mocha-gherkin

Pipe a feature... Get a mocha

Gherkin syntax → Mocha BDD specs

Streaming

The parser is a readable / writable stream, so you can pipe any stream connected to a valid feature like:

Feature: Example feature
  As a user of cucumber.js
  I want to have documentation on cucumber
  So that I can concentrate on building awesome applications

  Scenario: Reading the tests
    Given I am in the test directory
    When I read the index.js file
    Then I should see "new Parser" somewhere

to a new Parser, and pipe it to a given destination.

var Parser = require('mocha-gherkin');
fs.createReadStream('local.feature')
  .pipe(new Parser)
  .pipe(process.stdout);

You'll get matching Mocha BDD style specs:

describe("Example feature", function() {

  describe("As a user of cucumber.js I want to have documentation on cucumber So that I can concentrate on building awesome applications", function() {

    describe("Reading the tests", function() {

      it("Given I am in the test directory", function() {

      });

      it("When I read the index.js file", function() {

      });

      it("Then I should see 'new Parser' somewhere", function() {

      });

    });

  });

});

Steps definition (kinda)

You can fill in the body of it() handlers with some kind of step definitions (definitely not valid cucumber step definitions.. but kind of)

var parser = new Parser({
  steps: fs.readFileSync('./steps.js', 'utf8')
});

The step.js file is a JavaScript file running in a new vm context, with Given, When, Then and And function available. Each one takes two argument, a regexp to match and a callback to read and use as a body function for mocha describe() and it().

Captured parameters are available as $1, $2 and so on, these placeholders get replaced by their relevant values from feature description.

Given(/I am in the "(.*)" directory/, function(done) {
  this.base = process.cwd();
  process.chdir(path.resolve('$1'));
  done();
});

When(/I read the "(.*)" file/, function(done) {
  this.file = fs.createReadStream('$1');
  this.file.pause();
  done();
});

And(/I pipe it through a "(.*)"/, function(done) {
  var self = this;
  this.output = '';
  this.parser = this.file.pipe($1)
    .on('data', function(c) { self.output += c })
    .on('close', done);

  this.file.resume();
});

Then(/I should see the content of "(.*)"/, function(done) {
  process.chdir(this.base);
  var output = this.output;
  fs.readFile('$1', 'utf8', function(err, body) {
    if(err) return done(err);
    assert.equal(body.trim(), output.trim());
    done();
  });
});