From c51668d24962602b781a7348451de807f74b05be Mon Sep 17 00:00:00 2001
From: Nobuyoshi Nakada <nobu@ruby-lang.org>
Date: Fri, 24 Jan 2025 15:51:28 +0900
Subject: [PATCH] Add `Test::Unit::CoreAssertions#assert_raise_kind_of`

Similar to `Test::Unit::assert_raise`, but allows sub classes too.
---
 tool/lib/core_assertions.rb          | 37 ++++++++++++++++++++++++++++
 tool/test/testunit/test_assertion.rb | 12 +++++++++
 2 files changed, 49 insertions(+)

diff --git a/tool/lib/core_assertions.rb b/tool/lib/core_assertions.rb
index 62ada2bdca0628..66822b4e3bc206 100644
--- a/tool/lib/core_assertions.rb
+++ b/tool/lib/core_assertions.rb
@@ -514,6 +514,43 @@ def assert_raise_with_message(exception, expected, msg = nil, &block)
         ex
       end
 
+      # :call-seq:
+      #   assert_raise_kind_of(*args, &block)
+      #
+      #Tests if the given block raises one of the given exceptions or
+      #sub exceptions of the given exceptions.  If the last argument
+      #is a String, it will be used as the error message.
+      #
+      #    assert_raise do #Fails, no Exceptions are raised
+      #    end
+      #
+      #    assert_raise SystemCallErr do
+      #      Dir.chdir(__FILE__) #Raises Errno::ENOTDIR, so assertion succeeds
+      #    end
+      def assert_raise_kind_of(*exp, &b)
+        case exp.last
+        when String, Proc
+          msg = exp.pop
+        end
+
+        begin
+          yield
+        rescue Test::Unit::PendedError => e
+          raise e unless exp.include? Test::Unit::PendedError
+        rescue *exp => e
+          pass
+        rescue Exception => e
+          flunk(message(msg) {"#{mu_pp(exp)} family exception expected, not #{mu_pp(e)}"})
+        ensure
+          unless e
+            exp = exp.first if exp.size == 1
+
+            flunk(message(msg) {"#{mu_pp(exp)} family expected but nothing was raised"})
+          end
+        end
+        e
+      end
+
       TEST_DIR = File.join(__dir__, "test/unit") #:nodoc:
 
       # :call-seq:
diff --git a/tool/test/testunit/test_assertion.rb b/tool/test/testunit/test_assertion.rb
index 76f3418bc4ffa5..b0c2267b31ade3 100644
--- a/tool/test/testunit/test_assertion.rb
+++ b/tool/test/testunit/test_assertion.rb
@@ -47,6 +47,18 @@ def test_assert_raise_with_message
     end
   end
 
+  def test_assert_raise_kind_of
+    my_error = Class.new(StandardError)
+
+    assert_raise_kind_of(my_error) do
+      raise my_error
+    end
+
+    assert_raise_kind_of(StandardError) do
+      raise my_error
+    end
+  end
+
   def test_assert_pattern_list
     assert_pattern_list([/foo?/], "foo")
     assert_not_pattern_list([/foo?/], "afoo")