Cucumber JSON "expanded" formatter (expands Scenario Outlines)

Cucumber_JSON_Expanded_Formatter_README.md

Cucumber JSON Expanded formatter

This is similar to the built-in Cucumber JSON formatter except it expands scenario outlines so each row is reported with its result. Thus, scenario outlines appear similar to regular scenarios in the JSON output.

This supports regular mode and "--expand" mode. In both cases, scenario outline tables are expanded (however the underlying logic for doing the expansion varies greatly).

This produces scenario outline JSON that cucumber-reporting can consume.

The expansion is quite a hack and may not be supported in all versions of Cucumber. Please monitor the following bug for a proper solution to scenario outlines in JSON: cucumber/gherkin#165

Notes:

• When not in "--expand" mode, duration can't be calculated per step. The duration for the entire feature is appended to the last step.
• Scenario Outlines are still called "Scenario Outlines" even though they look more like regular Scenarios in the output.
• Argument matches are empty.

Usage

Place the json_expanded_formatter.rb file in the features/support directory.

cucumber --format Cucumber::Formatter::JsonExpanded --out results.json features/

json_expanded_formatter.rb

#
# Copyright (c) 2014 Brandon Turner
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.

require 'cucumber/formatter/gherkin_formatter_adapter'
require 'cucumber/formatter/io'
require 'gherkin/formatter/json_formatter'

module Cucumber
  module Formatter
    ##
    # This is similar to the built-in Cucumber JSON formatter except it expands
    # scenario outlines so each row is reported with its result.  Thus, scenario
    # outlines appear similar to regular scenarios in the JSON output.
    #
    # This supports regular mode and "--expand" mode.  In both cases, scenario
    # outline tables are expanded (however the underlying logic for doing the
    # expansion varies greatly).
    #
    # This produces scenario outline JSON that
    # [cucumber-reporting](https://github.com/masterthought/cucumber-reporting)
    # can consume.
    #
    # The expansion is quite a hack and may not be supported in all versions of
    # Cucumber.  Please monitor the following bug for a proper solution to scenario
    # outlines in JSON:
    #   https://github.com/cucumber/gherkin/issues/165
    #
    # Notes:
    #   * When not in "--expand" mode, duration can't be calculated per step.
    #     The duration for the entire feature is appended to the last step.
    #   * Scenario Outlines are still called "Scenario Outlines" even though
    #     they look more like regular Scenarios in the output.
    #   * Argument matches are empty.
    class JsonExpanded < GherkinFormatterAdapter
      include Io

      def initialize(runtime, io, options)
        @io = ensure_io(io, "json")
        if Gem.loaded_specs['cucumber'].version >= Gem::Version.new('1.3.17')
          super(Gherkin::Formatter::JSONFormatter.new(@io), false, options)
        else
          super(Gherkin::Formatter::JSONFormatter.new(@io), false)
        end
      end

      def before_feature_element(feature_element)
        @outline_table = nil
        if feature_element.is_a?(Ast::ScenarioOutline)
          @outline = true
          @feature_element = feature_element
        else
          super
        end
      end

      def before_step(step)
        if @outline_table
          table_row = @outline_table.example_rows[@outline_table_row]
          outline_before_step(step, table_row)
        elsif !@outline
          super
        end
      end

      def before_step_result(keyword, step_match, multiline_arg, status, exception, source_indent, background, file_colon_line)
        if @outline_table
          outline_before_step_result(status, exception)
        elsif !@outline
          super
        end
      end

      def before_examples(examples)
        unless @outline
          super
        end
      end

      def after_step(*args)
        if !@outline || @outline_table
          super
        end
      end

      def before_outline_table(outline_table)
        @outline_table = outline_table
        @outline_table_row = -1
      end

      def after_outline_table(outline_table)
        @outline_table = nil
      end

      def scenario_name(*args)
        if @outline_table
          # Scenario Name is the only way we know we are moving
          # to a new table row in "--expand" mode.
          @outline_table_row += 1
          outline_before_table_row(@feature_element)
        end
      end

      def before_table_row(table_row)
        @table_row_time = Time.now
      end

      ##
      # Output a Scenario Outline element for each table row.  In JSON
      # this appears more like a scenario than a scenario outline.
      # This is only called when not in "--expand" mode.
      def after_table_row(table_row)
        # XXX: Hack to get step collection
        step_invocations = table_row.instance_variable_get('@step_invocations')

        if step_invocations
          # Add a new "scenario" for this row
          outline_before_table_row(@feature_element)

          step_invocations.each do |step|
            outline_before_step(step, table_row)
            outline_before_step_result(step.status, step.exception)
          end

          # We don't have enough hooks to get duration for each step, so
          # just report the total duration at the end of the execution
          step_finish = (Time.now - @table_row_time)
          @gf.append_duration(step_finish)
        end
      end

      private

      def outline_before_step(step, table_row)
        @gf.step(step_from_table(step, table_row))

        # TODO: We don't actually populate the match.arguments array.
        # Should we try to emulate a step_match?
        # We don't want to use outline_args as we've replaced the
        # placeholders with actual values.
        match = Gherkin::Formatter::Model::Match.new([], nil)
        @gf.match(match)

        @step_time = Time.now
      end

      def outline_before_step_result(status, exception)
        error_message = exception ? "#{exception.message} (#{exception.class})\n#{exception.backtrace.join("\n")}" : nil
        @gf.result(Gherkin::Formatter::Model::Result.new(status, nil, error_message))
      end

      def outline_before_table_row(feature_element)
        @gf.scenario_outline(feature_element.gherkin_statement)
      end

      # Replaces table cells in the name of the given step.
      #
      # @return Gherkin::Formatter::Model::Step with
      def step_from_table(step, table_row)
        # XXX: Hack to change the name from:
        #   "Given two numbers <number_1> and <number_2>"
        # to:
        #   "Given two number 1 and 2"
        # We actually instantiate a separate Gherkin::Formatter::Model::Step
        # to avoid corrupting the original step.
        name = step.gherkin_statement.name.dup
        table_row.to_hash.each do |key, val|
          name.gsub!("<#{key}>", val)
        end
        Gherkin::Formatter::Model::Step.new(
          step.gherkin_statement.comments,
          step.gherkin_statement.keyword,
          name,
          step.gherkin_statement.line,
          step.gherkin_statement.rows,
          step.gherkin_statement.doc_string
        )
      end
    end
  end
end

We're in the process of converting this formatter to a gem here — https://github.com/rapid7/cucumber-json_expanded We've been using it internally at @rapid7 but haven't yet published the gem. cc: @lsanchez-r7

What is the status of your gem conversion?

@enkessler On our major projects we've completed the move to cucumber 2.0.x. Not sure we'll be publishing the conversion, but feel free to fork this code and publish a gem yourself!