refactor(wyatt_type_utils)!: upgrade Result to prepare migration to sealed classes

This commit is contained in:
Hugo Pointcheval 2024-02-18 22:48:20 +01:00
parent 7785f3f117
commit 41382aad2f
Signed by: hugo
GPG Key ID: 3AAC487E131E00BC
12 changed files with 452 additions and 432 deletions

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@ -1,26 +1,21 @@
// // Copyright (C) 2022 WYATT GROUP // Copyright (C) 2024 WYATT GROUP
// // Please see the AUTHORS file for details. // Please see the AUTHORS file for details.
// // //
// // This program is free software: you can redistribute it and/or modify // This program is free software: you can redistribute it and/or modify
// // it under the terms of the GNU General Public License as published by // it under the terms of the GNU General Public License as published by
// // the Free Software Foundation, either version 3 of the License, or // the Free Software Foundation, either version 3 of the License, or
// // any later version. // any later version.
// // //
// // This program is distributed in the hope that it will be useful, // This program is distributed in the hope that it will be useful,
// // but WITHOUT ANY WARRANTY; without even the implied warranty of // but WITHOUT ANY WARRANTY; without even the implied warranty of
// // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// // GNU General Public License for more details. // GNU General Public License for more details.
// // //
// // You should have received a copy of the GNU General Public License // You should have received a copy of the GNU General Public License
// // along with this program. If not, see <https://www.gnu.org/licenses/>. // along with this program. If not, see <https://www.gnu.org/licenses/>.
// // ignore_for_file: avoid_positional_boolean_parameters
import 'dart:async'; import 'dart:async';
part 'future_result.dart';
part 'future_or_result.dart';
part 'result.dart';
part 'option.dart'; part 'option.dart';
mixin _Left<LeftType, RightType> on _EitherBase<LeftType, RightType> {} mixin _Left<LeftType, RightType> on _EitherBase<LeftType, RightType> {}
@ -35,7 +30,9 @@ class _EitherBaseException implements Exception {
String toString() => '_EitherException: $message'; String toString() => '_EitherException: $message';
} }
@Deprecated('Use Dart pattern matching instead')
abstract class _EitherBase<LeftType, RightType> { abstract class _EitherBase<LeftType, RightType> {
@Deprecated('Use Dart pattern matching instead')
const _EitherBase(); const _EitherBase();
bool get _isLeft => this is _Left<LeftType, RightType>; bool get _isLeft => this is _Left<LeftType, RightType>;
@ -56,20 +53,20 @@ abstract class _EitherBase<LeftType, RightType> {
if (U == LeftType) { if (U == LeftType) {
return _fold<LeftType>( return _fold<LeftType>(
(value) => value, (value) => value,
(right) => throw const ResultException( (right) => throw Exception(
'Illegal use. You should check left value before calling', 'Illegal use. You should check left value before calling',
), ),
) as U; ) as U;
} }
if (U == RightType) { if (U == RightType) {
return _fold<RightType>( return _fold<RightType>(
(left) => throw const ResultException( (left) => throw Exception(
'Illegal use. You should check right value before calling', 'Illegal use. You should check right value before calling',
), ),
(value) => value, (value) => value,
) as U; ) as U;
} }
throw ResultException( throw Exception(
'Illegal use. You should use $LeftType or $RightType type', 'Illegal use. You should use $LeftType or $RightType type',
); );
} }
@ -78,20 +75,20 @@ abstract class _EitherBase<LeftType, RightType> {
if (U == LeftType) { if (U == LeftType) {
return _foldAsync<LeftType>( return _foldAsync<LeftType>(
Future.value, Future.value,
(right) => throw const ResultException( (right) => throw Exception(
'Illegal use. You should check left value before calling', 'Illegal use. You should check left value before calling',
), ),
) as Future<U>; ) as Future<U>;
} }
if (U == RightType) { if (U == RightType) {
return _foldAsync<RightType>( return _foldAsync<RightType>(
(left) => throw const ResultException( (left) => throw Exception(
'Illegal use. You should check right value before calling', 'Illegal use. You should check right value before calling',
), ),
Future.value, Future.value,
) as Future<U>; ) as Future<U>;
} }
throw ResultException( throw Exception(
'Illegal use. You should use $LeftType or $RightType type', 'Illegal use. You should use $LeftType or $RightType type',
); );
} }

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@ -1,4 +1,4 @@
// Copyright (C) 2022 WYATT GROUP // Copyright (C) 2024 WYATT GROUP
// Please see the AUTHORS file for details. // Please see the AUTHORS file for details.
// //
// This program is free software: you can redistribute it and/or modify // This program is free software: you can redistribute it and/or modify
@ -41,8 +41,10 @@ class OptionException extends _EitherBaseException {
/// if value not present) and ifPresent() (execute a block of code if the /// if value not present) and ifPresent() (execute a block of code if the
/// value is present). /// value is present).
/// {@endtemplate} /// {@endtemplate}
@Deprecated('Use Dart pattern matching instead')
abstract class Option<T> extends _EitherBase<T, void> { abstract class Option<T> extends _EitherBase<T, void> {
/// {@macro option} /// {@macro option}
@Deprecated('Use Dart pattern matching instead')
const Option._(); const Option._();
/// Represents the left side of [Option] class. /// Represents the left side of [Option] class.

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@ -1,325 +0,0 @@
// Copyright (C) 2022 WYATT GROUP
// Please see the AUTHORS file for details.
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <https://www.gnu.org/licenses/>.
// ignore_for_file: avoid_positional_boolean_parameters
part of 'either_base.dart';
/// {@template result_exception}
/// [ResultException] is sometimes threw by [Result] objects.
///
/// ```dart
/// throw ResultException('Emergency failure!');
/// ```
/// {@endtemplate}
class ResultException extends _EitherBaseException {
/// {@macro result_exception}
const ResultException(super.message);
@override
String toString() => 'ResultException: $message';
}
/// {@template result}
/// [Result] type is coming from functional languages where exceptions are
/// (rightfully) considered a side-effect, and therefore not appropriate to
/// pass domain errors. Mind the difference between different kinds of errors:
/// Some of them belong to domain, others don't.
///
/// *E.g. null reference exception or index out of bounds
/// are not related to domain - they rather indicate a defect.*
///
/// Either is defined as a generic type with two branches
/// - success with [T]
/// - failure with [E]
///
/// It can appear in two forms, where
/// it contains an object of [Ok], or where it contains an object
/// of [Err]. It cannot appear in both states at once, or in none of them.
/// Therefore, if one possesses an [Result] instance, it either contains a
/// successfully produced result, or contains an error object.
/// {@endtemplate}
abstract class Result<T, E> extends _EitherBase<T, E> {
/// {@macro result}
const Result._();
/// Represents the left side of [Result] class.
bool get isOk => _isLeft;
/// Represents the right side of [Result] class.
bool get isErr => _isRight;
/// Get nullable [Ok] value, and discarding the error, if any.
T? get ok => _left;
/// Get nullable [Err] value, and discarding the success value, if any.
E? get err => _right;
/// Get [U] value, may throw an exception.
U unwrap<U>() => _unwrap<U>();
/// Get **async** [U] value, may throw an exception.
Future<U> unwrapAsync<U>() => _unwrapAsync<U>();
/// Fold [Ok] and [Err] into the value of one type
U fold<U>(
U Function(T value) valueTransformer,
U Function(E error) errorTransformer,
) =>
_fold(
(left) => valueTransformer(left),
(right) => errorTransformer(right),
);
/// Fold [Ok] and [Err] **asynchronously** into the value of one type
Future<U> foldAsync<U>(
Future<U> Function(T value) valueTransformer,
Future<U> Function(E error) errorTransformer,
) =>
_foldAsync(
(left) => valueTransformer(left),
(right) => errorTransformer(right),
);
/// Swap [Ok] and [Err]
Result<E, T> swap() => fold(Err.new, Ok.new);
/// Returns [res] if the [Result] is [Ok], otherwise returns
/// the [Err] value of this.
Result<U, E> and<U>(Result<U, E> res) => _and<U>(res) as Result<U, E>;
/// Returns [res] if the [Result] is [Err], otherwise returns
/// the [Ok] value of this.
Result<T, F> or<F>(Result<T, F> res) => _or<F>(res) as Result<T, F>;
/// Returns true if the result is an [Ok] or [Err] value containing
/// the given value/error.
bool contains<U>(U x) => _contains(x);
/// Returns the contained [Ok] value. Throw [ResultException] on [Err] with
/// its content.
T expect(String msg) => _expect(msg);
/// Returns the contained [Err] value. Throw [ResultException] on [Ok] with
/// its content.
E expectErr(String msg) => _expectErr(msg);
/// Maps a [Result<T, E>] to [Result<U, E>] by applying a function to a
/// contained [Ok] value, leaving an [Err] value untouched.
Result<U, E> map<U>(U Function(T value) mapper) =>
_map(mapper) as Result<U, E>;
/// Maps a [Result<T, E>] to [Result<U, E>] by applying an **async** function
/// to a contained [Ok] value, leaving an [Err] value untouched.
Future<Result<U, E>> mapAsync<U>(Future<U> Function(T value) mapper) =>
_mapAsync(mapper) as Future<Result<U, E>>;
/// Maps a [Result<T, E>] to [Result<T, F>] by applying a function to a
/// contained [Err] value, leaving an [Ok] value untouched.
Result<T, F> mapErr<F>(F Function(E error) mapper) =>
_mapErr(mapper) as Result<T, F>;
/// Maps a [Result<T, E>] to [Result<U, E>] by applying an **async** function
/// to a contained [Err] value, leaving an [Ok] value untouched.
Future<Result<T, F>> mapErrAsync<F>(Future<F> Function(E error) mapper) =>
_mapErrAsync(mapper) as Future<Result<T, F>>;
/// Transforms a [Result<T, E>] to [Result<U, F>] by applying functions to
/// contained [Ok] and [Err] values.
Result<U, F> either<U, F>(
U Function(T value) valueTransformer,
F Function(E error) errorTransformer,
) =>
_either<U, F>(valueTransformer, errorTransformer) as Result<U, F>;
/// Transforms a [Result<T, E>] to [Result<U, F>] by applying **async**
/// functions to contained [Ok] and [Err] values.
Future<Result<U, F>> eitherAsync<U, F>(
Future<U> Function(T value) valueTransformer,
Future<F> Function(E error) errorTransformer,
) =>
_eitherAsync<U, F>(valueTransformer, errorTransformer)
as Future<Result<U, F>>;
/// Constructs a new [Result] from a function that might throw
static Result<T, E> tryCatch<T, E, Error extends Object>(
T Function() tryFn,
E Function(Error error) onError,
) {
try {
return Ok(tryFn());
} on Error catch (e) {
return Err(onError(e));
}
}
/// Constructs a new [Result] from an **async** function that might throw
static Future<Result<T, E>> tryCatchAsync<T, E, Error extends Object>(
Future<T> Function() tryFn,
E Function(Error error) onError,
) async {
try {
return Ok(await tryFn());
} on Error catch (e) {
return Err(onError(e));
}
}
/// If the condition is satify then return [value] in
/// [Ok] else [error] in [Err]
static Result<T, E> conditional<T, E>(
bool test,
T value,
E error,
) =>
test ? Ok(value) : Err(error);
/// If the condition is satify then return *command* [value]
/// in [Ok] else [error] in [Err]
static Result<T, E> conditionalLazy<T, E>(
bool test,
T Function() value,
E Function() error,
) =>
test ? Ok(value()) : Err(error());
}
/// {@template ok}
/// Contains the success value of a [Result]
///
/// {@macro result}
/// {@endtemplate}
class Ok<T, E> extends Result<T, E> with _Left<T, E> {
/// {@macro ok}
const Ok(this.value) : super._();
final T value;
@override
U _fold<U>(U Function(T left) fnL, U Function(E right) fnR) => fnL(value);
@override
Future<U> _foldAsync<U>(
Future<U> Function(T left) fnL,
Future<U> Function(E right) fnR,
) =>
fnL(value);
@override
Result<U, E> _and<U>(_EitherBase<U, E> res) => res as Result<U, E>;
@override
Result<T, F> _or<F>(_EitherBase<T, F> res) => this as Result<T, F>;
@override
bool _contains<U>(U x) => value == x;
@override
T _expect(String msg) => value;
@override
E _expectErr(String msg) => throw ResultException('$msg: $value');
@override
Result<U, E> _map<U>(U Function(T value) mapper) => Ok(mapper(value));
@override
Future<Result<U, E>> _mapAsync<U>(Future<U> Function(T value) mapper) =>
mapper(value).then(Ok.new);
@override
Result<T, F> _mapErr<F>(F Function(E error) mapper) => Ok(value);
@override
Future<Result<T, F>> _mapErrAsync<F>(Future<F> Function(E error) mapper) =>
Future.value(Ok(value));
@override
Result<U, F> _either<U, F>(
U Function(T value) fnL,
F Function(E error) fnR,
) =>
Ok(fnL(value));
@override
Future<Result<U, F>> _eitherAsync<U, F>(
Future<U> Function(T value) fnL,
Future<F> Function(E error) fnR,
) =>
fnL(value).then(Ok.new);
}
/// {@template err}
/// Contains the error value of a [Result]
///
/// {@macro result}
/// {@endtemplate}
class Err<T, E> extends Result<T, E> with _Right<T, E> {
/// {@macro err}
const Err(this.error) : super._();
final E error;
@override
U _fold<U>(U Function(T left) fnL, U Function(E right) fnR) => fnR(error);
@override
Future<U> _foldAsync<U>(
Future<U> Function(T left) fnL,
Future<U> Function(E right) fnR,
) =>
fnR(error);
@override
Result<U, E> _and<U>(_EitherBase<U, E> res) => this as Result<U, E>;
@override
Result<T, F> _or<F>(_EitherBase<T, F> res) => res as Result<T, F>;
@override
bool _contains<U>(U x) => error == x;
@override
T _expect(String msg) => throw ResultException('$msg: $error');
@override
E _expectErr(String msg) => error;
@override
Result<U, E> _map<U>(U Function(T value) mapper) => Err(error);
@override
Future<Result<U, E>> _mapAsync<U>(Future<U> Function(T value) mapper) =>
Future.value(Err(error));
@override
Result<T, F> _mapErr<F>(F Function(E error) mapper) => Err(mapper(error));
@override
Future<Result<T, F>> _mapErrAsync<F>(Future<F> Function(E error) mapper) =>
mapper(error).then(Err.new);
@override
Result<U, F> _either<U, F>(
U Function(T value) fnL,
F Function(E error) fnR,
) =>
Err(fnR(error));
@override
Future<Result<U, F>> _eitherAsync<U, F>(
Future<U> Function(T value) fnL,
Future<F> Function(E error) fnR,
) =>
fnR(error).then(Err.new);
}

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@ -37,13 +37,10 @@ extension IterableIntExtension on Iterable<int>? {
switch (to) { switch (to) {
case Encoding.utf8: case Encoding.utf8:
str = utf8.decode(this?.toList() ?? []); str = utf8.decode(this?.toList() ?? []);
break;
case Encoding.utf16: case Encoding.utf16:
str = String.fromCharCodes(this ?? []); str = String.fromCharCodes(this ?? []);
break;
case Encoding.base64: case Encoding.base64:
str = base64.encode(this?.toList() ?? []); str = base64.encode(this?.toList() ?? []);
break;
case Encoding.base16: case Encoding.base16:
str = List.generate( str = List.generate(
(this ?? []).length, (this ?? []).length,

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@ -33,13 +33,10 @@ extension StringExtension on String? {
switch (from) { switch (from) {
case Encoding.utf8: case Encoding.utf8:
bytes = utf8.encode(this ?? '').toTypedList(); bytes = utf8.encode(this ?? '').toTypedList();
break;
case Encoding.utf16: case Encoding.utf16:
bytes = (this ?? '').runes.toList().toTypedList(); bytes = (this ?? '').runes.toList().toTypedList();
break;
case Encoding.base64: case Encoding.base64:
bytes = base64.decode(this ?? ''); bytes = base64.decode(this ?? '');
break;
case Encoding.base16: case Encoding.base16:
assert( assert(
(this ?? '').length.isEven, (this ?? '').length.isEven,

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@ -21,8 +21,10 @@ extension PairExtension<T> on Pair<T, T> {
/// {@template pair} /// {@template pair}
/// [Pair] is a simple object which contains pair of two values. /// [Pair] is a simple object which contains pair of two values.
/// {@endtemplate} /// {@endtemplate}
@Deprecated('Use Dart built-in record type instead')
class Pair<L, R> { class Pair<L, R> {
/// {@macro pair} /// {@macro pair}
@Deprecated('Use Dart built-in record type instead')
const Pair(this.left, this.right); const Pair(this.left, this.right);
final L? left; final L? left;
final R? right; final R? right;

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@ -1,4 +1,4 @@
// Copyright (C) 2022 WYATT GROUP // Copyright (C) 2024 WYATT GROUP
// Please see the AUTHORS file for details. // Please see the AUTHORS file for details.
// //
// This program is free software: you can redistribute it and/or modify // This program is free software: you can redistribute it and/or modify
@ -14,7 +14,9 @@
// You should have received a copy of the GNU General Public License // You should have received a copy of the GNU General Public License
// along with this program. If not, see <https://www.gnu.org/licenses/>. // along with this program. If not, see <https://www.gnu.org/licenses/>.
part of 'either_base.dart'; import 'dart:async';
import 'package:wyatt_type_utils/src/result/result.dart';
extension FutureOrResultExtension<T, E> on FutureOr<Result<T, E>> { extension FutureOrResultExtension<T, E> on FutureOr<Result<T, E>> {
/// Represents the left side of [Result] class. /// Represents the left side of [Result] class.
@ -72,13 +74,13 @@ extension FutureOrResultExtension<T, E> on FutureOr<Result<T, E>> {
Future<bool> contains<U>(U x) => Future<bool> contains<U>(U x) =>
Future.value(this).then((result) => result.contains(x)); Future.value(this).then((result) => result.contains(x));
/// Returns the contained [Ok] value. Throw [ResultException] on [Err] with /// Returns the contained [Ok] value. Throw [ResultException] on
/// its content. /// [Err] with its content.
Future<T> expect(String msg) => Future<T> expect(String msg) =>
Future.value(this).then((result) => result.expect(msg)); Future.value(this).then((result) => result.expect(msg));
/// Returns the contained [Err] value. Throw [ResultException] on [Ok] with /// Returns the contained [Err] value. Throw [ResultException] on
/// its content. /// [Ok] with its content.
Future<E> expectErr(String msg) => Future<E> expectErr(String msg) =>
Future.value(this).then((result) => result.expectErr(msg)); Future.value(this).then((result) => result.expectErr(msg));

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@ -1,4 +1,4 @@
// Copyright (C) 2022 WYATT GROUP // Copyright (C) 2024 WYATT GROUP
// Please see the AUTHORS file for details. // Please see the AUTHORS file for details.
// //
// This program is free software: you can redistribute it and/or modify // This program is free software: you can redistribute it and/or modify
@ -14,7 +14,7 @@
// You should have received a copy of the GNU General Public License // You should have received a copy of the GNU General Public License
// along with this program. If not, see <https://www.gnu.org/licenses/>. // along with this program. If not, see <https://www.gnu.org/licenses/>.
part of 'either_base.dart'; import 'package:wyatt_type_utils/src/result/result.dart';
extension FutureResultExtension<T, E> on Future<Result<T, E>> { extension FutureResultExtension<T, E> on Future<Result<T, E>> {
/// Represents the left side of [Result] class. /// Represents the left side of [Result] class.
@ -62,12 +62,12 @@ extension FutureResultExtension<T, E> on Future<Result<T, E>> {
/// the given value/error. /// the given value/error.
Future<bool> contains<U>(U x) => then((result) => result.contains(x)); Future<bool> contains<U>(U x) => then((result) => result.contains(x));
/// Returns the contained [Ok] value. Throw [ResultException] on [Err] with /// Returns the contained [Ok] value. Throw [ResultException] on
/// its content. /// [Err] with its content.
Future<T> expect(String msg) => then((result) => result.expect(msg)); Future<T> expect(String msg) => then((result) => result.expect(msg));
/// Returns the contained [Err] value. Throw [ResultException] on [Ok] with /// Returns the contained [Err] value. Throw [ResultException] on
/// its content. /// [Ok] with its content.
Future<E> expectErr(String msg) => then((result) => result.expectErr(msg)); Future<E> expectErr(String msg) => then((result) => result.expectErr(msg));
/// Maps a [Result<T, E>] to [Result<U, E>] by applying a function to a /// Maps a [Result<T, E>] to [Result<U, E>] by applying a function to a

View File

@ -0,0 +1,346 @@
// Copyright (C) 2024 WYATT GROUP
// Please see the AUTHORS file for details.
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <https://www.gnu.org/licenses/>.
// ignore_for_file: avoid_equals_and_hash_code_on_mutable_classes
import 'package:sealed_result/sealed_result.dart' as sealed;
export 'future_or_result.dart';
export 'future_result.dart';
class ResultException extends sealed.ResultException {
const ResultException(String super.message);
}
/// {@template result}
/// [Result] type is coming from functional languages where exceptions are
/// (rightfully) considered a side-effect, and therefore not appropriate to
/// pass domain errors. Mind the difference between different kinds of errors:
/// Some of them belong to domain, others don't.
///
/// *E.g. null reference exception or index out of bounds
/// are not related to domain - they rather indicate a defect.*
///
/// Either is defined as a generic type with two branches
/// - success with [Success]
/// - failure with [Failure]
///
/// It can appear in two forms, where
/// it contains an object of [Ok], or where it contains an object
/// of [Err]. It cannot appear in both states at once, or in none of them.
/// Therefore, if one possesses an [Result] instance, it either contains a
/// successfully produced result, or contains an error object.
/// {@endtemplate}
class Result<Success, Failure> {
/// {@macro result}
const Result._(this._result);
factory Result.ok(Success value) => Ok(value);
factory Result.err(Failure value) => Err(value);
factory Result.error(Failure value) => Err(value);
factory Result.success(Success value) => Ok(value);
factory Result.failure(Failure value) => Err(value);
final sealed.Result<Success, Failure> _result;
/// Represents the left side of [Result] class.
bool get isOk => _result.isOk;
/// Represents the right side of [Result] class.
bool get isErr => _result.isErr;
/// Get nullable [Ok] value, and discarding the error, if any.
Success? get ok => _result.ok;
/// Get nullable [Err] value, and discarding the success value, if any.
Failure? get err => _result.err;
/// Get [U] value, may throw an exception.
U unwrap<U>() {
if (U == Success) {
return fold<Success>(
(value) => value,
(right) => throw const ResultException(
'Illegal use. You should check left value before calling',
),
) as U;
}
if (U == Failure) {
return fold<Failure>(
(left) => throw const ResultException(
'Illegal use. You should check right value before calling',
),
(value) => value,
) as U;
}
throw ResultException(
'Illegal use. You should use $Success or $Failure type',
);
}
/// Get **async** [U] value, may throw an exception.
Future<U> unwrapAsync<U>() {
if (U == Success) {
return foldAsync<Success>(
Future.value,
(right) => throw const ResultException(
'Illegal use. You should check left value before calling',
),
) as Future<U>;
}
if (U == Failure) {
return foldAsync<Failure>(
(left) => throw const ResultException(
'Illegal use. You should check right value before calling',
),
Future.value,
) as Future<U>;
}
throw ResultException(
'Illegal use. You should use $Success or $Failure type',
);
}
/// Fold [Ok] and [Err] into the value of one type
U fold<U>(
U Function(Success value) valueTransformer,
U Function(Failure error) errorTransformer,
) =>
_result.fold(
(ok) => valueTransformer(ok),
(err) => errorTransformer(err),
);
/// Fold [Ok] and [Err] **asynchronously** into the value of one type
Future<U> foldAsync<U>(
Future<U> Function(Success value) valueTransformer,
Future<U> Function(Failure error) errorTransformer,
) =>
_result.foldAsync(
(ok) => valueTransformer(ok),
(err) => errorTransformer(err),
);
/// Swap [Ok] and [Err]
Result<Failure, Success> swap() => fold(
Err.new,
Ok.new,
);
/// Returns [res] if the [Result] is [Ok], otherwise returns
/// the [Err] value of this.
Result<U, Failure> and<U>(Result<U, Failure> res) => Result._(
_result.and(res._result),
);
/// Returns [res] if the [Result] is [Err], otherwise returns
/// the [Ok] value of this.
Result<Success, F> or<F>(Result<Success, F> res) => Result._(
_result.or(res._result),
);
/// Returns true if the result is an [Ok] or [Err] value containing
/// the given value/error.
bool contains<U>(U x) {
if (x is Success) {
return _result.contains(x);
} else if (x is Failure) {
return _result.containsErr(x);
} else {
throw ArgumentError('The value must be of type Success or Failure');
}
}
/// Returns the contained [Ok] value. Throw [ResultException] on [Err]
/// with its content.
Success expect(String msg) {
try {
return _result.expect(msg);
} on sealed.ResultException catch (e) {
throw ResultException(e.message.toString());
}
}
/// Returns the contained [Err] value. Throw [ResultException] on [Ok]
/// with its content.
Failure expectErr(String msg) {
try {
return _result.expectErr(msg);
} on sealed.ResultException catch (e) {
throw ResultException(e.message.toString());
}
}
/// Maps a [Result<Success, Failure>] to [Result<U, Failure>] by applying a
/// function to a contained [Ok] value, leaving an [Err] value untouched.
Result<U, Failure> map<U>(U Function(Success value) mapper) =>
Result._(_result.map(mapper));
/// Maps a [Result<Success, Failure>] to [Result<U, Failure>] by applying
/// an **async** function to a contained [Ok] value, leaving an [Err]
/// value untouched.
Future<Result<U, Failure>> mapAsync<U>(
Future<U> Function(Success value) mapper,
) async {
final result = await _result.mapAsync(mapper);
return Result._(result);
}
/// Maps a [Result<Success, Failure>] to [Result<Success, F>] by applying a
/// function to a contained [Err] value, leaving an [Ok] value untouched.
Result<Success, F> mapErr<F>(F Function(Failure error) mapper) =>
Result._(_result.mapErr(mapper));
/// Maps a [Result<Success, Failure>] to [Result<U, Failure>] by applying
/// an **async** function to a contained [Err] value, leaving an [Ok]
/// value untouched.
Future<Result<Success, F>> mapErrAsync<F>(
Future<F> Function(Failure error) mapper,
) async {
final result = await _result.mapErrAsync(mapper);
return Result._(result);
}
/// Transforms a [Result<Success, Failure>] to [Result<U, F>] by applying
/// functions to contained [Ok] and [Err] values.
Result<U, F> either<U, F>(
U Function(Success value) valueTransformer,
F Function(Failure error) errorTransformer,
) =>
Result._(
_result
.map(
valueTransformer,
)
.mapErr(
errorTransformer,
),
);
/// Transforms a [Result<Success, Failure>] to [Result<U, F>] by
/// applying **async** functions to contained [Ok] and [Err] values.
Future<Result<U, F>> eitherAsync<U, F>(
Future<U> Function(Success value) valueTransformer,
Future<F> Function(Failure error) errorTransformer,
) =>
_result
.mapAsync(
valueTransformer,
)
.mapErrAsync(
errorTransformer,
)
.then(Result._);
/// Constructs a new [Result] from a function that might throw
static Result<Success, Failure>
tryCatch<Success, Failure, Error extends Object>(
Success Function() tryFn,
Failure Function(Error error) onError,
) {
try {
return Ok(tryFn());
} on Error catch (e) {
return Err(onError(e));
}
}
/// Constructs a new [Result] from an **async** function that might throw
static Future<Result<Success, Failure>>
tryCatchAsync<Success, Failure, Error extends Object>(
Future<Success> Function() tryFn,
Failure Function(Error error) onError,
) async {
try {
return Ok(await tryFn());
} on Error catch (e) {
return Err(onError(e));
}
}
/// If the condition is satify then return [value] in
/// [Ok] else [error] in [Err]
static Result<Success, Failure> conditional<Success, Failure>(
Success value,
Failure error, {
required bool test,
}) =>
test ? Ok(value) : Err(error);
/// If the condition is satify then return *command* [value]
/// in [Ok] else [error] in [Err]
static Result<Success, Failure> conditionalLazy<Success, Failure>(
Success Function() value,
Failure Function() error,
bool Function() predicate,
) =>
predicate.call() ? Ok(value()) : Err(error());
@override
int get hashCode => _result.hashCode;
@override
bool operator ==(Object other) {
if (identical(this, other)) {
return true;
}
return other is Result<Success, Failure> && other._result == _result;
}
}
final class Ok<Success, Failure> extends Result<Success, Failure> {
Ok(this.ok) : super._(sealed.Ok(ok));
@override
final Success ok;
@override
bool get isErr => false;
@override
bool get isOk => true;
@override
Failure? get err => null;
@override
String toString() => switch (ok) {
null => 'Ok(null)',
Future() => 'Ok(${ok.runtimeType})',
_ => 'Ok($ok)',
};
}
final class Err<Success, Failure> extends Result<Success, Failure> {
Err(this.err) : super._(sealed.Err(err));
@override
final Failure err;
@override
bool get isErr => true;
@override
bool get isOk => false;
@override
Success? get ok => null;
@override
String toString() => switch (err) {
_ => 'Err($err)',
};
}

View File

@ -1,4 +1,4 @@
// Copyright (C) 2022 WYATT GROUP // Copyright (C) 2024 WYATT GROUP
// Please see the AUTHORS file for details. // Please see the AUTHORS file for details.
// //
// This program is free software: you can redistribute it and/or modify // This program is free software: you can redistribute it and/or modify
@ -17,3 +17,4 @@
export 'either/either_base.dart'; export 'either/either_base.dart';
export 'extensions/extensions.dart'; export 'extensions/extensions.dart';
export 'pair/pair.dart'; export 'pair/pair.dart';
export 'result/result.dart';

View File

@ -6,11 +6,14 @@ version: 0.0.5
publish_to: https://git.wyatt-studio.fr/api/packages/Wyatt-FOSS/pub publish_to: https://git.wyatt-studio.fr/api/packages/Wyatt-FOSS/pub
environment: environment:
sdk: ">=2.17.0 <3.0.0" sdk: "^3.0.0"
dependencies:
sealed_result: ^3.0.0
dev_dependencies: dev_dependencies:
test: ^1.22.0 test: ^1.22.0
wyatt_analysis: wyatt_analysis:
hosted: https://git.wyatt-studio.fr/api/packages/Wyatt-FOSS/pub hosted: https://git.wyatt-studio.fr/api/packages/Wyatt-FOSS/pub
version: ^2.5.0 version: ^2.6.1

View File

@ -21,85 +21,83 @@ void main() {
group('Result<T,E>', () { group('Result<T,E>', () {
test('`isOk` returns true on Ok value', () { test('`isOk` returns true on Ok value', () {
expect( expect(
const Ok<void, void>(null).isOk, Ok<void, void>(null).isOk,
true, true,
); );
expect( expect(
const Err<void, void>(null).isOk, Err<void, void>(null).isOk,
false, false,
); );
}); });
test('`isErr` returns true on Err value', () { test('`isErr` returns true on Err value', () {
expect( expect(
const Ok<void, void>(null).isErr, Ok<void, void>(null).isErr,
false, false,
); );
expect( expect(
const Err<void, void>(null).isErr, Err<void, void>(null).isErr,
true, true,
); );
}); });
test('`ok` returns value on Ok value', () { test('`ok` returns value on Ok value', () {
const Result<int, String> x = Ok(2); final Result<int, String> x = Ok(2);
expect(x.ok, 2); expect(x.ok, 2);
expect(x.err, null); expect(x.err, null);
}); });
test('`err` returns error on Err value', () { test('`err` returns error on Err value', () {
const Result<int, String> x = Err('error'); final Result<int, String> x = Err('error');
expect(x.ok, null); expect(x.ok, null);
expect(x.err, 'error'); expect(x.err, 'error');
}); });
test('unwrap() returns value on Ok value', () { test('unwrap() returns value on Ok value', () {
const Result<int, String> x = Ok(2); final Result<int, String> x = Ok(2);
expect(x.unwrap<int>(), 2); expect(x.unwrap<int>(), 2);
expect(() => x.unwrap<String>(), throwsA(isException)); expect(() => x.unwrap<String>(), throwsA(isException));
}); });
test('unwrap() returns error on Err value', () { test('unwrap() returns error on Err value', () {
const Result<int, String> x = Err('error'); final Result<int, String> x = Err('error');
expect(x.unwrap<String>(), 'error'); expect(x.unwrap<String>(), 'error');
expect(() => x.unwrap<int>(), throwsA(isException)); expect(() => x.unwrap<int>(), throwsA(isException));
}); });
test('unwrapAsync() returns value on Ok value', () async { test('unwrapAsync() returns value on Ok value', () async {
const Result<int, String> x = Ok(2); final Result<int, String> x = Ok(2);
expect(await x.unwrapAsync<int>(), 2); expect(await x.unwrapAsync<int>(), 2);
expect(() async => x.unwrapAsync<String>(), throwsA(isException)); expect(() async => x.unwrapAsync<String>(), throwsA(isException));
}); });
test('unwrapAsync() returns error on Err value', () async { test('unwrapAsync() returns error on Err value', () async {
const Result<int, String> x = Err('error'); final Result<int, String> x = Err('error');
expect(await x.unwrapAsync<String>(), 'error'); expect(await x.unwrapAsync<String>(), 'error');
expect(() async => x.unwrapAsync<int>(), throwsA(isException)); expect(() async => x.unwrapAsync<int>(), throwsA(isException));
}); });
test('fold() returns right value', () { test('fold() returns right value', () {
expect( expect(
const Ok<String, String>('') Ok<String, String>('').fold<bool>((left) => true, (right) => false),
.fold<bool>((left) => true, (right) => false),
true, true,
); );
expect( expect(
const Err<String, String>('') Err<String, String>('').fold<bool>((left) => true, (right) => false),
.fold<bool>((left) => true, (right) => false),
false, false,
); );
}); });
test('foldAsync() returns right value', () async { test('foldAsync() returns right value', () async {
expect( expect(
await const Ok<String, String>('').foldAsync<bool>( await Ok<String, String>('').foldAsync<bool>(
(left) => Future.value(true), (left) => Future.value(true),
(right) => Future.value(false), (right) => Future.value(false),
), ),
true, true,
); );
expect( expect(
await const Err<String, String>('').foldAsync<bool>( await Err<String, String>('').foldAsync<bool>(
(left) => Future.value(true), (left) => Future.value(true),
(right) => Future.value(false), (right) => Future.value(false),
), ),
@ -108,7 +106,7 @@ void main() {
}); });
test('swap() swaps values', () { test('swap() swaps values', () {
const Result<int, int> x = Ok(10); final Result<int, int> x = Ok(10);
expect(x.isOk, true); expect(x.isOk, true);
expect(x.isErr, false); expect(x.isErr, false);
expect(x.ok, 10); expect(x.ok, 10);
@ -122,24 +120,24 @@ void main() {
'and() returns res if the result is `Ok`, otherwise ' 'and() returns res if the result is `Ok`, otherwise '
'returns the `Err` value of this.', 'returns the `Err` value of this.',
() { () {
const Result<int, String> x1 = Ok(2); final Result<int, String> x1 = Ok(2);
const Result<int, String> y1 = Err('late error'); final Result<int, String> y1 = Err('late error');
expect(x1.and(y1), y1); expect(x1.and(y1), y1);
const Result<String, String> x2 = Err('early error'); final Result<String, String> x2 = Err('early error');
const Result<String, String> y2 = Ok('foo'); final Result<String, String> y2 = Ok('foo');
expect(x2.and(y2), x2); expect(x2.and(y2), x2);
const Result<void, String> x3 = Err('not a 2'); final Result<void, String> x3 = Err('not a 2');
const Result<void, String> y3 = Err('late error'); final Result<void, String> y3 = Err('late error');
expect(x3.and(y3), x3); expect(x3.and(y3), x3);
const Result<dynamic, void> x4 = Ok(2); final Result<dynamic, void> x4 = Ok(2);
const Result<dynamic, void> y4 = Ok('different result type'); final Result<dynamic, void> y4 = Ok('different result type');
expect(x4.and(y4), y4); expect(x4.and(y4), y4);
const Result<int, void> x5 = Ok(2); final Result<int, void> x5 = Ok(2);
const Result<int, void> y5 = Ok(5); final Result<int, void> y5 = Ok(5);
expect(x5.and(y5), y5); expect(x5.and(y5), y5);
}, },
); );
@ -148,24 +146,24 @@ void main() {
'or() returns res if the result is `Err`, otherwise ' 'or() returns res if the result is `Err`, otherwise '
'returns the `Ok` value of this.', 'returns the `Ok` value of this.',
() { () {
const Result<int, String> x1 = Ok(2); final Result<int, String> x1 = Ok(2);
const Result<int, String> y1 = Err('late error'); final Result<int, String> y1 = Err('late error');
expect(x1.or(y1), x1); expect(x1.or(y1), x1);
const Result<String, String> x2 = Err('early error'); final Result<String, String> x2 = Err('early error');
const Result<String, String> y2 = Ok('foo'); final Result<String, String> y2 = Ok('foo');
expect(x2.or(y2), y2); expect(x2.or(y2), y2);
const Result<void, String> x3 = Err('not a 2'); final Result<void, String> x3 = Err('not a 2');
const Result<void, String> y3 = Err('late error'); final Result<void, String> y3 = Err('late error');
expect(x3.or(y3), y3); expect(x3.or(y3), y3);
const Result<dynamic, void> x4 = Ok(2); final Result<dynamic, void> x4 = Ok(2);
const Result<dynamic, void> y4 = Ok('different result type'); final Result<dynamic, void> y4 = Ok('different result type');
expect(x4.or(y4), x4); expect(x4.or(y4), x4);
const Result<int, void> x5 = Ok(2); final Result<int, void> x5 = Ok(2);
const Result<int, void> y5 = Ok(5); final Result<int, void> y5 = Ok(5);
expect(x5.or(y5), x5); expect(x5.or(y5), x5);
}, },
); );
@ -174,10 +172,10 @@ void main() {
'contains() returns true if the result is an Ok value ' 'contains() returns true if the result is an Ok value '
'containing the given value.', 'containing the given value.',
() { () {
const Result<int, void> x1 = Ok(2); final Result<int, void> x1 = Ok(2);
expect(x1.contains(2), true); expect(x1.contains(2), true);
expect(x1.contains(3), false); expect(x1.contains(3), false);
const Result<void, String> x2 = Err('Some error message'); final Result<void, String> x2 = Err('Some error message');
expect(x2.contains(2), false); expect(x2.contains(2), false);
}, },
); );
@ -186,10 +184,10 @@ void main() {
'expect() return value if the result is an Ok value ' 'expect() return value if the result is an Ok value '
'else throw Exception', 'else throw Exception',
() { () {
const Result<int, String> x1 = Ok(2); final Result<int, String> x1 = Ok(2);
expect(x1.expect('Testing expect'), 2); expect(x1.expect('Testing expect'), 2);
const Result<int, String> x2 = Err('emergency failure'); final Result<int, String> x2 = Err('emergency failure');
expect( expect(
() => x2.expect('Testing expect'), () => x2.expect('Testing expect'),
throwsA( throwsA(
@ -205,10 +203,10 @@ void main() {
'expectErr() return value if the result is an Err value ' 'expectErr() return value if the result is an Err value '
'else throw Exception', 'else throw Exception',
() { () {
const Result<String, int> x1 = Err(2); final Result<String, int> x1 = Err(2);
expect(x1.expectErr('Testing expect err'), 2); expect(x1.expectErr('Testing expect err'), 2);
const Result<String, int> x2 = Ok('success value'); final Result<String, int> x2 = Ok('success value');
expect( expect(
() => x2.expectErr('Testing expect err'), () => x2.expectErr('Testing expect err'),
throwsA( throwsA(
@ -223,12 +221,12 @@ void main() {
test( test(
'map() transforms Ok value.', 'map() transforms Ok value.',
() { () {
const Result<bool, void> x1 = Ok(true); final Result<bool, void> x1 = Ok(true);
expect(x1.ok, true); expect(x1.ok, true);
expect(x1.map((value) => false).ok, false); expect(x1.map((value) => false).ok, false);
const Result<bool, String> x2 = Err('oops'); final Result<bool, String> x2 = Err('oops');
expect(x2.map((value) => false).isErr, true); expect(x2.map((value) => false).isErr, true);
}, },
@ -237,11 +235,11 @@ void main() {
test( test(
'mapErr() transforms Err value.', 'mapErr() transforms Err value.',
() { () {
const Result<bool, String> x1 = Ok(true); final Result<bool, String> x1 = Ok(true);
expect(x1.mapErr((value) => false).isOk, true); expect(x1.mapErr((value) => false).isOk, true);
const Result<bool, String> x2 = Err('oops'); final Result<bool, String> x2 = Err('oops');
expect(x2.err, 'oops'); expect(x2.err, 'oops');
expect(x2.mapErr((error) => 'failure').err, 'failure'); expect(x2.mapErr((error) => 'failure').err, 'failure');
@ -251,12 +249,12 @@ void main() {
test( test(
'mapAsync() transforms Ok value.', 'mapAsync() transforms Ok value.',
() async { () async {
const Result<bool, void> x1 = Ok(true); final Result<bool, void> x1 = Ok(true);
expect(x1.ok, true); expect(x1.ok, true);
expect((await x1.mapAsync((value) => Future.value(false))).ok, false); expect((await x1.mapAsync((value) => Future.value(false))).ok, false);
const Result<bool, String> x2 = Err('oops'); final Result<bool, String> x2 = Err('oops');
expect((await x2.mapAsync((value) => Future.value(false))).isErr, true); expect((await x2.mapAsync((value) => Future.value(false))).isErr, true);
}, },
@ -265,14 +263,14 @@ void main() {
test( test(
'mapErrAsync() transforms Err value.', 'mapErrAsync() transforms Err value.',
() async { () async {
const Result<bool, String> x1 = Ok(true); final Result<bool, String> x1 = Ok(true);
expect( expect(
(await x1.mapErrAsync((value) => Future.value(false))).isOk, (await x1.mapErrAsync((value) => Future.value(false))).isOk,
true, true,
); );
const Result<bool, String> x2 = Err('oops'); final Result<bool, String> x2 = Err('oops');
expect(x2.err, 'oops'); expect(x2.err, 'oops');
expect( expect(
@ -285,14 +283,14 @@ void main() {
test( test(
'either() transforms values.', 'either() transforms values.',
() { () {
const Result<bool, bool> x1 = Ok(true); final Result<bool, bool> x1 = Ok(true);
final Result<int, String> y1 = final Result<int, String> y1 =
x1.either<int, String>((value) => 1, (error) => 'error'); x1.either<int, String>((value) => 1, (error) => 'error');
expect(y1.isOk, true); expect(y1.isOk, true);
expect(y1.ok, 1); expect(y1.ok, 1);
const Result<bool, bool> x2 = Err(true); final Result<bool, bool> x2 = Err(true);
final Result<int, String> y2 = final Result<int, String> y2 =
x2.either<int, String>((value) => 1, (error) => 'error'); x2.either<int, String>((value) => 1, (error) => 'error');
@ -304,7 +302,7 @@ void main() {
test( test(
'eitherAsync() transforms values.', 'eitherAsync() transforms values.',
() async { () async {
const Result<bool, bool> x1 = Ok(true); final Result<bool, bool> x1 = Ok(true);
final Result<int, String> y1 = await x1.eitherAsync<int, String>( final Result<int, String> y1 = await x1.eitherAsync<int, String>(
(value) => Future.value(1), (value) => Future.value(1),
(error) => Future.value('error'), (error) => Future.value('error'),
@ -313,7 +311,7 @@ void main() {
expect(y1.isOk, true); expect(y1.isOk, true);
expect(y1.ok, 1); expect(y1.ok, 1);
const Result<bool, bool> x2 = Err(true); final Result<bool, bool> x2 = Err(true);
final Result<int, String> y2 = await x2.eitherAsync<int, String>( final Result<int, String> y2 = await x2.eitherAsync<int, String>(
(value) => Future.value(1), (value) => Future.value(1),
(error) => Future.value('error'), (error) => Future.value('error'),
@ -370,9 +368,9 @@ void main() {
'conditional() returns Result on true test', 'conditional() returns Result on true test',
() { () {
final Result<int, String> x1 = Result.conditional<int, String>( final Result<int, String> x1 = Result.conditional<int, String>(
false,
2, 2,
'error', 'error',
test: false,
); );
expect( expect(
x1.isErr, x1.isErr,
@ -382,9 +380,9 @@ void main() {
expect(x1.err, 'error'); expect(x1.err, 'error');
final Result<int, String> x2 = Result.conditional<int, String>( final Result<int, String> x2 = Result.conditional<int, String>(
true,
2, 2,
'error', 'error',
test: true,
); );
expect( expect(
x2.isOk, x2.isOk,
@ -399,9 +397,9 @@ void main() {
'conditionalLazy() returns Result on true test', 'conditionalLazy() returns Result on true test',
() { () {
final Result<int, String> x1 = Result.conditionalLazy<int, String>( final Result<int, String> x1 = Result.conditionalLazy<int, String>(
false,
() => 2, () => 2,
() => 'error', () => 'error',
() => false,
); );
expect( expect(
x1.isErr, x1.isErr,
@ -411,9 +409,9 @@ void main() {
expect(x1.err, 'error'); expect(x1.err, 'error');
final Result<int, String> x2 = Result.conditionalLazy<int, String>( final Result<int, String> x2 = Result.conditionalLazy<int, String>(
true,
() => 2, () => 2,
() => 'error', () => 'error',
() => true,
); );
expect( expect(
x2.isOk, x2.isOk,