Configuration

To configure the package add a flutterando_metrics entry to analysis_options.yaml. This configuration is used by both CLI and the analyzer plugin.

analysis_options.yaml

flutterando_metrics:
  extends:
    - ... # configures the list of preset configurations
  metrics:
    - ... # configures the list of reported metrics
  metrics-exclude:
    - ... # configures the list of files that should be ignored by metrics
  rules:
    - ... # configures the list of rules
  rules-exclude:
    - ... # configures the list of files that should be ignored by rules
  anti-patterns:
    - ... # configures the list of anti-patterns

Basic config example:

analysis_options.yaml

flutterando_metrics:
  metrics:
    cyclomatic-complexity: 20
    number-of-parameters: 4
    maximum-nesting-level: 5
  metrics-exclude:
    - test/**
  rules:
    - newline-before-return
    - no-boolean-literal-compare
    - no-empty-block
    - prefer-trailing-comma
    - prefer-conditional-expressions
    - no-equal-then-else
  anti-patterns:
    - long-method
    - long-parameter-list

Extending an existing configuration preset

To extend an existing preset add a reference to the .yaml file with the preset in the extends entry. For example:

analysis_options.yaml

flutterando_metrics:
  extends:
    - package:flutterando_metrics/presets/all.yaml
  rules:
    - arguments-ordering:
        child-last: true
    - avoid-banned-imports: false

All predefined preset can be found here.

Configuring a metrics entry

To enable a metric add its id to the metrics entry in the analysis_options.yaml. All metrics can take a threshold value. If no value was provided, the default value will be used.

Configuring a metrics-exclude entry

To exclude files from a metrics report provide a list of regular expressions for ignored files. For example:

analysis_options.yaml

flutterando_metrics:
  metrics-exclude:
    - test/**
    - lib/src/some_file.dart

Configuring a rules entry

To enable a rule add its id to the rules entry. All rules have severity which can be overridden with severity config entry. For example,

analysis_options.yaml

flutterando_metrics:
  rules:
    - newline-before-return:
        severity: style

will set severity to style. Available severity values:

• none
• style
• performance
• warning
• error

Rules with a configurable badge have additional configuration, check out their docs for more information.

Configuring a rules-exclude entry

To exclude files from a rules analysis provide a list of regular expressions for ignored files. For example:

analysis_options.yaml

flutterando_metrics:
  rules-exclude:
    - test/**
    - lib/src/some_file.dart

Configuring an anti-pattern entry

To enable an anti-pattern add its id to the anti-patterns entry. All anti-pattern have severity which can be overridden with severity config entry. For example,

analysis_options.yaml

flutterando_metrics:
  anti-patterns:
    - long-method:
        severity: warning

will set severity to warning.

Ignoring a rule or anti-pattern

If a specific rule or anti-pattern warning should be ignored, it can be flagged with a comment. For example,

// ignore: no-empty-block
void emptyFunction() {}

tells the analyzer to ignore this instance of the no-empty-block warning.

End-of-line comments are supported as well. The following communicates the same thing:

void emptyFunction() {} // ignore: no-empty-block

To ignore a rule for an entire file, use the ignore_for_file comment flag. For example,

// ignore_for_file: no-empty-block
...

void emptyFunction() {}

tells the analyzer to ignore all occurrences of the kebab-case-types warning in this file.

It's the same approach that the dart linter package use.

Additionally, exclude entry for the analyzer config can be used to ignore files. For example,

analysis_options.yaml

analyzer:
  exclude:
    - "example/**"
    - "build/**"
    - "**/*.g.dart"
    - "**/*.freezed.dart"

will work both for the analyzer and for this plugin.

If you want a specific rule to ignore files, you can configure exclude entry for it. For example,

analysis_options.yaml

flutterando_metrics:
  rules:
    - no-equal-arguments:
        exclude:
          - test/**

and similar example for anti-pattern,

analysis_options.yaml

flutterando_metrics:
  anti-patterns:
    - long-method:
        exclude:
          - test/**