Enum MigrationError 

pub enum MigrationError {
    NewerThanCurrent {
        on_disk: u32,
        current: u32,
    },
    NoStepFor(u32),
    Step {
        from: u32,
        message: String,
    },
    Deserialize(Error),
}

Errors surfaced by Migrator::run.

Variants

NewerThanCurrent

The on-disk version number exceeds T::CURRENT_VERSION; the file was written by a newer build and cannot be read safely.

Fields

on_disk: u32

current: u32

NoStepFor(u32)

The chain is missing a step for the encountered version, making it impossible to reach T::CURRENT_VERSION.

Step

A migration step closure returned Err(message).

Fields

from: u32

message: String

Deserialize(Error)

The migrated toml::Value did not deserialize as T.

Trait Implementations

impl Debug for MigrationError

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for MigrationError

fn fmt(&self, __formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Error for MigrationError

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.