import_lint

Why import_lint?

The import_lint package defines rules to restrict imports and performs static analysis. It was inspired by eslint/no-restricted-paths.

😻 Usage

1. Add import_lint as a dev_dependencies in pubspec.yamls.

flutter pub add --dev import_lint

or

dart pub add --dev import_lint

2. You have lints configured in an analysis_options.yaml file at the root of your project.

• target: Define the file paths of the targets to be restricted using glob patterns.
• from: Define the paths that are not allowed to be used in imports using glob patterns.
• except: Define the exception paths for the 'from' rule using glob patterns.

Example of analysis_options.yaml

plugins:
  import_lint: <version number>

import_lint:
  rules:
    example_rule:
      target: "package:example/target/*.dart"
      from: "package:example/from/*.dart"
      except: ["package:example/from/except.dart"]
    self_rule:
      target: "package:example/self/*.dart"
      from: "package:example/self/*.dart"
      except: []
    only_rule:
      target: "package:example/*[!only]/*.dart"
      from: "package:example/only_from/*.dart"
      except: []
    package_rule:
      target: "package:example/**/*.dart"
      from: "package:import_lint/*.dart"
      except: []
    # add custom rules...

Note: import_lint requires Dart 3.10 or later (analyzer plugin support was added in Dart 3.10 / Flutter 3.38). The top-level plugins: section is the new analyzer plugin system. After any change to the plugins: section, the Dart Analysis Server must be restarted to see the effects (VS Code: Dart: Restart Analysis Server).

By adding import_lint plugin to get the warnings directly in your IDE by configuring.

3. run import_lint(CLI Support)

flutter run import_lint

or

dart run import_lint

Example

example/analysis_options.yaml

plugins:
  import_lint:
    path: ..

import_lint:
  rules:
    example_rule:
      target: "package:example/target/*.dart"
      from: "package:example/from/*.dart"
      except: ["package:example/from/except.dart"]
    self_rule:
      target: "package:example/self/*.dart"
      from: "package:example/self/*.dart"
      except: []
    only_rule:
      target: "package:example/*[!only]/*.dart"
      from: "package:example/only_from/*.dart"
      except: []
    package_rule:
      target: "package:example/**/*.dart"
      from: "package:import_lint/*.dart"
      except: []

files

example/lib

output

$ dart run import_lint

Analyzing...
   warning • /example/lib/not/1.dart:1:8 • package:example/only_from/1.dart • only_rule
   warning • /example/lib/target/1.dart:2:8 • package:example/from/test.dart • example_rule
   warning • /example/lib/self/1.dart:1:8 • package:example/self/2.dart • self_rule
   warning • /example/lib/package/1.dart:1:8 • package:import_lint/import_lint.dart • package_rule

4 issues found.

Option

Rule Severities

To change the severity of a rule, add a severity key to the rule configuration.

• warning (default)
• error (exit code 1 when lint is found)

import_lint:
  severity: "error"
  rules: ...

Note on IDE severity: The severity: "error" setting is honored by dart run import_lint (exit code 1). In the IDE, analysis_server_plugin registers a fixed warning severity. To see import_lint errors as errors in the IDE, add this to analysis_options.yaml:

analyzer:
  errors:
    import_lint: error

Contribution

Welcome PRs!

To develop locally, clone the repo and enable the plugin from a local path in your host project's analysis_options.yaml:

plugins:
  import_lint:
    path: /path/to/your/import-lint
    diagnostics:
      import_lint: true

For CLI use (dart run import_lint), also add it under dev_dependencies:

dev_dependencies:
  import_lint:
    path: /path/to/your/import-lint

Then run dart pub get in the host project and restart the Dart Analysis Server. No separate tools/analyzer_plugin directory is needed — the plugin entry point is lib/main.dart in this package.