1use core::fmt::Display;
 2
 3#[derive(Debug, PartialEq, Eq)]
 4pub enum TieredSmtProofError {
 5    EntriesEmpty,
 6    PathTooLong,
 7    NotATierPath(u8),
 8    MultipleEntriesOutsideLastTier,
 9    EmptyValueNotAllowed,
10    UnmatchingPrefixes(u64, u64),
11}
12
13impl Display for TieredSmtProofError {
14    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
15        match self {
16            TieredSmtProofError::EntriesEmpty => {
17                write!(f, "Missing entries for tiered sparse merkle tree proof")
18            }
19            TieredSmtProofError::PathTooLong => {
20                write!(
21                    f,
22                    "Path longer than maximum depth of 64 for tiered sparse merkle tree proof"
23                )
24            }
25            TieredSmtProofError::NotATierPath(got) => {
26                write!(
27                    f,
28                    "Path length does not correspond to a tier. Got {} Expected one of 16,32,48,64",
29                    got
30                )
31            }
32            TieredSmtProofError::MultipleEntriesOutsideLastTier => {
33                write!(f, "Multiple entries are only allowed for the last tier (depth 64)")
34            }
35            TieredSmtProofError::EmptyValueNotAllowed => {
36                write!(
37                    f,
38                    "The empty value [0,0,0,0] is not allowed inside a tiered sparse merkle tree"
39                )
40            }
41            TieredSmtProofError::UnmatchingPrefixes(first, second) => {
42                write!(f, "Not all leaves have the same prefix. First {} second {}", first, second)
43            }
44        }
45    }
46}
47
48#[cfg(feature = "std")]
49impl std::error::Error for TieredSmtProofError {}