rules

Rules

Rules can either be specified in your gherklin.config.ts file, or inline when you call the Runner

Rule configuration takes the form of a string key and a value. Every rule supports off as a value, turning the rule off (which is the same as excluding it from the configuration).

However, depending on the rule, there may be more configuration values.

If a rule does not specify a severity, it will default to warn.

The following is a list of rules and whether or not they are fixable with the fix configuration option.

Name	Rule	Fixable
Allowed Tags	allowed-tags	❌
Indentation	indentation	✅
Max Scenarios	max-scenarios	❌
New Line at EOF	new-line-at-eof	✅
No Background Only	no-background-only	❌
No Dupe Features	no-dupe-features	❌
No Dupe Scenarios	no-dupe-scenerios	❌
No Similar Scenarios	no-similar-scenerios	❌
No Empty File	no-empty-file	❌
No Trailing Spaces	no-trailing-spaces	✅
No Unnamed Scenarios	no-unnamed-scenarios	❌
Keywords in Logical Order	keywords-in-logical-order	❌
No Single Example Outline	no-single-example-outline	❌
No Full Stop	no-full-stop	✅
No Scenario Splat	no-scenario-splat	❌
No Typographer Quotes	no-typographer-quotes	✅
Background Setup Only	background-setup-only	❌
Given After Background	given-after-backgroundy	❌
No Inconsistent Quotes	no-inconsistent-quotes	✅
Filename Snake Case	filename-snake-case	❌
Filename Kebab Case	filename-kebab-case	❌
Unique Examples	unique-examples	❌
Feature Description	feature-description	❌
Scenario Action	scenario-action	❌
Scenario Verification	scenario-verification	❌
Scenario Name Length	scenario-name-length	❌

Allowed Tags

Restrict which tags are allowed in feature files by specifying a list. This rule checks for valid tags at the feature level and scenario level.

Examples

Enable the rule with arguments

export default {
  rules: {
    'allowed-tags': ['@development'],
  },
}

Enable the rule and set severity

export default {
  rules: {
    'allowed-tags': ['error', '@development'],
  }
}

---

Indentation

Configure how many spaces are allowed for different Gherkin keywords.

Examples

Enable the rule with arguments

export default {
  rules: {
    indentation: {
      feature: 1,
      background: 3,
      scenario: 3,
      step: 5,
      examples: 5,
      given: 5,
      when: 5,
      then: 5,
      and: 5,
      but: 5,
      exampleTableHeader: 7,
      exampleTableBody: 7,
    }
  }
}

Enable the rule and set severity

export default {
  rules: {
    indentation: [
      'error',
      {
        feature: 1,
        background: 3,
        scenario: 3,
        step: 5,
        examples: 5,
        given: 5,
        when: 5,
        then: 5,
        and: 5,
        but: 5,
        exampleTableHeader: 7,
        exampleTableBody: 7,
      }
    ]
  }
}

---

Max Scenarios

Specify the maximum number of scenarios allowed per feature.

Examples

Enable the rule with arguments

export default {
  rules: {
    'max-scenarios': 2,
  }
}

Enable the rule and set severity

export default {
  rules: {
    'max-scenarios': [
      'error',
      2,
    ]
  }
}

---

New Line at EOF

Expect a new line at the end of each file.

Examples

Enable the rule

export default {
  rules: {
    'new-line-at-eof': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'new-line-at-eof': 'error',
  }
}

---

No Background Only

Don't allow features which only have a background.

Examples

Enable the rule

export default {
  rules: {
    'no-background-only': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'no-background-only': 'error',
  }
}

---

No Dupe Features

Don't allow features to have the same name across all files.

Examples

Enable the rule

export default {
  rules: {
    'no-dupe-features': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'no-dupe-features': 'error',
  }
}

---

No Dupe Scenarios

Don't allow scenarios to have the same name across all files.

Examples

Enable the rule

export default {
  rules: {
    'no-dupe-scenarios': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'no-dupe-scenarios': 'error',
  }
}

---

No Empty File

Don't allow feature files to be empty.

Examples

Enable the rule

export default {
  rules: {
    'no-empty-file': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'no-empty-file': 'error',
  }
}

---

No Trailing Spaces

Don't allow trailing spaces at the end of lines.

Examples

Enable the rule

export default {
  rules: {
    'no-trailing-spaces': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'no-trailing-spaces': 'error',
  }
}

---

No Unnamed Scenarios

Expect every scenario to be named.

Examples

Enable the rule

export default {
  rules: {
    'no-unnamed-scenarios': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'no-unnamed-scenarios': 'error',
  }
}

Keywords in Logical Order

Asserts that keywords follow the logical order or Given, When, Then.

Examples

Enable the rule

export default {
  rules: {
    'keywords-in-logical-order': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'keywords-in-logical-order': 'error',
  }
}

No Similar Scenarios

Compares each scenario with each other scenario to see if they are similar. Compares the Levenshtein distance between one scenarios keyword + text with the other scenarios keyword + text. The argument passed to this rule's configuration is the percentage threshold for similarity.

Examples

Enable the rule

export default {
  rules: {
    'no-similar-scenarios': 'on',
  }
}

Enable the rule with arguments

export default {
  rules: {
    'no-similar-scenarios': 85,
  }
}

Enable the rule and set severity

export default {
  rules: {
    'no-similar-scenarios': 'error',
  }
}

Set severity and arguments

export default {
  rules: {
    'no-similar-scenarios': ['error', 99],
  }
}

No Single Example Outline

Checks Scenario Outlines that only have one example. These should be converted to simple Scenarios.

Examples

Enable the rule

export default {
  rules: {
    'no-single-example-outline': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'no-single-example-outline': 'error',
  }
}

No Full Stop

Full stops (period) end sentences and don't convey a flow of steps.

Examples

Enable the rule

export default {
  rules: {
    'no-full-stops': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'no-full-stops': 'error',
  }
}

No Scenario Splat

Splat steps (*) are useful for setup, which should occur in the background

Examples

Enable the rule

export default {
  rules: {
    'no-scenario-splat': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'no-scenario-splat': 'error',
  }
}

No Typographer Quotes

"Smart quotes" can be a result of copy/pasting from other programs and may not be intended.

Examples

Enable the rule

export default {
  rules: {
    'no-typographer-quotes': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'no-typographer-quotes': 'error',
  }
}

Enable the rule and set argument.

The argument is used as a replacement when the fix option is specified.

export default {
  rules: {
    'no-typographer-quotes': ['error', "\""],
  }
}

Background Setup Only

Background should be used for set up only, so should only include "Given" or splats (*).

Examples

Enable the rule

export default {
  rules: {
    'background-setup-only': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'background-setup-only': 'error',
  }
}

Given After Background

If you have a background, it should be used to set up scenarios, so there's no need for scenarios to also use "Given"

Examples

Enable the rule

export default {
  rules: {
    'given-after-background': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'given-after-background': 'error',
  }
}

No Inconsistent Quotes

Prefer consistency with quotes used.

Examples

Enable the rule

export default {
  rules: {
    'no-inconsistent-quotes': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'no-inconsistent-quotes': 'error',
  }
}

Enable the rule and set argument.

The argument is used as a replacement when the fix option is specified.

export default {
  rules: {
    'no-inconsistent-quotes': ['error', "\""],
  }
}

Filename Snake Case

File names should be in snake_case.

Examples

Enable the rule

export default {
  rules: {
    'filename-snake-case': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'filename-snake-case': 'error',
  }
}

Filename Kebab Case

File names should be in kebab-case.

Examples

Enable the rule

export default {
  rules: {
    'filename-kebab-case': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'filename-kebab-case': 'error',
  }
}

Unique Examples

Examples should have a unique name if there are more than 1 in a scenario outline.

Examples

Enable the rule

export default {
  rules: {
    'unique-examples': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'unique-examples': 'error',
  }
}

Feature Description

Features should have descriptions to outline what behaviour they are testing.

Examples

Enable the rule

export default {
  rules: {
    'feature-description': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'feature-description': 'error',
  }
}

Scenario Action

Scenarios should have a "When" to denote an action

Examples

Enable the rule

export default {
  rules: {
    'scenario-action': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'scenario-action': 'error',
  }
}

Scenario Verification

Scenarios should have a "Then" to denote verification of an action

Examples

Enable the rule

export default {
  rules: {
    'scenario-verification': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'scenario-verification': 'error',
  }
}

Scenario Name Length

Scenarios should have a length no longer than specified.

Examples

Enable the rule

export default {
  rules: {
    'scenario-name-length': 'on',
  }
}

Enable the rule and set severity

export default {
  rules: {
    'scenario-name-length': 'error',
  }
}

Enable the rule and set args

export default {
  rules: {
    'scenario-name-length': ['error', 99],
  }
}