Check Unused L10n

Checks unused Dart class members, that encapsulates the app's localized values.

An example of such class:

class ClassWithLocalization {
  String get title {
    return Intl.message(
      'Hello World',
      name: 'title',
      desc: 'Title for the Demo application',
      locale: localeName,
    );
  }
}

Read more about this localization approach in the Flutter docs.

info

By default, the command searches for classes that end with I18n, but you can override this behavior with --class-pattern argument.

To execute the command, run:

$ dcm check-unused-l10n lib # or dcm ul lib

Full command description:

Usage: dcm check-unused-l10n [arguments] <directories>
-h, --help                                       Print this usage information.


-p, --class-pattern=<I18n$>                      The pattern to detect classes providing localization
                                                 (defaults to "I18n$")


-r, --reporter=<console>                         Analysis output format.
                                                 [console (default), json, codeclimate, gitlab, checkstyle]
-a, --absolute-path                              Show absolute paths in console reporter output.
    --json-path=<path/to/file.json>              Path to the JSON file with the analysis output.


-c, --print-config                               Print resolved config.


    --root-folder=<./>                           Root folder.
                                                 (defaults to the current directory)
    --sdk-path=<directory-path>                  Dart SDK directory path.
                                                 If the project has a `.fvm/flutter_sdk` symlink, it will be used if the SDK is not found.
    --exclude=<{**/*.g.dart,**/*.freezed.dart}>  File paths in Glob syntax to be exclude.
                                                 (defaults to "{**/*.g.dart,**/*.freezed.dart}")


    --no-congratulate                            Don't show output even when there are no issues.


    --verbose                                    Show verbose logs.


    --ci-key                                     The license key to run on CI server. Can be provided via DCM_CI_KEY env variable.
    --email                                      The email used to purchase the license. Can be provided via DCM_EMAIL env variable.


    --no-analytics                               Disable sending anonymous usage statistics.


    --[no-]fatal-unused                          Treat find unused l10n as fatal.
                                                 (defaults to on)

Output example

Console

Use --reporter=console to enable this format.

JSON

The reporter prints a single JSON object containing meta information and the unused file paths. Use --reporter=json to enable this format.

The root object fields are

• formatVersion - an integer representing the format version (will be incremented each time the serialization format changes)
• timestamp - a creation time of the report in YYYY-MM-DD HH:MM:SS format
• unusedLocalizations - an array of unused files

{
  "formatVersion": 2,
  "timestamp": "2021-04-11 14:44:42",
  "unusedLocalizations": [
    {
      ...
    },
    {
      ...
    },
    {
      ...
    }
  ]
}

The unusedLocalizations object fields are

• path - a relative path of the unused file
• className - a name of the class that has unused members
• issues - an array of issues detected in the target class

{
  "path": "lib/src/some/class.dart",
  "className": "class",
  "issues": [
    ...
  ],
}

The issue object fields are

• memberName - unused class member name
• offset - a zero-based offset of the class member location in the source
• line - a zero-based line of the class member location in the source
• column - a zero-based column of class member the location in the source

{
  "memberName": "someGetter",
  "offset": 156,
  "line": 7,
  "column": 1
}

GitLab

Reports unused l10n issues in merge requests based on Code Quality custom tool. Use --reporter=gitlab to enable this format.

Checkstyle

Use --reporter=checkstyle to enable this format.

<?xml version="1.0"?>
<checkstyle version="10.0">
  <file name="example.dart">
    <error line="5" column="3" severity="warning" message="Unused method someMethod()" source="unused-localization-issue"/>
  </file>
</checkstyle>