Fix an error for Capybara/RSpec/HaveSelector when passing no arguments

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 - Add `Capybara/AmbiguousClick` cop and make soft-deprecated `Capybara/ClickLinkOrButtonStyle` cop. If you want to use `EnforcedStyle: strict`, use `Capybara/AmbiguousClick` cop instead. ([@ydah])
 - Add new `Capybara/FindAllFirst` cop. ([@ydah])
+- Fix an error for `Capybara/RSpec/HaveSelector` when passing no arguments. ([@earlopain])
 
 ## 2.21.0 (2024-06-08)
 
@@ -78,6 +79,7 @@
 [@aried3r]: https://github.com/aried3r
 [@bquorning]: https://github.com/bquorning
 [@darhazer]: https://github.com/Darhazer
+[@earlopain]: https://github.com/earlopain
 [@onumis]: https://github.com/onumis
 [@oskarsezerins]: https://github.com/OskarsEzerins
 [@pirj]: https://github.com/pirj

lib/rubocop/cop/capybara/rspec/have_selector.rb

@@ -42,7 +42,8 @@ class HaveSelector < ::RuboCop::Cop::Base
           SELECTORS = %i[css xpath].freeze
 
           def on_send(node)
-            argument = node.first_argument
+            return unless (argument = node.first_argument)
+
             on_select_with_type(node, argument) if argument.sym_type?
             on_select_without_type(node) if %i[str dstr].include?(argument.type)
           end

spec/rubocop/cop/capybara/rspec/have_selector_spec.rb

@@ -75,6 +75,12 @@
     RUBY
   end
 
+  it 'registers no offense when no arguments are passed' do
+    expect_no_offenses(<<~RUBY)
+      expect(foo).to have_selector
+    RUBY
+  end
+
   context 'when DefaultSelector is xpath' do
     let(:default_selector) { 'xpath' }