Basic-Smell-Options.md

Basic Smell Options

Introduction

Every smell detector in Reek offers at least the following configuration options:

Option	Value	Effect
enabled	Boolean	Determines whether the smell detector is active. Defaults to true
exclude	an array of strings that will be converted into regular expressions	Ignores any context whose full description matches any element of this array.

The file docs/defaults.reek.yml (shipped with the Reek gem) lists any default exclusions for each smell.

Examples

An easy one:

To stop Reek reporting smells in any method called write you might create a configuration file containing this:

DuplicateMethodCall:
  exclude:
  - write

Internally Reek will convert this to the Regexp /write/.

A more sophisticated one:

FeatureEnvy:
  exclude:
    - "MyModel#do_things"
    - "MyHelper"
    - "ApplicationController#respond"

This would not report FeatureEnvy for the instance method MyModel#do_things, the whole module MyHelper and the respond instance method of ApplicationController

Advanced configuration

Sometimes just strings are not enough for configuration. E.g. consider this code sample:

class Klass
  def foo1; end
  def foo1bar; end
end

Both "Klass#foo1" and "Klass#foo1bar" will smell of UncommunicativeMethodName. Now let's assume you are ok with "Klass#foo1" but not "Klass#foo1bar". Just having this configuration

UncommunicativeMethodName:
  exclude:
    - "Klass#foo1"

wouldn't work because now "Klass#foo1bar" wouldn't smell as well.

For this reason Reek has a special syntax that allows you to use regexes by using a forward slash at the beginning and the end of the string. Everything within the forward slashes will be loaded as a regex.

A possible configuration that hat excludes "Klass#foo1" from this scan but not "Klass#foo1bar" could look like this:

UncommunicativeMethodName:
  exclude:
    - "/Klass#foo1$/"

Reek 4

In Reek 4 you could also pass regexes to exclude, meaning this was perfectly valid as well:

DuplicateMethodCall:
  exclude:
    - !ruby/regexp /write/

Support for this has been scrapped with Reek 5 to make the Reek configuration more yaml standard compliant. You can still pass in regexes, you just have to wrap them into a string. Please see "Advanced configuration" above.