From 99234f6e7b4ab4b8aabc3d20cfaa2b111fd9653e Mon Sep 17 00:00:00 2001
From: Jonathan del Strother <me@delstrother.com>
Date: Fri, 23 Aug 2024 10:32:49 +0100
Subject: [PATCH] Micro-optimization to AmazingPrint::ActiveRecord#cast
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I kept seeing Module#ancestors show up in some profiling involving SemanticLogger.

Changing to `foo.is_a?(ActiveRecord::Relation)` and `foo <= ActiveRecord::Base` should be equivalent, but makes `AmazingPrint::Inspector#awesome` 7% faster:

```ruby
require "rails"
require "active_record"
require "amazing_print"
require "benchmark/ips"

inspector = AmazingPrint::Inspector.new
log = { foo: { bar: ["baz"] } }
Benchmark.ips do |x|
  x.report("ancestors.include?") do |times|
    i = 0
    $ap_ancestors = true
    while i < times
      inspector.awesome(log)
      i += 1
    end
  end
  x.report("class <= ") do |times|
    i = 0
    $ap_ancestors = false
    while i < times
      inspector.awesome(log)
      i += 1
    end
  end

  x.compare!
end
```

```
ruby 3.2.4 (2024-04-23 revision af471c0e01) [arm64-darwin23]
Warming up --------------------------------------
  ancestors.include?     4.081k i/100ms
           class <=      4.289k i/100ms
Calculating -------------------------------------
  ancestors.include?     40.419k (± 1.5%) i/s -    204.050k in   5.049537s
           class <=      43.345k (± 1.5%) i/s -    218.739k in   5.047616s

Comparison:
           class <= :    43344.7 i/s
  ancestors.include?:    40418.6 i/s - 1.07x  slower
```
---
 lib/amazing_print/ext/active_record.rb | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/amazing_print/ext/active_record.rb b/lib/amazing_print/ext/active_record.rb
index 082a187..67762b5 100644
--- a/lib/amazing_print/ext/active_record.rb
+++ b/lib/amazing_print/ext/active_record.rb
@@ -22,9 +22,9 @@ def cast_with_active_record(object, type)
         cast = :active_record_instance
       elsif object.is_a?(::ActiveModel::Errors)
         cast = :active_model_error
-      elsif object.is_a?(Class) && object.ancestors.include?(::ActiveRecord::Base)
+      elsif object.is_a?(Class) && object <= ::ActiveRecord::Base
         cast = :active_record_class
-      elsif type == :activerecord_relation || object.class.ancestors.include?(::ActiveRecord::Relation)
+      elsif type == :activerecord_relation || object.is_a?(::ActiveRecord::Relation)
         cast = :array
       end
       cast