lib/rubocop/cop/lint/ambiguous_regexp_literal.rb
# frozen_string_literal: true
module RuboCop
module Cop
module Lint
# Checks for ambiguous regexp literals in the first argument of
# a method invocation without parentheses.
#
# @example
#
# # bad
#
# # This is interpreted as a method invocation with a regexp literal,
# # but it could possibly be `/` method invocations.
# # (i.e. `do_something./(pattern)./(i)`)
# do_something /pattern/i
#
# @example
#
# # good
#
# # With parentheses, there's no ambiguity.
# do_something(/pattern/i)
class AmbiguousRegexpLiteral < Base
extend AutoCorrector
MSG = 'Ambiguous regexp literal. Parenthesize the method arguments ' \
"if it's surely a regexp literal, or add a whitespace to the " \
'right of the `/` if it should be a division.'
def on_new_investigation
processed_source.diagnostics.each do |diagnostic|
if target_ruby_version >= 3.0
next unless diagnostic.reason == :ambiguous_regexp
else
next unless diagnostic.reason == :ambiguous_literal
end
offense_node = find_offense_node_by(diagnostic)
add_offense(diagnostic.location, severity: diagnostic.level) do |corrector|
add_parentheses(offense_node, corrector)
end
end
end
private
def find_offense_node_by(diagnostic)
node = processed_source.ast.each_node(:regexp).find do |regexp_node|
regexp_node.source_range.begin_pos == diagnostic.location.begin_pos
end
find_offense_node(node.parent, node)
end
def find_offense_node(node, regexp_receiver)
return node if first_argument_is_regexp?(node) || !node.parent
if (node.parent.send_type? && node.receiver) ||
method_chain_to_regexp_receiver?(node, regexp_receiver)
node = find_offense_node(node.parent, regexp_receiver)
end
node
end
def first_argument_is_regexp?(node)
node.send_type? && node.first_argument&.regexp_type?
end
def method_chain_to_regexp_receiver?(node, regexp_receiver)
return false unless (parent = node.parent)
return false unless (parent_receiver = parent.receiver)
parent.parent && parent_receiver.receiver == regexp_receiver
end
end
end
end
end