An error occurs in Rails/SelectMap when select receiver is implicit

[elektronaut]

The error occurs when using select/map with an implicit receiver, i.e inside a model.

class Model < ApplicationRecord
  class << self
    def labels
      select("label").map(&:label)
    end
  end
end

Expected behavior

It should have been corrected to:

def labels
  pluck(:label)
end

Actual behavior

An NoMethodError is raised.

An error occurred while Rails/SelectMap cop was inspecting [rails app]/app/models/model.rb:4:6.
undefined method `begin' for nil:NilClass
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-rails-2.21.1/lib/rubocop/cop/rails/select_map.rb:55:in `autocorrect'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-rails-2.21.1/lib/rubocop/cop/rails/select_map.rb:40:in `block in on_send'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cop/base.rb:377:in `correct'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cop/base.rb:181:in `add_offense'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-rails-2.21.1/lib/rubocop/cop/rails/select_map.rb:39:in `on_send'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cop/commissioner.rb:143:in `public_send'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cop/commissioner.rb:143:in `block (2 levels) in trigger_restricted_cops'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cop/commissioner.rb:171:in `with_cop_error_handling'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cop/commissioner.rb:142:in `block in trigger_restricted_cops'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cop/commissioner.rb:141:in `each'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cop/commissioner.rb:141:in `trigger_restricted_cops'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cop/commissioner.rb:70:in `on_send'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-ast-1.29.0/lib/rubocop/ast/traversal.rb:154:in `on_def'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cop/commissioner.rb:71:in `on_def'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-ast-1.29.0/lib/rubocop/ast/traversal.rb:137:in `block in on_dstr'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-ast-1.29.0/lib/rubocop/ast/traversal.rb:137:in `each'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-ast-1.29.0/lib/rubocop/ast/traversal.rb:137:in `on_dstr'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cop/commissioner.rb:71:in `on_begin'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-ast-1.29.0/lib/rubocop/ast/traversal.rb:154:in `on_class'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cop/commissioner.rb:71:in `on_class'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-ast-1.29.0/lib/rubocop/ast/traversal.rb:20:in `walk'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cop/commissioner.rb:87:in `investigate'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cop/team.rb:156:in `investigate_partial'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cop/team.rb:98:in `investigate'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/runner.rb:345:in `block in inspect_file'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/runner.rb:344:in `each'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/runner.rb:344:in `flat_map'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/runner.rb:344:in `inspect_file'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/runner.rb:287:in `block in do_inspection_loop'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/runner.rb:321:in `block in iterate_until_no_changes'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/runner.rb:314:in `loop'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/runner.rb:314:in `iterate_until_no_changes'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/runner.rb:283:in `do_inspection_loop'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/runner.rb:164:in `block in file_offenses'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/runner.rb:189:in `file_offense_cache'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/runner.rb:163:in `file_offenses'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/runner.rb:154:in `process_file'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/runner.rb:135:in `block in each_inspected_file'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/runner.rb:134:in `each'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/runner.rb:134:in `reduce'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/runner.rb:134:in `each_inspected_file'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/runner.rb:120:in `inspect_files'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/runner.rb:73:in `run'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cli/command/execute_runner.rb:26:in `block in execute_runner'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cli/command/execute_runner.rb:52:in `with_redirect'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cli/command/execute_runner.rb:25:in `execute_runner'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cli/command/execute_runner.rb:17:in `run'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cli/command.rb:11:in `run'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cli/environment.rb:18:in `run'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cli.rb:118:in `run_command'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cli.rb:125:in `execute_runners'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cli.rb:51:in `block in run'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cli.rb:77:in `profile_if_needed'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/lib/rubocop/cli.rb:43:in `run'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/exe/rubocop:19:in `block in <top (required)>'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/3.2.0/benchmark.rb:311:in `realtime'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/rubocop-1.56.3/exe/rubocop:19:in `<top (required)>'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/bin/rubocop:25:in `load'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/bin/rubocop:25:in `<top (required)>'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/3.2.0/bundler/cli/exec.rb:58:in `load'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/3.2.0/bundler/cli/exec.rb:58:in `kernel_load'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/3.2.0/bundler/cli/exec.rb:23:in `run'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/3.2.0/bundler/cli.rb:492:in `exec'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/3.2.0/bundler/vendor/thor/lib/thor/command.rb:27:in `run'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/3.2.0/bundler/vendor/thor/lib/thor/invocation.rb:127:in `invoke_command'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/3.2.0/bundler/vendor/thor/lib/thor.rb:392:in `dispatch'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/3.2.0/bundler/cli.rb:34:in `dispatch'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/3.2.0/bundler/vendor/thor/lib/thor/base.rb:485:in `start'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/3.2.0/bundler/cli.rb:28:in `start'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/bundler-2.4.10/libexec/bundle:45:in `block in <top (required)>'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/3.2.0/bundler/friendly_errors.rb:117:in `with_friendly_errors'
/Users/inge/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/bundler-2.4.10/libexec/bundle:33:in `<top (required)>'
/Users/inge/.rbenv/versions/3.2.2/bin/bundle:25:in `load'
/Users/inge/.rbenv/versions/3.2.2/bin/bundle:25:in `<main>'

Steps to reproduce the problem

The following test case triggers the error:

it 'registers an offense when used with an implicit target' do
  expect_offense(<<~RUBY)
    select('column_name').map(&:column_name)
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Use `pluck(:column_name)` instead of `select` with `map`.
  RUBY

  expect_correction(<<~RUBY)
    pluck(:column_name)
  RUBY
end

RuboCop version

$ rubocop -V
1.56.3 (using Parser 3.2.2.3, rubocop-ast 1.29.0, running on ruby 3.2.2) [arm64-darwin22]
  - rubocop-rails 2.21.1
  - rubocop-rspec 2.24.0