Class: RuboCop::Cop::Style::ConditionalAssignment

Inherits:

Cop

• Object
• Cop
• RuboCop::Cop::Style::ConditionalAssignment

Includes:

ConfigurableEnforcedStyle, IgnoredNode, ConditionalAssignmentHelper

Defined in:

lib/rubocop/cop/style/conditional_assignment.rb

Overview

Check for ‘if` and `case` statements where each branch is used for assignment to the same variable when using the return of the condition can be used instead.

Examples:

EnforcedStyle: assign_to_condition

# bad
if foo
  bar = 1
else
  bar = 2
end

case foo
when 'a'
  bar += 1
else
  bar += 2
end

if foo
  some_method
  bar = 1
else
  some_other_method
  bar = 2
end

# good
bar = if foo
        1
      else
        2
      end

bar += case foo
       when 'a'
         1
       else
         2
       end

bar << if foo
         some_method
         1
       else
         some_other_method
         2
       end

EnforcedStyle: assign_inside_condition
# bad
bar = if foo
        1
      else
        2
      end

bar += case foo
       when 'a'
         1
       else
         2
       end

bar << if foo
         some_method
         1
       else
         some_other_method
         2
       end

# good
if foo
  bar = 1
else
  bar = 2
end

case foo
when 'a'
  bar += 1
else
  bar += 2
end

if foo
  some_method
  bar = 1
else
  some_other_method
  bar = 2
end

Constant Summary

MSG =

'Use the return of the conditional for variable assignment ' \
'and comparison.'.freeze

ASSIGN_TO_CONDITION_MSG =

'Assign variables inside of conditionals'.freeze

VARIABLE_ASSIGNMENT_TYPES =

[:casgn, :cvasgn, :gvasgn, :ivasgn, :lvasgn].freeze

ASSIGNMENT_TYPES =

VARIABLE_ASSIGNMENT_TYPES +
[:and_asgn, :or_asgn, :op_asgn, :masgn].freeze

LINE_LENGTH =

'Metrics/LineLength'.freeze

INDENTATION_WIDTH =

'Style/IndentationWidth'.freeze

ENABLED =

'Enabled'.freeze

MAX =

'Max'.freeze

SINGLE_LINE_CONDITIONS_ONLY =

'SingleLineConditionsOnly'.freeze

WIDTH =

'Width'.freeze

METHODS =

[:[]=, :<<, :=~, :!~, :<=>].freeze

CONDITION_TYPES =

[:if, :case].freeze

Constants included from ConditionalAssignmentHelper

RuboCop::Cop::Style::ConditionalAssignmentHelper::ALIGN_WITH, RuboCop::Cop::Style::ConditionalAssignmentHelper::END_ALIGNMENT, RuboCop::Cop::Style::ConditionalAssignmentHelper::EQUAL, RuboCop::Cop::Style::ConditionalAssignmentHelper::KEYWORD

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

• #on_case(node) ⇒ Object
• #on_if(node) ⇒ Object
• #on_send(node) ⇒ Object

Methods included from IgnoredNode

#ignore_node, #ignored_node?, #part_of_ignored_node?

Methods included from ConfigurableEnforcedStyle

#alternative_style, #alternative_styles, #ambiguous_style_detected, #correct_style_detected, #detected_style, #detected_style=, #no_acceptable_style!, #no_acceptable_style?, #opposite_style_detected, #style, #style_detected, #style_parameter_name, #supported_styles, #unexpected_style_detected

Methods included from ConditionalAssignmentHelper

#expand_elses, #expand_when_branches, #indent, #lhs, #tail

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 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

#on_case(node) ⇒ Object

# File 'lib/rubocop/cop/style/conditional_assignment.rb', line 252

def on_case(node)
  return unless style == :assign_to_condition
  return unless node.else_branch

  when_branches = expand_when_branches(node.when_branches)
  branches = [*when_branches, node.else_branch]

  check_node(node, branches)
end

#on_if(node) ⇒ Object

# File 'lib/rubocop/cop/style/conditional_assignment.rb', line 238

def on_if(node)
  return unless style == :assign_to_condition
  return if node.elsif?

  else_branch = node.else_branch
  elsif_branches, else_branch = expand_elses(else_branch)

  return unless else_branch

  branches = [node.if_branch, *elsif_branches, else_branch]

  check_node(node, branches)
end

#on_send(node) ⇒ Object

# File 'lib/rubocop/cop/style/conditional_assignment.rb', line 230

def on_send(node)
  return unless assignment_type?(node)
  return unless style == :assign_inside_condition
  return unless assignment_rhs_exist?(node)

  check_assignment_to_condition(node)
end