1 files changed, 43 insertions, 0 deletions
diff --git a/spec/ruby/core/exception/detailed_message_spec.rb b/spec/ruby/core/exception/detailed_message_spec.rb
new file mode 100644
index 0000000000..fbe4443daa
--- /dev/null
+++ b/spec/ruby/core/exception/detailed_message_spec.rb
@@ -0,0 +1,43 @@
+require_relative '../../spec_helper'
+require_relative 'fixtures/common'
+
+describe "Exception#detailed_message" do
+  ruby_version_is "3.2" do
+    it "returns decorated message" do
+      RuntimeError.new("new error").detailed_message.should == "new error (RuntimeError)"
+    end
+
+    it "is called by #full_message to allow message customization" do
+      exception = Exception.new("new error")
+      def exception.detailed_message(**)
+        "<prefix>#{message}<suffix>"
+      end
+      exception.full_message(highlight: false).should.include? "<prefix>new error<suffix>"
+    end
+
+    it "accepts highlight keyword argument and adds escape control sequences" do
+      RuntimeError.new("new error").detailed_message(highlight: true).should == "\e[1mnew error (\e[1;4mRuntimeError\e[m\e[1m)\e[m"
+    end
+
+    it "allows and ignores other keyword arguments" do
+      RuntimeError.new("new error").detailed_message(foo: true).should == "new error (RuntimeError)"
+    end
+
+    it "returns just a message if exception class is anonymous" do
+      Class.new(RuntimeError).new("message").detailed_message.should == "message"
+    end
+
+    it "returns 'unhandled exception' for an instance of RuntimeError with empty message" do
+      RuntimeError.new("").detailed_message.should == "unhandled exception"
+    end
+
+    it "returns just class name for an instance of RuntimeError subclass with empty message" do
+      DetailedMessageSpec::C.new("").detailed_message.should == "DetailedMessageSpec::C"
+    end
+
+    it "returns a generated class name for an instance of RuntimeError anonymous subclass with empty message" do
+      klass = Class.new(RuntimeError)
+      klass.new("").detailed_message.should =~ /\A#<Class:0x\h+>\z/
+    end
+  end
+end