gherkin-assembler

gherkin-assembler

It allows to convert Gherkin AST to feature file string.

API

objectToAST(document)

The objectToAST API method converts the given Gherkin object into GherkinDocument object.

A complete sample Gherkin object can be found here: Complete Gherkin object.

Params:

• {Object} documet - a single Gherkin object

Returns: {GherkinDocument}

format(document, options)

The format API method formats the given Gherkin Document(s) to string (which could be written out to feature file(s)).

Params:

• {GherkinDocument|Array<GherkinDocument>} document - a single or multiple Gherkin Documents given in it's AST model.
• {AssemblerConfig} options - options to set attributes of formatting.

Returns: {string|Array<string>}

'use strict';

const fs = require('fs');
const assembler = require('gherkin-assembler');
const document = assembler.objectToAST(require('./login.ast.json'));

fs.writeFileSync('./login.feature', assembler.format(document), 'utf8');

AssemblerConfig

By passing an AssemblerConfig object to format method (or other Ast type methods where it's applicable) it can be set, how feature file text is rendered.

Option	Description	Default
oneTagPerLine	Should tags rendered separately, one by line?	false, i.e. all tag of a scenario, feature, etc will be rendered in the same line
separateStepGroups	Should step groups (when-then) be separated?	false
compact	Should empty lines be skipped, removed from the result?	false, i.e. there will be empty lines in appropriate places
lineBreak	The line break character(s).	\n, i.e. it uses Unix line break, to set Windows style, set \r\n
indentation	The indentation character(s).	' ', i.e. it uses two space character to add indentation where it's appropriate

AST

The API provides types to be able to handle different parts of Gherkin feature files.

'use strict';
const {AST} = require('gherkin-assembler');
console.log(Object.keys(AST));
// Background,...,Feature,GherkinDocument,...,Tag

GherkinDocument

Model of a complete Gherkin document, i.e. feature file.

Fields

• {Feature} feature - The feature which this document contains.

Methods

• new GherkinDocument() : GherkinDocument - Creates a new instance.
• {GherkinDocument}.toString({AssemblerConfig} [options]) : string - Converts the document to string, i.e. formats it.
• {GherkinDocument}.clone() : GherkinDocument - Clones the document.
• GherkinDocumnet.parse({Object} object) : GherkinDocument - Parses the given GherkinDocument object to a GherkinDocument.

Feature

Model of a Gherkin feature.

Feature: Hello world
  As a smo
  I want to do smth
  So that I am smth

Fields

• {string} keyword - The keyword of the feature, e.g. "Feature".
• {string} name - The name of the feature, e.g. "Hello world".
• {string} description - The description of the feature, e.g. "As a smo\nI want to do smth\nSo that I am smth".
• {string} language - Tne of the supported Gherkin language, default: "en".
• {Array<Tag>} tags - Tags of the feature.
• {Array<Background|Scenario|ScenarioOutline>} elements - The elements of the feature, i.e. scenario, background or scenario outline.

Methods

• new Feature(keyword, name, description, language) : Feature - Creates a new Feature object, with the given values.
• {Feature}.toString({AssemblerConfig}) : string - Converts the feature to string, i.e. formats it.
• {Feature}.clone() : Feature - Clones the feature.
• Feature.parse({Object} object) : Feature - Parses the given Feature object to a Feature.

Background

Model of a Gherkin Background scenario.

Background: Some background steps
  Given this is a given step
  And this is a given step too
  When this is a when step
  And this is a when step too
  Then it should be a then step
  And it should be a then step too

Fields

• {string} keyword - The keyword of the background, e.g. "Background".
• {string} name - The name of the background, e.g. "Some background steps".
• {string} description - The description of the background.
• {Array<Step>} steps - The steps of the background.

Methods

• new Background(keyword, name, description) : Background - Creates a new Background object, with the given values.
• {Background}.useNormalStepKeywords() - Sets the keywords of all step to normal keywords, i.e. Given, When, Then.
• {Background}.useReadableStepKeywords() - Sets the keywords of steps to more readable ones, if applicable, i.e. replaces multiple normal keywords with And keyword.
• {Background}.toString({AssemblerConfig}) : string - Converts the background to string, i.e. formats it.
• {Background}.clone() : Background - Clones the background.
• Background.parse({Object} object) : Background - Parses the given Background object to a Background.

Scenario

Model of a Gherkin scenario.

@tag2 @tag3
Scenario: Name of scenario
Description of the scenario

  Given this is a given step
  And this is a given step too

Fields

• {string} keyword - The keyword of the scenario, e.g. "Scenario".
• {string} name - The name of the scenario, e.g. "Name of scenario".
• {string} description - The description of the scenario, e.g. "Description of the scenario".
• {Array<Step>} steps - The steps of the scenario.
• {Array<Tag>} tags - Tags of the scenario.

Methods

• new Scenario(keyword, name, description) : Scenario - Creates a new Scenario object, with the given values.
• {Scenario}.useNormalStepKeywords() - Sets the keywords of all step to normal keywords, i.e. Given, When, Then.
• {Scenario}.useReadableStepKeywords() - Sets the keywords of steps to more readable ones, if applicable, i.e. replaces multiple normal keywords with And keyword.
• {Scenario}.toString({AssemblerConfig}) : string - Converts the scenario to string, i.e. formats it.
• {Scenario}.clone() : Scenario - Clones the scenario.
• Scenario.parse({Object} object) : Scenario - Parses the given Scenario object to a Scenario.

ScenarioOutline

Model of a Gherkin Scenario outline.

@tag2 @tag(3)
Scenario Outline: Name of outline <key>
  Given this is a given step
  And this is a given step too
  When this is a when step <key>
  And this is a when step too
  Then it should be a then step
  And it should be a then step too

@tagE1
  Examples: First examples
    | key    |
    | value1 |

Fields

• {string} keyword - The keyword of the scenario outline, e.g. "Scenario Outline".
• {string} name - The name of the scenario outline, e.g. "Name of outline <key>".
• {string} description - The description of the scenario outline.
• {Array<Step>} steps - The steps of the scenario outline.
• {Array<Tag>} tags - Tags of the scenario outline.
• {Array<Examples>} examples - Examples of the scenario outline.

Methods

• new ScenarioOutline(keyword, name, description) : ScenarioOutline - Creates a new ScenarioOutline object, with the given values.
• {ScenarioOutline}.useNormalStepKeywords() - Sets the keywords of all step to normal keywords, i.e. Given, When, Then.
• {ScenarioOutline}.useReadableStepKeywords() - Sets the keywords of steps to more readable ones, if applicable, i.e. replaces multiple normal keywords with And keyword.
• {ScenarioOutline}.toString({AssemblerConfig}) : string - Converts the scenario outline to string, i.e. formats it.
• {ScenarioOutline}.clone() : ScenarioOutline - Clones the scenario outline.
• ScenarioOutline.parse({Object} object) : ScenarioOutline - Parses the given ScenarioOutline object to a ScenarioOutline.

Examples

Model of a Gherkin Scenario outline Examples table.

@tagE1
  Examples: First examples
    | key    |
    | value1 |

Fields

• {string} keyword - The keyword of the examples table, e.g. "Examples".
• {string} name - The name of the examples table, e.g. "First examples".
• {Array<Tag>} tags - Tags of the examples table.
• {TableRow} header - The header row of the examples table, with column name(s).
• {Array<TableRow>} body - The data rows of the examples table.

Methods

• new Examples(keyword, name, description) : Examples - Creates a new Examples object, with the given values.
• {Examples}.toString({AssemblerConfig}) : string - Converts the examples table to string, i.e. formats it.
• {Examples}.clone() : Examples - Clones the examples table.
• Examples.parse({Object} object) : Examples - Parses the given Examples object to an Examples.

Step

Model of a Gherkin step.

Given this is a given step
And this is a given step too

Fields

• {string} keyword - The keyword of the step, e.g. "Given".
• {string} text - The text of the step, e.g. "this is a given step".
• {DocString|DataTable} argument - The argument of the step if there is any. It could be a DocString or a DataTable.

Methods

• new Step(keyword, text) : Step - Creates a new Step object, with the given values.
• {Step}.toString({AssemblerConfig}) : string - Converts the step to string, i.e. formats it.
• {Step}.clone() : Step - Clones the step.
• Step.parse({Object} object) : Step - Parses the given Step object to a Step.

Tag

Model of a Gherkin tag (annotation).

@tag(1)

Fields

• {string} value - The tag itself, e.g. "@tag(1)".

Methods

• new Tag(value) : Tag - Creates a new Tag object, with the given values.
• {Tag}.toString() : string - Converts the tag to string, i.e. formats it.
• {Tag}.clone() : Tag - Clones the tag.
• Tag.parse({Object} object) : Tag - Parses the given Tag object to a Tag.

DocString

Model of a Gherkin DocString step argument.

And this is a when step with doc string
  """
  Hello world
  Hello World
  hello World
  hello world
  """

Fields

• {string} content - The content of the docString, e.g. "Hello world\nHello World...".

Methods

• new DocString(value) : DocString - Creates a new DocString object, with the given values.
• {DocString}.toString({AssemblerConfig}) : string - Converts the docString to string, i.e. formats it.
• {DocString}.clone() : DocString - Clones the docString.
• DocString.parse({Object} object) : DocString - Parses the given DocString object to a DocString.

DataTable

Model of a Gherkin DocString step argument.

And this is a when step with data table too
  | col1 | col2 |
  | val1 | val2 |
  | val3 | val4 |

Fields

• {Array<TableRow>} rows - The rows of the data table.

Methods

• new DataTable(rows) : DataTable - Creates a new DataTable object, with the given values.
• {DataTable}.toString({AssemblerConfig}) : string - Converts the data table to string, i.e. formats it.
• {DataTable}.clone() : DataTable - Clones the data table.
• DataTable.parse({Object} object) : DataTable - Parses the given DataTable object to a DataTable.

TableRow

Model of a row in Gherkin DataTable or Examples.

And this is a when step with data table too
  | col1 | col2 |
  | val1 | val2 |
  | val3 | val4 |

Fields

• {Array<TableCell>} cells - The cells of the table row.

Methods

• new TableRow(cells) : TableRow - Creates a new TableRow object, with the given values.
• {TableRow}.toString({AssemblerConfig}) : string - Converts the table row to string, i.e. formats it.
• {TableRow}.clone() : TableRow - Clones the table row.
• TableRow.parse({Object} object) : TableRow - Parses the given TableRow object to a TableRow.

TableCell

Model of a cell in a Gherkin TableRow.

And this is a when step with data table too
  | col1 | col2 |
  | val1 | val2 |
  | val3 | val4 |

Fields

• {string} value - The value of the cell, e.g. "col1".

Methods

• new TableCell(value) : TableCell - Creates a new TableCell object, with the given values.
• {TableCell}.toString() : string - Converts the table cell to string, i.e. formats it.
• {TableCell}.clone() : TableCell - Clones the table cell.
• TableCell.parse({Object} object) : TableCell - Parses the given TableCell object to a TableCell.

Parsing feature files to Gherkin object

Although this package does not contain method to parse feature file to Gherkin object, you can use the gherkin subpackage of CucumberJS.

'use strict';
const fs = require('fs');
const {Parser} = require('gherkin');
const parser = new Parser();
const document = parser.parse(fs.readFileSync('./login.feature'));

// use objectToAST and format to write it to file again