Class: FeatureMap::Private::FeatureMetricsCalculator

Inherits:
Object
  • Object
show all
Defined in:
lib/feature_map/private/feature_metrics_calculator.rb

Constant Summary collapse

ABC_SIZE_METRIC = 
'abc_size'
CYCLOMATIC_COMPLEXITY_METRIC = 
'cyclomatic_complexity'
LINES_OF_CODE_METRIC = 
'lines_of_code'
TODO_LOCATIONS_METRIC = 
'todo_locations'
COMPLEXITY_RATIO_METRIC = 
'complexity_ratio'
ENCAPSULATION_RATIO_METRIC = 
'encapsulation_ratio'
SUPPORTED_METRICS = 
[
  ABC_SIZE_METRIC,
  CYCLOMATIC_COMPLEXITY_METRIC,
  LINES_OF_CODE_METRIC,
  TODO_LOCATIONS_METRIC,
  COMPLEXITY_RATIO_METRIC,
  ENCAPSULATION_RATIO_METRIC
].freeze

Class Method Summary collapse

Class Method Details

.calculate_for_feature(file_paths) ⇒ Object 



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# File 'lib/feature_map/private/feature_metrics_calculator.rb', line 23

def self.calculate_for_feature(file_paths)
  metrics = file_paths.map { |file| calculate_for_file(file) }

  # Handle numeric metrics
  aggregate_metrics = [ABC_SIZE_METRIC, CYCLOMATIC_COMPLEXITY_METRIC, LINES_OF_CODE_METRIC].each_with_object({}) do |metric_key, agg|
    agg[metric_key] = metrics.sum { |m| m[metric_key] || 0 }
  end

  # Handle additional supported metrics
  todo_locations = metrics.map { |m| m[TODO_LOCATIONS_METRIC] }.compact.reduce({}, :merge)
  aggregate_metrics[TODO_LOCATIONS_METRIC] = todo_locations
  aggregate_metrics[COMPLEXITY_RATIO_METRIC] = complexity_ratio(aggregate_metrics)
  aggregate_metrics[ENCAPSULATION_RATIO_METRIC] = encapsulation_ratio(file_paths, aggregate_metrics)

  aggregate_metrics
end

.calculate_for_file(file_path) ⇒ Object 



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# File 'lib/feature_map/private/feature_metrics_calculator.rb', line 40

def self.calculate_for_file(file_path)
  metrics = {
    LINES_OF_CODE_METRIC => LinesOfCodeCalculator.new(file_path).calculate,
    TODO_LOCATIONS_METRIC => TodoInspector.new(file_path).calculate

  }

  return metrics unless file_path.end_with?('.rb')

  # Lazy load the rubocop gem only when we need to process AST nodes to avoid introducing unnecessary
  # dependencies for use cases that do not exercise this functionality.
  require 'rubocop'

  file_content = File.read(file_path)
  source = RuboCop::ProcessedSource.new(file_content, RUBY_VERSION.to_f)
  return metrics unless source.ast

  # NOTE: We're using some internal RuboCop classes to calculate complexity metrics
  # for each file. Doing this tightly couples our functionality with RuboCop,
  # which does introduce some risk, should RuboCop decide to change the interface
  # of these classes. That being said, this is a tradeoff we're willing to
  # make right now.
  abc_calculator = RuboCop::Cop::Metrics::Utils::AbcSizeCalculator.new(source.ast)
  cyclomatic_calculator = CyclomaticComplexityCalculator.new(source.ast)

  metrics.merge(
    ABC_SIZE_METRIC => abc_calculator.calculate.first.round(2),
    CYCLOMATIC_COMPLEXITY_METRIC => cyclomatic_calculator.calculate
  )
end

.complexity_ratio(aggregate_metrics) ⇒ Object 



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# File 'lib/feature_map/private/feature_metrics_calculator.rb', line 71

def self.complexity_ratio(aggregate_metrics)
  return 0.0 if aggregate_metrics[LINES_OF_CODE_METRIC].nil? || aggregate_metrics[CYCLOMATIC_COMPLEXITY_METRIC].nil? || aggregate_metrics[CYCLOMATIC_COMPLEXITY_METRIC].zero?

  aggregate_metrics[LINES_OF_CODE_METRIC].to_f / aggregate_metrics[CYCLOMATIC_COMPLEXITY_METRIC]
end

.encapsulation_ratio(file_paths, aggregate_metrics) ⇒ Object 



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# File 'lib/feature_map/private/feature_metrics_calculator.rb', line 77

def self.encapsulation_ratio(file_paths, aggregate_metrics)
  return 0.0 if file_paths.nil? || aggregate_metrics[LINES_OF_CODE_METRIC].nil? || aggregate_metrics[LINES_OF_CODE_METRIC].zero?

  file_paths.length.to_f / aggregate_metrics[LINES_OF_CODE_METRIC]
end