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Class: RuboCop::Cop::VariableForce::Variable Private

Relationships & Source Files
Inherits: Object
Defined in: lib/rubocop/cop/variable_force/variable.rb

Overview

A Variable represents existence of a local variable. This holds a variable declaration node and some states of the variable.

Constant Summary

Class Method Summary

Instance Attribute Summary

Instance Method Summary

Constructor Details

.new(name, declaration_node, scope) ⇒ Variable

[ GitHub ] 

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 15



def initialize(name, declaration_node, scope)
  unless VARIABLE_DECLARATION_TYPES.include?(declaration_node.type)
    raise ArgumentError,
          "Node type must be any of #{VARIABLE_DECLARATION_TYPES}, " \
          "passed #{declaration_node.type}"
  end

  @name = name.to_sym
  @declaration_node = declaration_node
  @scope = scope

  @assignments = []
  @references = []
  @captured_by_block = false
end


  







Instance Attribute Details



  

    #argument?  ⇒ Boolean  (readonly)
  



  

    
  





  


  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 105



def argument?
  ARGUMENT_DECLARATION_TYPES.include?(@declaration_node.type)
end


  








  

    #assignments   (readonly)
  

  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 11



attr_reader :name, :declaration_node, :scope, :assignments, :references, :captured_by_block


  








  

    #block_argument?  ⇒ Boolean  (readonly)
  



  

    
  





  


  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 113



def block_argument?
  argument? && @scope.node.block_type?
end


  








  

    #captured_by_block?   (readonly)
  



  

    


Alias for #captured_by_block.



  



  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 13



alias captured_by_block? captured_by_block


  








  

    #declaration_node   (readonly)
  

  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 11



attr_reader :name, :declaration_node, :scope, :assignments, :references, :captured_by_block


  








  

    #explicit_block_local_variable?  ⇒ Boolean  (readonly)
  



  

    
  





  


  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 121



def explicit_block_local_variable?
  @declaration_node.shadowarg_type?
end


  








  

    #keyword_argument?  ⇒ Boolean  (readonly)
  



  

    
  





  


  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 117



def keyword_argument?
  %i[kwarg kwoptarg].include?(@declaration_node.type)
end


  








  

    #method_argument?  ⇒ Boolean  (readonly)
  



  

    
  





  


  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 109



def method_argument?
  argument? && %i[def defs].include?(@scope.node.type)
end


  








  

    #name   (readonly)
  

  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 11



attr_reader :name, :declaration_node, :scope, :assignments, :references, :captured_by_block


  








  

    #referenced?  ⇒ Boolean  (readonly)
  



  

    
  





  


  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 46



def referenced?
  !@references.empty?
end


  








  

    #references   (readonly)
  

  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 11



attr_reader :name, :declaration_node, :scope, :assignments, :references, :captured_by_block


  








  

    #scope   (readonly)
  

  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 11



attr_reader :name, :declaration_node, :scope, :assignments, :references, :captured_by_block


  








  

    #should_be_unused?  ⇒ Boolean  (readonly)
  



  

    
  





  


  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 101



def should_be_unused?
  name.to_s.start_with?('_')
end


  








  

    #used?  ⇒ Boolean  (readonly)
  



  

    


This is a convenient way to check whether the variable is used
in its entire variable lifetime.
For more precise usage check, refer Assignment#used?.






Once the variable is captured by a block, we have no idea
when, where, and how many times the block would be invoked.
This means we cannot track the usage of the variable.
So we consider it’s used to suppress false positive offenses.



  





  


  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 97



def used?
  @captured_by_block || referenced?
end


  







Instance Method Details



  

    #assign(node)  
  

  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 31



def assign(node)
  assignment = Assignment.new(node, self)

  mark_last_as_reassigned!(assignment)

  @assignments << assignment
end


  








  

    #capture_with_block!  
  

  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 85



def capture_with_block!
  @captured_by_block = true
end


  








  

    #captured_by_block   (readonly)
    Also known as: #captured_by_block?
  

  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 11



attr_reader :name, :declaration_node, :scope, :assignments, :references, :captured_by_block


  








  

    #in_modifier_conditional?(assignment)  ⇒ Boolean 
  



  

    


Metrics/CyclomaticComplexity, Metrics/PerceivedComplexity



  





  


  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 77



def in_modifier_conditional?(assignment)
  parent = assignment.node.parent
  parent = parent.parent if parent&.begin_type?
  return false if parent.nil?

  parent.type?(:if, :while, :until) && parent.modifier_form?
end


  








  

    #mark_last_as_reassigned!(assignment)  
  

  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 39



def mark_last_as_reassigned!(assignment)
  return if captured_by_block?
  return unless assignment.branch == @assignments.last&.branch

  @assignments.last&.reassigned!
end


  








  

    #reference!(node)  
  



  

    


Metrics/CyclomaticComplexity, Metrics/PerceivedComplexity



  





  


  [ GitHub ]


  

  


# File 'lib/rubocop/cop/variable_force/variable.rb', line 51



def reference!(node)
  reference = Reference.new(node, @scope)
  @references << reference
  consumed_branches = nil

  @assignments.reverse_each do |assignment|
    next if consumed_branches&.include?(assignment.branch)

    assignment.reference!(node) unless assignment.run_exclusively_with?(reference)

    # Modifier if/unless conditions are special. Assignments made in
    # them do not put the assigned variable in scope to the left of the
    # if/unless keyword. A preceding assignment is needed to put the
    # variable in scope. For this reason we skip to the next assignment
    # here.
    next if in_modifier_conditional?(assignment)

    break if !assignment.branch || assignment.branch == reference.branch

    unless assignment.branch.may_run_incompletely?
      (consumed_branches ||= Set.new) << assignment.branch
    end
  end
end