Class: RuboCop::Cop::Style::ParallelAssignment::AssignmentSorter

Inherits:
Object
  • Object
show all
Extended by:
Macros
Includes:
TSort
Defined in:
lib/rubocop/cop/style/parallel_assignment.rb

Overview

Helper class necessitated by silly design of TSort prior to Ruby 2.1 Newer versions have a better API, but that doesn't help us

Instance Method Summary collapse

Constructor Details

#initialize(assignments) ⇒ AssignmentSorter

Returns a new instance of AssignmentSorter.


132
133
134
# File 'lib/rubocop/cop/style/parallel_assignment.rb', line 132

def initialize(assignments)
  @assignments = assignments
end

Instance Method Details

#accesses?(rhs, lhs) ⇒ Boolean

`lhs` is an assignment method call like `obj.attr=` or `ary=`. Does `rhs` access the same value which is assigned by `lhs`?

Returns:

  • (Boolean)

161
162
163
164
165
166
167
168
169
170
171
# File 'lib/rubocop/cop/style/parallel_assignment.rb', line 161

def accesses?(rhs, lhs)
  if lhs.method?(:[]=)
    # FIXME: Workaround `rubocop:disable` comment for JRuby.
    # rubocop:disable Performance/RedundantEqualityComparisonBlock
    matching_calls(rhs, lhs.receiver, :[]).any? { |args| args == lhs.arguments }
    # rubocop:enable Performance/RedundantEqualityComparisonBlock
  else
    access_method = lhs.method_name.to_s.chop.to_sym
    matching_calls(rhs, lhs.receiver, access_method).any?
  end
end

#dependency?(lhs, rhs) ⇒ Boolean

Returns:

  • (Boolean)

154
155
156
157
# File 'lib/rubocop/cop/style/parallel_assignment.rb', line 154

def dependency?(lhs, rhs)
  uses_var?(rhs, var_name(lhs)) ||
    (lhs.send_type? && lhs.assignment_method? && accesses?(rhs, lhs))
end

#matching_calls(node, receiver, method_name) ⇒ Object


130
# File 'lib/rubocop/cop/style/parallel_assignment.rb', line 130

def_node_search :matching_calls, '(send %1 %2 $...)'

#tsort_each_child(assignment) ⇒ Object


140
141
142
143
144
145
146
147
148
149
150
151
152
# File 'lib/rubocop/cop/style/parallel_assignment.rb', line 140

def tsort_each_child(assignment)
  # yield all the assignments which must come after `assignment`
  # (due to dependencies on the previous value of the assigned var)
  my_lhs, _my_rhs = *assignment

  @assignments.each do |other|
    _other_lhs, other_rhs = *other

    next unless dependency?(my_lhs, other_rhs)

    yield other
  end
end

#tsort_each_node(&block) ⇒ Object


136
137
138
# File 'lib/rubocop/cop/style/parallel_assignment.rb', line 136

def tsort_each_node(&block)
  @assignments.each(&block)
end

#uses_var?(node) ⇒ Object


127
# File 'lib/rubocop/cop/style/parallel_assignment.rb', line 127

def_node_search :uses_var?, '{({lvar ivar cvar gvar} %) (const _ %)}'

#var_name(node) ⇒ Object


124
# File 'lib/rubocop/cop/style/parallel_assignment.rb', line 124

def_node_matcher :var_name, '{(casgn _ $_) (_ $_)}'