From 76dc82808dc6daab7247aaacb5faec0f76c397b9 Mon Sep 17 00:00:00 2001
From: Nobuyoshi Nakada <nobu@ruby-lang.org>
Date: Fri, 28 Aug 2026 02:43:24 +0300
Subject: [PATCH 1/2] Respect custom Delegator printers from upstream PR 60

Source-only backport of 30113562abd53b4689ef20288a13bdc3fef5577d; tests excluded under consumer task policy.
---
 lib/pp.rb | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/lib/pp.rb b/lib/pp.rb
index 798a4f4..2768ca0 100644
--- a/lib/pp.rb
+++ b/lib/pp.rb
@@ -200,14 +200,17 @@ def pop_inspect_key(id)
     def pp(obj)
       # If obj is a Delegator then use the object being delegated to for cycle
       # detection
-      obj = obj.__getobj__ if defined?(::Delegator) and ::Delegator === obj
+      delegated = defined?(::Delegator) && ::Delegator === obj
+      key = delegated ? obj.__getobj__ : obj
 
-      if check_inspect_key(obj)
+      if check_inspect_key(key)
+        obj = key if delegated and !obj.respond_to?(:pretty_print_cycle)
         group {obj.pretty_print_cycle self}
         return
       end
 
-      guard_inspect(obj) do
+      guard_inspect(key) do
+        obj = key if delegated and !obj.respond_to?(:pretty_print)
         group do
           obj.pretty_print self
         rescue NoMethodError

From 5695f43cde17f2cfc27c732879b74ce5cec40753 Mon Sep 17 00:00:00 2001
From: Oskar Eichler <oskar@songstats.com>
Date: Mon, 31 Aug 2026 01:58:39 +0300
Subject: [PATCH 2/2] Preserve custom inspect on Delegator wrappers

---
 lib/pp.rb       | 25 +++++++++++++++++++++----
 test/test_pp.rb | 47 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 68 insertions(+), 4 deletions(-)

diff --git a/lib/pp.rb b/lib/pp.rb
index 2768ca0..32f4c9f 100644
--- a/lib/pp.rb
+++ b/lib/pp.rb
@@ -210,11 +210,28 @@ def pp(obj)
       end
 
       guard_inspect(key) do
-        obj = key if delegated and !obj.respond_to?(:pretty_print)
+        custom_inspect = false
+        if delegated
+          delegator_class = obj.class
+          unless delegator_class.public_method_defined?(:pretty_print)
+            singleton_methods = obj.singleton_methods(false)
+            custom_inspect =
+              !singleton_methods.include?(:pretty_print) &&
+              (delegator_class.public_method_defined?(:inspect) ||
+               singleton_methods.include?(:inspect))
+          end
+        end
+        obj = key if delegated && !custom_inspect && !obj.respond_to?(:pretty_print)
         group do
-          obj.pretty_print self
-        rescue NoMethodError
-          text Kernel.instance_method(:inspect).bind_call(obj)
+          if custom_inspect
+            text obj.inspect
+          else
+            begin
+              obj.pretty_print self
+            rescue NoMethodError
+              text Kernel.instance_method(:inspect).bind_call(obj)
+            end
+          end
         end
       end
     end
diff --git a/test/test_pp.rb b/test/test_pp.rb
index 922ed37..56c32a1 100644
--- a/test/test_pp.rb
+++ b/test/test_pp.rb
@@ -312,6 +312,24 @@ def test_direct_pp
 class PPDelegateTest < Test::Unit::TestCase
   class A < DelegateClass(Array); end
 
+  class Delegated < SimpleDelegator
+    def pretty_print(q)
+      q.text "<delegated>"
+    end
+  end
+
+  class Inspected < SimpleDelegator
+    def inspect
+      "<delegated inspect>"
+    end
+  end
+
+  class RaisingInspect < SimpleDelegator
+    def inspect
+      self.missing_from_inspect
+    end
+  end
+
   def test_delegate
     assert_equal("[]\n", A.new([]).pretty_inspect, "[ruby-core:25804]")
   end
@@ -327,6 +345,35 @@ def test_delegate_cycle
 
     assert_equal(cycle_pretty_inspect, delegator_cycle_pretty_inspect)
   end
+
+  def test_delegate_pretty_print
+    delegated = Delegated.new(HasPrettyPrint.new(nil))
+    assert_equal("<delegated>\n", PP.pp(delegated, ''.dup))
+  end
+
+  def test_delegate_inspect
+    delegated = Inspected.new(HasInspect.new(:target))
+    assert_equal("<delegated inspect>\n", PP.pp(delegated, ''.dup))
+  end
+
+  def test_delegate_singleton_inspect
+    delegated = SimpleDelegator.new(HasInspect.new(:target))
+    def delegated.inspect() "<delegated inspect>" end
+
+    assert_equal("<delegated inspect>\n", PP.pp(delegated, ''.dup))
+  end
+
+  def test_delegate_inspect_error
+    error = assert_raise(NoMethodError) do
+      PP.pp(RaisingInspect.new(HasInspect.new(:target)), ''.dup)
+    end
+    assert_equal(:missing_from_inspect, error.name)
+  end
+
+  def test_delegate_basic_object
+    delegated = SimpleDelegator.new(BasicObject.new)
+    assert_match(/\A#<BasicObject:0x[\da-f]+>\n\z/, PP.pp(delegated, ''.dup))
+  end
 end
 
 class PPFileStatTest < Test::Unit::TestCase