locale_gen 13.0.0

Generate type-safe Dart code from JSON translation files, for Flutter apps and Dart projects, with sprintf and ICU MessageFormat support.

Changelog

13.0.0 - 2026-09-15

⚠ BREAKING CHANGES

• design spec for MessageFormat (ICU) support (#96)

Features

• design spec for MessageFormat (ICU) support (#96) (6f00a84)
• updated tools to tool (a530261)
• updated version (32eb7a8)

Bug Fixes

• format the JSON files in locale_assets_path (#100) (46898f4)
• render every format of a placeholder used more than once (#101) (3b73cb0)
• Windows asset paths (#89), release with release-please, rewrite the docs (#97) (478c628)

13.0.0-alpha.1 13.0.0-alpha.2

Feature

• MessageFormat (ICU) support: JSON values like {count, plural, one {# item} other {# items}} and Hi, {name}! now generate type-safe Dart functions with named parameters.
• ICU select, selectordinal, number, date, time, and duration arg types are supported, with locale-aware formatting via package:intl.
• Cross-locale validation: the generator warns when a non-default locale uses a different placeholder name or ICU node type than the default language for the same key.
• Optional message_format_strict: true config flag surfaces accidental sprintf usage in MessageFormat-only projects.
• MessageFormat support also lands in the Dart (non-Flutter) writer, returning a LocalizedValue with one MessageFormat-interpolated string per locale.
• The existing sprintf (%s, %d, %1$s) and JSON-object plural formats keep working unchanged; detection happens per key.
• When Localization.locale is null at runtime, MessageFormat substitution and number/date/time formatting fall back to the project's default locale (LocalizationDelegate.defaultLocale.toLanguageTag()) instead of crashing.

Known limitations

• The dynamic getTranslation(key, args:) escape hatch on the Localization class is sprintf-only. MessageFormat keys must be invoked via their generated typed functions (e.g., Localization.of(context).greeting(name: 'Alice')). Calling getTranslation with an ICU key returns the raw template string without substitution.

12.6.0

Feature

• Added support for a Dart writer.
  • Allowing you to use translations in non-Flutter projects
  • No plurals are supported for Dart writer yet

Fixed

• Project structure cleaned up

12.5.0

Updated

• Added support for Flutter 3.32.x

12.2.0 12.4.0

Updated

• Bumped intl dependency to ^0.20.0
• analysis_options.yaml updated

12.1.4

Updated

• Updated license to 2025

12.1.3

Updated

• Updated intl to support Flutter 3.22.x and above

12.1.1 12.1.2

Fixed

• Documentation old references are removed

12.1.0

Feature

• Formatting function added. (dart run locale_gen:format)

Updated

• License to BSD-3-Clause license

12.0.0 - 2023-06-05

Updated to intl 0.18.x

11.0.0 - 2023-01-11

BREAKING CHANGE!!

• After some time of using the new locale_gen package. It made our lifes harder than before. For now we reverted the
  • .of(context) removal
  • singelton implementation Other changes like sprintf, plurals and dependency updates are still in place.

10.0.0 - 2022-11-14

• Updated the signature of load to support getting the bundle to load from. Falls back to rootBubdle

9.0.1 - 2022-10-06

Updated

• Updated travis to linux from macOS

9.0.0 - 2022-10-03

Breaking

• Translations can no longer be accessed from static methods on the Localization class. Instead you now need to manually manage the different localization instances. Migration steps are described in the readme.

8.0.0 - 2022-09-24

Breaking

• Arguments are now formatted using the sprintf package. This means %d now refers to integers only. Use %f to format doubles, you can also use some format specifiers, eg: (%.2f will show 2 decimals)
• This means that the sprintf package must be added to the pubspec.yaml (at least ^6.0.2)

Added

• Support for plurals had been added, see the readme on how to use them

Updated

• Dependencies

7.0.0 - 2022-09-23

Breaking

• Removed the need of passing a context to get translations. Migration steps are described in the readme.

6.0.0 - 2022-09-20

Added

• Added support for non-positional arguments. You cannot use both positional and non-positional arguments in the same string.

5.0.0 - 2022-08-23

Fixed

• Sorting of the default language in the supported languages

4.1.2 - 2022-01-01

Fixed

• changed language code to toLanguageTag()

4.1.1 - 2021-12-16

Fixed

• Output path should also be used for the correct imports

Added

• Extra error handling for the output_path. (output_path should always start with lib/)
• Extra unit tests & refactored some code to have smaller tests

4.1.0 - 2021-12-16

Added

• Support for using an other directory instead of lib/util/locale for write all the files

4.0.0 - 2021-11-12

Breaking

• Dart 2.14.0 is minimum dart version
• Fixed an issue where kDebugMode moved to another import

3.7.0 - 2021-11-02

• Added better import sorting (alphabetic) so the analyzer won't break everytime

3.6.1 - 2021-10-12

• Issue where an exception was thrown even when it was not needed.

3.6.0 - 2021-10-12

Fixed

• #53: Issue where a carriage return \r would generate invalid documentation
• #52: Unnecessary string interpolation for '$key' in localization.dart

Added

• #39: Better generated documentation for arguments
• #56: Option to override the localizations. Pass a LocalizationOverrides to the LocalizationDelegate. Refreshing & managing the cached localizations should be done by the developer.

3.5.0 - 2021-10-06

Added

• locale that was used to initialize your Localization is now also included in localization.dart

3.4.1 - 2021-05-07

Fixed

• the default language generation
• the supported language list generation

3.4.0 - 2021-05-06

Added

• #45 support for country codes & languages

3.3.0 - 2021-04-07

Added

• #48 useCaching configuration for fetching the json translation files

Fixed

• #46 default path variables (asset dir, local asset dir, output dir)

3.2.1 - 2021-03-30

Fixed

• #43 Newline documentation issue

3.2.0 - 2021-03-30

Added

• #42 Migrated strict mode code
• #42 Generate strict mode code
• #36 Added support generating documentation so you can see translations in your IDE
• #37 Added config option to configure which languages should be used for generating documentation code

3.1.0 - 2021-03-25

Added

• #34 Support for skipping a locale at runtime. example: only use dutch in alpha but not in beta & production

3.0.0 - 2021-03-07

Added

• #32 Nullsafety implementation. Support for flutter 2.0 & dart 2.12.0

Removed

• #32 nullsafe flag is removed because from this version we are targeting 2.12 which will use nullsafety by default

2.1.0 - 2021-02-09

• Added option to generate null safety compatible code

2.0.5 - 2020-10-06

Fixed

• #24: error when using locale_asset_path in combination with the icapps_translations package

2.0.4 - 2020-10-03

Fixed

• Version bump packages

2.0.3 - 2020-10-03

Added to repo

• Added travis ci integration

2.0.2 - 2020-10-03

Fixed

• Android embedding v2

2.0.1 - 2020-10-03

Updated

• Documentation updated

2.0.0 - 2020-10-03

Refactor

• Added support for the usage of this package in other once. Mainly because of icapps_translations

Added

• Strict mode
• Support for a multi module architecture

1.0.0 - 2020-03-28

Added

• Localization keys support (better support for testing)

Breaking

• isInTest => showLocalizationKeys Behaviour is still the same.

0.2.0 - 2019-10-13

Added

• Test support

Fixed

• Removed the unneeded log

0.1.1 - 2019-08-19

Fixed

• Fixed documentation about arguments

0.1.0 - 2019-06-22

Added

• Support for arguments

Fixed

• Dart formatting

0.0.2 - 2019-06-12

Added

• Updated README.md

0.0.1 - 2019-06-12

Added

• Initial release