Class: RuboCop::Cop::Style::OneLineConditional

Inherits:
Cop
  • Object
show all
Includes:
OnNormalIfUnless
Defined in:
lib/rubocop/cop/style/one_line_conditional.rb

Overview

TODO: Make configurable. Checks for uses of if/then/else/end on a single line.

Constant Summary collapse

MSG = 
'Favor the ternary operator (`?:`) ' \
'over `%s/then/else/end` constructs.'.freeze

Constants included from Util

Util::ASGN_NODES, Util::BYTE_ORDER_MARK, Util::CONDITIONAL_NODES, Util::EQUALS_ASGN_NODES, Util::LITERAL_REGEX, Util::LOGICAL_OPERATOR_NODES, Util::MODIFIER_NODES, Util::OPERATOR_METHODS, Util::SHORTHAND_ASGN_NODES

Instance Attribute Summary

Attributes inherited from Cop

#config, #corrections, #offenses, #processed_source

Instance Method Summary collapse

Methods included from OnNormalIfUnless

#on_if

Methods inherited from Cop

#add_offense, all, badge, #config_to_allow_offenses, #config_to_allow_offenses=, #cop_config, #cop_name, cop_name, #correct, department, #duplicate_location?, #excluded_file?, #find_location, #highlights, inherited, #initialize, #join_force?, lint?, match?, #message, #messages, non_rails, #parse, qualified_cop_name, #relevant_file?, #target_ruby_version

Methods included from AST::Sexp

#s

Methods included from NodePattern::Macros

#def_node_matcher, #def_node_search, #node_search, #node_search_all, #node_search_body, #node_search_first

Methods included from AutocorrectLogic

#autocorrect?, #autocorrect_enabled?, #autocorrect_requested?, #support_autocorrect?

Methods included from IgnoredNode

#ignore_node, #ignored_node?, #part_of_ignored_node?

Methods included from Util

begins_its_line?, block_length, comment_line?, compatible_external_encoding_for?, directions, double_quotes_acceptable?, double_quotes_required?, effective_column, ends_its_line?, escape_string, first_part_of_call_chain, hard_to_type?, interpret_string_escapes, line_distance, line_range, move_pos, needs_escaping?, numeric_range_size, on_node, operator?, parentheses?, parenthesized_call?, preceed?, range_between, range_with_surrounding_comma, range_with_surrounding_space, same_line?, source_range, strip_quotes, stripped_source_upto, to_string_literal, to_supported_styles, to_symbol_literal, within_node?

Methods included from PathUtil

absolute?, match_path?, relative_path

Constructor Details

This class inherits a constructor from RuboCop::Cop::Cop

Instance Method Details

#autocorrect(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/one_line_conditional.rb', line 20

def autocorrect(node)
  lambda do |corrector|
    corrector.replace(node.source_range, replacement(node))
  end
end

#expr_replacement(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/one_line_conditional.rb', line 46

def expr_replacement(node)
  requires_parentheses?(node) ? "(#{node.source})" : node.source
end

#keyword_with_changed_precedence?(node) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rubocop/cop/style/one_line_conditional.rb', line 66

def keyword_with_changed_precedence?(node)
  return false unless node.keyword?
  return true if node.keyword_not?

  !parenthesized_call?(node)
end

#method_call_with_changed_precedence?(node) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rubocop/cop/style/one_line_conditional.rb', line 58

def method_call_with_changed_precedence?(node)
  return false unless node.send_type?
  return false if node.method_args.empty?
  return false if parenthesized_call?(node)

  !operator?(node.method_name)
end

#on_normal_if_unless(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/one_line_conditional.rb', line 14

def on_normal_if_unless(node)
  return unless node.single_line? && node.else_branch

  add_offense(node, :expression, format(MSG, node.keyword))
end

#replacement(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/one_line_conditional.rb', line 26

def replacement(node)
  return to_ternary(node) unless node.parent

  if [:and, :or].include?(node.parent.type)
    return "(#{to_ternary(node)})"
  end

  if node.parent.send_type? && operator?(node.parent.method_name)
    return "(#{to_ternary(node)})"
  end

  to_ternary(node)
end

#requires_parentheses?(node) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rubocop/cop/style/one_line_conditional.rb', line 50

def requires_parentheses?(node)
  return true if [:and, :or, :if].include?(node.type)
  return true if node.assignment?
  return true if method_call_with_changed_precedence?(node)

  keyword_with_changed_precedence?(node)
end

#to_ternary(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/one_line_conditional.rb', line 40

def to_ternary(node)
  cond, body, else_clause = *node
  "#{expr_replacement(cond)} ? #{expr_replacement(body)} : " \
    "#{expr_replacement(else_clause)}"
end