Add RuntimeMacros module

RuntimeMacros `.def_node_matcher` and `.def_node_search` accept block
that will be evaluated within cop context to get pattern pattern.
It can be used to pattern match values from config because are available
only during runtime.

lib/rubocop-rspec.rb

@@ -12,6 +12,7 @@
 require_relative 'rubocop/rspec/top_level_describe'
 require_relative 'rubocop/rspec/wording'
 require_relative 'rubocop/rspec/language'
+require_relative 'rubocop/rspec/language/runtime_macros'
 require_relative 'rubocop/rspec/language/node_pattern'
 require_relative 'rubocop/rspec/top_level_group'
 require_relative 'rubocop/rspec/concept'

lib/rubocop/cop/rspec/cop.rb

@@ -20,6 +20,7 @@ module RSpec
       class Cop < ::RuboCop::Cop::Cop
         include RuboCop::RSpec::Language
         include RuboCop::RSpec::Language::NodePattern
+        extend RuboCop::RSpec::Language::RuntimeMacros
 
         DEFAULT_CONFIGURATION =
           RuboCop::RSpec::CONFIG.fetch('AllCops').fetch('RSpec')

lib/rubocop/rspec/language/node_pattern.rb

@@ -6,6 +6,7 @@ module Language
       # Common node matchers used for matching against the rspec DSL
       module NodePattern
         extend RuboCop::NodePattern::Macros
+        extend RuntimeMacros
 
         def_node_matcher :example_group?, ExampleGroups::ALL.block_pattern
         def_node_matcher :shared_group?, SharedGroups::ALL.block_pattern

lib/rubocop/rspec/language/runtime_macros.rb

@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+module RuboCop
+  module RSpec
+    module Language
+      # RuntimeMacros `.def_node_matcher` and `.def_node_search` accept block
+      # that will be evaluated within cop context to get pattern pattern.
+      # It can be used to pattern match values from config because are available
+      # only during runtime.
+      module RuntimeMacros
+        def def_runtime_node_matcher(method_name, &pattern_block)
+          define_method method_name do |node, *args, &block|
+            pattern = RuboCop::NodePattern.new(instance_eval(&pattern_block))
+            match = pattern.match(node, *args, &block)
+
+            method_name.to_s.end_with?('?') ? !match.nil? : match
+          end
+        end
+
+        def def_runtime_node_search(method_name, &pattern_block)
+          define_method method_name do |node, *args, &block|
+            pattern = RuboCop::NodePattern.new(instance_eval(&pattern_block))
+            search_method = method_name.to_s.end_with?('?') ? :any? : :select
+
+            node.each_node.public_method(search_method)
+              .call(&pattern.public_method(:match, *args, &block))
+          end
+        end
+      end
+    end
+  end
+end