unsaved_changes library

Detects unsaved changes on editable Flutter surfaces by diffing live state against a captured baseline, and reports what changed.

Classes

BaselineSource<T extends Object>

Where a tracker learns that the saved state it should compare against has been replaced — typically the provider or bloc holding the server's copy.

ChangeDetector<C, K extends Object>

Captures a baseline from C and reports how the live state differs.

ChangeSet<K extends Object>

An immutable read-model over the changes a tracker currently reports.

ChangeTracker<C, K extends Object>

Reports whether an editable surface still matches the state it was loaded with, and what differs.

ChangeTrackerObserver

Observes a tracker's lifecycle — for logging, breadcrumbs, or tests.

CollectionDetector<C, K extends Object, T>

Reports items added to, removed from, or edited inside a keyed collection.

DetectorSession<C, K extends Object>

A baseline captured by a ChangeDetector, able to diff against itself.

Facet<T, K extends Object>

One comparable aspect of a value, and the change kind it reports.

FieldGroup<C, K extends Object>

A set of fields that report one change kind between them.

FieldGroupDetector<C, K extends Object>

Reports a change per FieldGroup whose fields no longer match the baseline.

ItemSnapshot

What a keyed collection captured for one item.

MembershipDetector<C, K extends Object>

Reports keys entering or leaving a set — "which items has the user staged a resolution for", "which rows are selected".

PayloadDigest

The baseline for a PayloadDigestDetector: a canonical payload string, or a marker saying the payload cannot be diffed.

PayloadDigestDetector<C, K extends Object>

A safety net: digests the whole request payload and reports a change when it moves at all.

SnapshotChangeDetector<S, C, K extends Object>

A ChangeDetector that captures a value of type S and compares against it — the shape almost every detector wants.

StreamSignal

Adapts a Stream to a Listenable, so stream-based state (a bloc) can drive anything that expects a listenable.

TrackedChange<K extends Object>

A single difference between the captured baseline and the live state.

TrackerOptions

Tuning for a tracker.

ValueStreamDetector<C, S, K extends Object>

Compares facets of a single value read from C — a bloc state, a view model, a controller — and subscribes to the stream that publishes it.

Enums

CommonChangeKind

A ready-made change-kind enum for surfaces that do not need a bespoke one.

DetectorRole

How a tracker treats the changes a detector reports.

MembershipDelta

Which side of a membership change to report.

Functions

defaultEquals(Object? a, Object? b) → bool

Compares two captured values, descending into lists, maps, and sets.

nullableStringEquals(Object? a, Object? b) → bool

Treats null and the empty string as the same value.

streamBaseline<T extends Object>({required T? read(), required Stream<Object?> stream, Object? revisionOf(T value)?}) → BaselineSource<T>

Builds a BaselineSource from stream-based state — a bloc, a ValueStream, anything that republishes the saved copy.