From 226bbc74e8a0245866462fe9593b5411c3dd4c59 Mon Sep 17 00:00:00 2001
From: Kevin Abel <kevin.abel.0@gmail.com>
Date: Sat, 9 Jan 2021 15:11:30 -0600
Subject: [PATCH] utils/ast: Loose the check for Formula class node

Allows single class files with side-effects that load other classes that inherit `Formula`.
---
 Library/Homebrew/utils/ast.rb | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/Library/Homebrew/utils/ast.rb b/Library/Homebrew/utils/ast.rb
index 5c2bed0446..1343ce10d4 100644
--- a/Library/Homebrew/utils/ast.rb
+++ b/Library/Homebrew/utils/ast.rb
@@ -138,10 +138,14 @@ module Utils
       def process_formula(formula_contents)
         processed_source, root_node = process_source(formula_contents)
 
-        class_node = if root_node.class_type?
-          root_node
-        elsif root_node.begin_type?
-          root_node.children.find { |n| n.class_type? && n.parent_class&.const_name == "Formula" }
+        class_node = root_node if root_node.class_type?
+        if root_node.begin_type?
+          nodes = root_node.children.select(&:class_type?)
+          class_node = if nodes.count > 1
+            nodes.find { |n| n.parent_class&.const_name == "Formula" }
+          else
+            nodes.first
+          end
         end
 
         raise "Could not find formula class!" if class_node.nil?