From abcf9d390e99257d4a7282e1120006f19a8b5c3a Mon Sep 17 00:00:00 2001
From: Koichi ITO <koic.ito@gmail.com>
Date: Mon, 11 Oct 2021 23:15:33 +0900
Subject: [PATCH] [Fix #10180] Fix an error for `Style/SelectByRegexp`

Fixes #10180.

This PR fixes an error for `Style/SelectByRegexp` when using `match?` without a receiver.
---
 changelog/fix_an_error_for_style_select_by_regexp.md | 1 +
 lib/rubocop/cop/style/select_by_regexp.rb            | 5 +++++
 spec/rubocop/cop/style/select_by_regexp_spec.rb      | 6 ++++++
 3 files changed, 12 insertions(+)
 create mode 100644 changelog/fix_an_error_for_style_select_by_regexp.md

diff --git a/changelog/fix_an_error_for_style_select_by_regexp.md b/changelog/fix_an_error_for_style_select_by_regexp.md
new file mode 100644
index 00000000000..f6dfd943f9f
--- /dev/null
+++ b/changelog/fix_an_error_for_style_select_by_regexp.md
@@ -0,0 +1 @@
+* [#10180](https://github.com/rubocop/rubocop/issues/10180): Fix an error for `Style/SelectByRegexp` when using `match?` without a receiver. ([@koic][])
diff --git a/lib/rubocop/cop/style/select_by_regexp.rb b/lib/rubocop/cop/style/select_by_regexp.rb
index 50489dfb371..52887ce635a 100644
--- a/lib/rubocop/cop/style/select_by_regexp.rb
+++ b/lib/rubocop/cop/style/select_by_regexp.rb
@@ -83,6 +83,7 @@ def on_send(node)
           return if block_node.body.begin_type?
           return if receiver_allowed?(block_node.receiver)
           return unless (regexp_method_send_node = extract_send_node(block_node))
+          return if match_predicate_without_receiver?(regexp_method_send_node)
 
           regexp = find_regexp(regexp_method_send_node)
           register_offense(node, block_node, regexp)
@@ -127,6 +128,10 @@ def find_regexp(node)
             node.receiver
           end
         end
+
+        def match_predicate_without_receiver?(node)
+          node.send_type? && node.method?(:match?) && node.receiver.nil?
+        end
       end
     end
   end
diff --git a/spec/rubocop/cop/style/select_by_regexp_spec.rb b/spec/rubocop/cop/style/select_by_regexp_spec.rb
index b3a2b51e98b..4c942ef3a46 100644
--- a/spec/rubocop/cop/style/select_by_regexp_spec.rb
+++ b/spec/rubocop/cop/style/select_by_regexp_spec.rb
@@ -279,6 +279,12 @@
             array.#{method} { /regexp/.match?(foo(_1)) }
           RUBY
         end
+
+        it 'does not register an offense when using `match?` without a receiver' do
+          expect_no_offenses(<<~RUBY)
+            array.#{method} { |item| match?(item) }
+          RUBY
+        end
       end
     end
   end