From ca2da262ef1dcbda19cb2830d3667c5797e0d9ee Mon Sep 17 00:00:00 2001
From: Koichi ITO <koic.ito@gmail.com>
Date: Thu, 22 Oct 2020 19:03:51 +0900
Subject: [PATCH] Make `SendNode#macro?` aware of struct constructor

This PR makes `SendNode#macro?` and `RuboCop::AST::Node#class_constructor?`
aware of struct constructor and `RuboCop::AST::Node#struct_constructor?`
is deprecated.

Like class constructor, struct constructor will be recognized as a
macro and will be awakened in the following `private` modifier:

```ruby
Foo = Struct.new(:foo) do
  private
    def private_foo
      foo
    end
end
```

With this change, this PR aims to resolve the following issue.
https://github.com/rubocop-hq/rubocop/issues/8919
---
 CHANGELOG.md                       |  4 ++++
 lib/rubocop/ast/node.rb            |  5 +++--
 spec/rubocop/ast/send_node_spec.rb | 11 +++++++++++
 3 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index fd295eb4f..da7a23935 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 ## master (unreleased)
 
+### Bug fixes
+
+* [#141](https://github.com/rubocop-hq/rubocop-ast/pull/141): Make `SendNode#macro?` and `RuboCop::AST::Node#class_constructor?` aware of struct constructor and `RuboCop::AST::Node#struct_constructor?` is deprecated. ([@koic][])
+
 ## 1.0.0 (2020-10-21)
 
 ### Changes
diff --git a/lib/rubocop/ast/node.rb b/lib/rubocop/ast/node.rb
index 996e84e8d..ac33f8848 100644
--- a/lib/rubocop/ast/node.rb
+++ b/lib/rubocop/ast/node.rb
@@ -484,10 +484,11 @@ def guard_clause?
       def_node_matcher :global_const?, '(const {nil? cbase} %1)'
 
       def_node_matcher :class_constructor?, <<~PATTERN
-        {       (send #global_const?({:Class :Module}) :new ...)
-         (block (send #global_const?({:Class :Module}) :new ...) ...)}
+        {       (send #global_const?({:Class :Module :Struct}) :new ...)
+         (block (send #global_const?({:Class :Module :Struct}) :new ...) ...)}
       PATTERN
 
+      # @deprecated Use `:class_constructor?`
       def_node_matcher :struct_constructor?, <<~PATTERN
         (block (send #global_const?(:Struct) :new ...) _ $_)
       PATTERN
diff --git a/spec/rubocop/ast/send_node_spec.rb b/spec/rubocop/ast/send_node_spec.rb
index b81d4b7a8..c8076e066 100644
--- a/spec/rubocop/ast/send_node_spec.rb
+++ b/spec/rubocop/ast/send_node_spec.rb
@@ -242,6 +242,17 @@ module Foo
         it { expect(send_node).to be_macro }
       end
 
+      context 'when parent is a struct constructor' do
+        let(:source) do
+          ['Foo = Struct.new do',
+           '>>bar :baz<<',
+           '  bar :qux',
+           'end'].join("\n")
+        end
+
+        it { expect(send_node).to be_macro }
+      end
+
       context 'when parent is a singleton class' do
         let(:source) do
           ['class << self',