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::EQUALS_ASGN_NODES, Util::LITERAL_REGEX, Util::OPERATOR_METHODS, Util::SHORTHAND_ASGN_NODES, Util::STRING_ESCAPES, Util::STRING_ESCAPE_REGEX

Instance Attribute Summary

Attributes inherited from Cop

#config, #corrections, #offenses, #processed_source

Instance Method Summary collapse

Methods included from OnNormalIfUnless

#case_else_clause, #if_else_clause, #invoke_hook_for_normal_if_unless, #on_if

Methods included from IfNode

#elsif?, #if_else?, #if_node_parts, #modifier_if?, #ternary?

Methods inherited from Cop

#add_offense, all, #config_to_allow_offenses, #config_to_allow_offenses=, #cop_config, cop_name, #cop_name, cop_type, #correct, #debug?, #details, #display_cop_names?, #display_style_guide?, #excluded_file?, #extra_details?, inherited, #initialize, #join_force?, lint?, match?, #message, non_rails, #parse, qualified_cop_name, #reference_url, #relevant_file?, #style_guide_url, #target_ruby_version

Methods included from Sexp

#s

Methods included from NodePattern::Macros

#def_node_matcher, #def_node_search, #node_search_body

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?, directions, double_quotes_acceptable?, double_quotes_required?, effective_column, ends_its_line?, first_part_of_call_chain, interpret_string_escapes, line_range, move_pos, numeric_range_size, on_node, operator?, parentheses?, parenthesized_call?, range_with_surrounding_comma, range_with_surrounding_space, source_range, strip_quotes, to_string_literal, 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 24

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 47

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 67

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 59

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 15

def on_normal_if_unless(node)
  exp = node.source
  return if exp.include?("\n")
  return unless node.loc.respond_to?(:else) && node.loc.else
  condition = exp.include?('if') ? 'if' : 'unless'

  add_offense(node, :expression, format(MSG, condition))
end

#replacement(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/one_line_conditional.rb', line 30

def replacement(node)
  return ternary(node) unless node.parent
  return "(#{ternary(node)})" if [:and, :or].include?(node.parent.type)

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

  ternary(node)
end

#requires_parentheses?(node) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rubocop/cop/style/one_line_conditional.rb', line 51

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

#ternary(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/one_line_conditional.rb', line 41

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