries = self.entries;
54
55        while let Some(((prefix, value), rest)) = entries.split_first() {
56            let child_count = rest.iter().take_while(|(p, _)| prefix.contains(p)).count();
57            let (children, remaining) = rest.split_at(child_count);
58            entries = remaining;
59
60            dm.entry(
61                prefix,
62                &DebugExtendedNode {
63                    value: *value,
64                    children: DebugSubtree { entries: children },
65                },
66            );
67        }
68
69        dm.finish()
70    }
71}
prefix_trie/fmt.rs

prefix_trie/
fmt.rs
