fluent_result changelog

9.0.0 #

Breaking #

The core is now a Dart 3 sealed Result<T> with Ok<T> (non-null value) / Err<T>. ResultOf<T> is removed; value-free success is Result<void>.
Ok.value is non-null T (was ResultOf<T>.value : T?). Read it via pattern matching / valueOrNull / valueOr.
Single-error model: List<ResultError>, errors (plural), add/addAll, contains<T>/get<T> are removed. error (singular) and errorMessage remain.
fold is now value-returning (R fold<R>(onOk, onErr)); the 8.x void fold({onFail, onSuccess}) is gone. match is its named-parameter form.
A ResultMatcher build now returns a ResultError (was a ResultOf<dynamic>); the typed Err<T> is wrapped at the try* call site.
A thrown Error not claimed by a matcher now rethrows from try*/guard (reaching the Zone / crash reporter) instead of becoming a silent fail.
SDK floor raised to >=3.0.0.

Removed #

The 8.5 deprecated exceptionHandler, exceptionHandlerMatchers, logSuccessResult.
asResult (extension on Object), ResultException, the vestigial ResultConfig() factory.
The collection dependency — the package now has zero runtime dependencies.

Added #

Ok/Err sealed variants with exhaustive switch; value-based, symmetric ==/hashCode.
ResultError.code / cause / stackTrace; runtimeType in equality.
Value-returning fold + match; Err.cast<R>; combinators map/flatMap/flatMapAsync/recover/mapError/valueOr/getOrElse.
Error-rethrow policy with a matcher escape hatch (claim an Error type to convert it to Err).

Migration #

ResultOf<T> → Result<T>; result.value! → pattern matching or valueOrNull/valueOr.
Move any exceptionHandler reporting to onException; replace exceptionHandlerMatchers maps with matchers.
For Error-derived third-party exceptions (e.g. DioError extends Error), add a ResultMatcher((e) => e is Error, ...) or they will rethrow.

8.5.0 #

[Add] Global observability seam ResultConfig.onException (no-op by default) — the single place to wire crash reporting (e.g. Sentry). Unexpected caught exceptions are reported exactly once.
[Add] ResultMatcher + ResultConfig.matchers: ordered, subtype-aware error classification with an expected flag (expected errors are never reported).
[Add] ResultConfig.onSuccess, failBuilder, and reset() (call in test tearDown to avoid global-config leakage).
[Add] onErrorWithStack parameter on trySync/tryAsync.
[Add] ResultOf.guard/guardAsync to wrap a plain value-returning body.
[Add] Combinators on ResultOf<T>: flatMap, flatMapAsync, match, valueOr, getOrElse, recover, mapError.
[Change] failIf/okIf route through failBuilder — validation failures are never reported.
[Change] fail/failWith return ResultOf<T> (was ResultOf<T?>) — covariant, non-breaking.
[Change] Caught and successful results are no longer logged by default; the default exceptionHandlerMatchers is now empty.
[Change] SDK lower bound raised to >=2.14.0.
[Deprecate] exceptionHandler, exceptionHandlerMatchers, logSuccessResult — still honored, but prefer onException + matchers + onSuccess.
[Remove] logger and quiver dependencies.
[Docs] add a runnable example/, fill the public API dartdoc, and add pub.dev metadata (topics, repository, issue_tracker, corrected description).

Migration

If your ResultConfig.exceptionHandler reported errors itself, move that reporting into ResultConfig.onException to avoid double-reporting.
failIf/okIf now route through ResultConfig.failBuilder instead of exceptionHandler; if you customized exceptionHandler to shape their output, set failBuilder instead.
For Error-derived third-party exceptions (e.g. DioError extends Error), match with (e) => e is Error — the e is Exception catch-all does not match them.

8.4.1 #

[Fix] Result.hashCode is now stable and contract-correct, so equal Results share a hash code and work as Set/Map keys
[Fix] ResultOf.map() no longer drops all but the first error when mapping a multi-error fail result
[Fix] foldWithValue/map throw a clear StateError instead of an opaque TypeError when a non-nullable success value is null
[Docs] correct README exceptionHandlerMatchers matcher signature, nullable ResultOf.value, and Result.failWith usage

8.4.0 #

[Fix] can pass null in successWith(null)

8.3.0 #

add onFinally method to ResultOf and Result
update logger dependency to ^2.2.0

8.2.0 #

update logger dependency

8.1.0 #

downgrade collection: ^1.17.1

8.0.0 #

[Fix] logging stack trace.
[Update] dependencies.

7.3.0 #

[Add] Logger.

7.2.0 #

[Add] exception handler matchers.

7.1.1 #

[Add] onError in trySync/tryAsync for error handler customization.

7.1.0 #

[Add] logSuccessResult into ResultConfig
[Change] errorMessage now is non-nullable, by default is empty string.

7.0.0 #

[Add] ResultConfig to customize exceptionHandler
[Fix] tries

6.0.0 #

[Add] success, successWith, fail methods
[Add] trySync, tryAsync methods
[Change] toResult into map

5.0.0 #

Breaking changes

ResultError has not const constructor anymore.

Updates

Use withError and withErrors instead of fail and fails respectively.
[Add] folding onFail and onSuccess with fold(onFail, onSuccess).
[Add] mapping any object to ResultOf<T> with toResult().
[Add] failIf(condition, reason) and okIf(condition, failReason).

4.3.0 #

[Fix] contains<T>()
[Add] getting specific error from collection by get<T>

4.2.0 #

[Fix] contains<T>()

4.1.0 #

[Add] errors collection

4.0.1 #

[Migrate] to null-safety

4.0.0 #

[Update] dependencies for migration to null-safety

3.0.2 #

Add withErrorMessage(String) method to ResultOf
Add withException(Exception) method to ResultOf

3.0.1 #

[Add] withErrorMessage(String) method to Result
[Add] withException(Exception) method to Result

3.0.0+1 #

Correct README.md

3.0.0 #

[Add] ResultError object that describes a error and allows the errors to be typed.

2.0.0+1 #