Enum MigrationError 

#[non_exhaustive]
pub enum MigrationError {
    MissingAttribute {
        name: String,
    },
    WrongType {
        name: String,
        expected: &'static str,
    },
    OutOfRange {
        name: String,
    },
    Custom {
        reason: String,
    },
}

Structured error returned by a Migration::rewrite function.

Migrations are fallible: a required input attribute may be missing, or a coerced value may not fit a narrower type. The error carries enough context for the decoder to surface a Diagnostic pinned to the offending op.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

MissingAttribute

A required attribute was missing from the input map.

Fields

name: String

Name of the missing attribute.

WrongType

An attribute carried the wrong type for the migration.

Fields

name: String

Name of the attribute.

expected: &'static str

The expected type, as a human-readable tag.

OutOfRange

A coerced numeric value did not fit the narrower target type.

Fields

name: String

Name of the attribute that overflowed.

Custom

The migration rejected the input for any other reason.

Fields

reason: String

Human-readable failure reason.

Trait Implementations

impl Clone for MigrationError

fn clone(&self) -> MigrationError

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

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, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for MigrationError

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.

impl PartialEq for MigrationError

fn eq(&self, other: &MigrationError) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for MigrationError