Skip to main content

Check Unused Files

Checks unused *.dart files.

To execute the command, run:

$ dcm check-unused-files lib # or dcm uf lib

Full command description:

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

-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.

--monorepo Include publicly exported files into the check.

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

-d, --delete-files Delete all unused files.

Suppressing the command

In order to suppress the command add ignore_for_file: unused-files to the beginning of a file.

Cyclic usage detection

If you have several files that reference each other, but are not referenced by other files and technically are unused, the command will only detect 1 level of cyclic usage.

Monorepo support


By default, this command treats all files that are exported from the package as used. It uses check-exports-completeness results and won't report even transitive public entities that are not exported directly.

This command also follows this convention of locating implementation files in the lib/src/ folder. If you don't follow this convention, you will need to pass the --monorepo flag for this command to work.

To disable this behavior use --monorepo flag. This might be useful when all the packages in your repository are only used within the repository and are not published to the pub.

Overriding monorepo mode for a particular package

To override the monorepo mode for a particular package, set the monorepo entry in the analysis_options.yaml.

For example, if publicly exported files of a particular package are not expected to be changed, setting the monorepo entry to false and passing the --monorepo option will enable the monorepo mode for all other packages, but not the one with monorepo: false.

Output example


Use --reporter=console to enable this format.



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
  • unusedFiles - an array of unused files
  • automaticallyDeleted - an indication of unused files being automatically deleted
"formatVersion": 2,
"timestamp": "2021-04-11 14:44:42",
"unusedFiles": [
"automaticallyDeleted": false

The unusedFiles object fields are

  • path - a relative path of the unused file
  • usedOnlyInTests a boolean value that indicates files used only by test files
"path": "lib/src/some/file.dart",
"usedOnlyInTests": false


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


Use --reporter=checkstyle to enable this format.

<?xml version="1.0"?>
<checkstyle version="10.0">
<file name="example.dart">
<error line="0" message="Unused file" severity="warning" source="unused-file-issue"/>