Have SendNode#def_modifier? return the def node it modifies, or `…

…nil` instead of boolean

Stricter check (used to check any child, including the receiver of the `send`)

changelog/change_have_sendnodedef_modifier_return_the_def.md

@@ -0,0 +1 @@
+* [#x](https://github.com/rubocop-hq/rubocop-ast/pull/x): Have `SendNode#def_modifier?` return the `def` node it modifies, or `nil` instead of boolean. ([@marcandre][])

lib/rubocop/ast/node/mixin/method_dispatch_node.rb

@@ -165,15 +165,21 @@ def arithmetic_operation?
         ARITHMETIC_OPERATORS.include?(method_name)
       end
 
-      # Checks if this node is part of a chain of `def` modifiers.
+      # @!method def_modifier?(node = self)
+      # Checks if this node is part of a chain of `def` or `defs` modifiers.
       #
       # @example
       #
       #   private def foo; end
       #
-      # @return [Boolean] whether the dispatched method is a `def` modifier
-      def def_modifier?
-        adjacent_def_modifier? || each_child_node(:send).any?(&:def_modifier?)
+      # @return [Node | nil] returns the `def|defs` node this is a modifier for,
+      # or `nil` if it isn't a def modifier
+      def def_modifier?(node=self)
+        if node.send_type? && node.receiver.nil?
+          arg = node.children[2]
+          return arg if arg.def_type? || arg.defs_type?
+          def_modifier?(arg)
+        end
       end
 
       # Checks whether this is a lambda. Some versions of parser parses

spec/rubocop/ast/send_node_spec.rb

@@ -1106,19 +1106,19 @@ def bar
     context 'with a prefixed def modifier' do
       let(:source) { 'foo def bar; end' }
 
-      it { expect(send_node).to be_def_modifier }
+      it { expect(send_node.def_modifier?.method_name).to eq(:bar) }
     end
 
     context 'with several prefixed def modifiers' do
       let(:source) { 'foo bar baz def qux; end' }
 
-      it { expect(send_node).to be_def_modifier }
+      it { expect(send_node.def_modifier?.method_name).to eq(:qux) }
     end
 
     context 'with a block containing a method definition' do
       let(:source) { 'foo bar { baz def qux; end }' }
 
-      it { expect(send_node).not_to be_def_modifier }
+      it { expect(send_node.def_modifier?).to be_nil }
     end
   end