Struct StampTransition 

pub struct StampTransition {
    pub previous: Option<VersionStamp>,
    pub current: VersionStamp,
}

What stamping observed. Returned so the daemon can act on an upgrade instead of silently erasing the evidence of one.

Fields

previous: Option<VersionStamp>

The stamp found on disk, if any. None on a fresh install — or when the file was unreadable, which is deliberately not distinguished here: both mean “no usable predecessor”, and doctor reports an unparseable stamp separately.

current: VersionStamp

What was written.

Implementations

impl StampTransition

pub fn upgraded(&self) -> bool

The package version changed since state was last written.

pub fn schema_from_the_future(&self) -> bool

On-disk state uses a schema generation NEWER than this binary understands — i.e. a downgrade.

This is the case STATE_SCHEMA_VERSION’s own contract calls out (“older than this should refuse rather than corrupt”) and that nothing acted on. A user reverting to an older CAR would silently operate on state written to a layout it does not know.

Trait Implementations

impl Clone for StampTransition

fn clone(&self) -> StampTransition

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for StampTransition

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

Formats the value using the given formatter.