diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index b71d424..77aed90 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -26,6 +26,7 @@ jobs:
         - { os: windows-latest, ruby: mingw }
         - { os: windows-latest, ruby: mswin }
         - { os: ubuntu-latest, ruby: 'jruby-head', bundle: 'bundle exec' }
+        - { os: ubuntu-latest, ruby: 'truffleruby-head' }
     runs-on: ${{ matrix.os }}
     steps:
     - uses: actions/checkout@v4
diff --git a/lib/pp.rb b/lib/pp.rb
index 1708dee..fb7aa7b 100644
--- a/lib/pp.rb
+++ b/lib/pp.rb
@@ -422,8 +422,10 @@ def pretty_print_cycle(q) # :nodoc:
 
 class Data # :nodoc:
   def pretty_print(q) # :nodoc:
-    q.group(1, sprintf("#<data %s", PP.mcall(self, Kernel, :class).name), '>') {
-      q.seplist(PP.mcall(self, Data, :members), lambda { q.text "," }) {|member|
+    class_name = PP.mcall(self, Kernel, :class).name
+    class_name = " #{class_name}" if class_name
+    q.group(1, "#<data#{class_name}", '>') {
+      q.seplist(PP.mcall(self, Kernel, :class).members, lambda { q.text "," }) {|member|
         q.breakable
         q.text member.to_s
         q.text '='
@@ -438,7 +440,7 @@ def pretty_print(q) # :nodoc:
   def pretty_print_cycle(q) # :nodoc:
     q.text sprintf("#<data %s:...>", PP.mcall(self, Kernel, :class).name)
   end
-end if "3.2" <= RUBY_VERSION
+end if defined?(Data.define)
 
 class Range # :nodoc:
   def pretty_print(q) # :nodoc:
diff --git a/test/test_pp.rb b/test/test_pp.rb
index bb2299a..473133b 100644
--- a/test/test_pp.rb
+++ b/test/test_pp.rb
@@ -140,15 +140,18 @@ def test_struct
     a = S.new(1,2)
     a.b = a
     assert_equal("#<struct Struct::S a=1, b=#<struct Struct::S:...>>\n", PP.pp(a, ''.dup))
-    assert_equal("#{a.inspect}\n", PP.pp(a, ''.dup))
+    assert_equal("#{a.inspect}\n", PP.pp(a, ''.dup)) unless RUBY_ENGINE == "truffleruby"
   end
 
-  if "3.2" <= RUBY_VERSION
+  if defined?(Data.define)
     D = Data.define(:aaa, :bbb)
     def test_data
       a = D.new("aaa", "bbb")
       assert_equal("#<data PPTestModule::PPCycleTest::D\n aaa=\"aaa\",\n bbb=\"bbb\">\n", PP.pp(a, ''.dup, 20))
       assert_equal("#{a.inspect}\n", PP.pp(a, ''.dup))
+
+      b = Data.define(:a).new(42)
+      assert_equal("#{b.inspect}\n", PP.pp(b, ''.dup))
     end
   end
 
@@ -164,7 +167,7 @@ def test_anonymous
   end
 
   def test_withinspect
-    omit if RUBY_ENGINE == "jruby"
+    omit if RUBY_ENGINE == "jruby" or RUBY_ENGINE == "truffleruby"
     a = []
     a << HasInspect.new(a)
     assert_equal("[<inspect:[...]>]\n", PP.pp(a, ''.dup))