diff --git a/lib/pp.rb b/lib/pp.rb
index 6060282..e790f49 100644
--- a/lib/pp.rb
+++ b/lib/pp.rb
@@ -145,21 +145,13 @@ module PPMethods
     # Yields to a block
     # and preserves the previous set of objects being printed.
     def guard_inspect_key
-      if Thread.current[:__recursive_key__] == nil
-        Thread.current[:__recursive_key__] = {}.compare_by_identity
-      end
-
-      if Thread.current[:__recursive_key__][:inspect] == nil
-        Thread.current[:__recursive_key__][:inspect] = {}.compare_by_identity
-      end
-
-      save = Thread.current[:__recursive_key__][:inspect]
-
+      recursive_state = Thread.current[:__recursive_key__] ||= {}.compare_by_identity
+      save = recursive_state[:inspect] ||= {}.compare_by_identity
       begin
-        Thread.current[:__recursive_key__][:inspect] = {}.compare_by_identity
+        recursive_state[:inspect] = {}.compare_by_identity
         yield
       ensure
-        Thread.current[:__recursive_key__][:inspect] = save
+        recursive_state[:inspect] = save
       end
     end
 
@@ -167,9 +159,8 @@ def guard_inspect_key
     # to be pretty printed. Used to break cycles in chains of objects to be
     # pretty printed.
     def check_inspect_key(id)
-      Thread.current[:__recursive_key__] &&
-      Thread.current[:__recursive_key__][:inspect] &&
-      Thread.current[:__recursive_key__][:inspect].include?(id)
+      recursive_state = Thread.current[:__recursive_key__] or return false
+      recursive_state[:inspect]&.include?(id)
     end
 
     # Adds the object_id +id+ to the set of objects being pretty printed, so
@@ -186,7 +177,7 @@ def pop_inspect_key(id)
     private def guard_inspect(object)
       recursive_state = Thread.current[:__recursive_key__]
 
-      if recursive_state && recursive_state.key?(:inspect)
+      if recursive_state&.key?(:inspect)
         begin
           push_inspect_key(object)
           yield
@@ -322,12 +313,10 @@ def pp_hash(obj)
       # A pretty print for a pair of Hash
       def pp_hash_pair(k, v)
         if Symbol === k
-          sym_s = k.inspect
-          if sym_s[1].match?(/["$@!]/) || sym_s[-1].match?(/[%&*+\-\/<=>@\]^`|~]/)
-            text "#{k.to_s.inspect}:"
-          else
-            text "#{k}:"
+          if k.inspect.match?(%r[\A:["$@!]|[%&*+\-\/<=>@\]^`|~]\z])
+            k = k.to_s.inspect
           end
+          text "#{k}:"
         else
           pp k
           text ' '
diff --git a/test/test_pp.rb b/test/test_pp.rb
index c5340a3..4a273e6 100644
--- a/test/test_pp.rb
+++ b/test/test_pp.rb
@@ -257,7 +257,6 @@ def test_hash
   end
 
   def test_hash_symbol_colon_key
-    omit if RUBY_VERSION < "3.4."
     no_quote = "{a: 1, a!: 1, a?: 1}"
     unicode_quote = "{\u{3042}: 1}"
     quote0 = '{"": 1}'
@@ -270,12 +269,25 @@ def test_hash_symbol_colon_key
     assert_equal(quote1, PP.singleline_pp(eval(quote1), ''.dup))
     assert_equal(quote2, PP.singleline_pp(eval(quote2), ''.dup))
     assert_equal(quote3, PP.singleline_pp(eval(quote3), ''.dup))
-  end
+  end if RUBY_VERSION >= "3.4."
 
   def test_hash_in_array
     omit if RUBY_ENGINE == "jruby"
-    assert_equal("[{}]", PP.singleline_pp([->(*a){a.last.clear}.ruby2_keywords.call(a: 1)], ''.dup))
-    assert_equal("[{}]", PP.singleline_pp([Hash.ruby2_keywords_hash({})], ''.dup))
+    assert_equal("[{}]", passing_keywords {PP.singleline_pp([->(*a){a.last.clear}.ruby2_keywords.call(a: 1)], ''.dup)})
+    assert_equal("[{}]", passing_keywords {PP.singleline_pp([Hash.ruby2_keywords_hash({})], ''.dup)})
+  end
+
+  if RUBY_VERSION >= "3.0"
+    def passing_keywords(&_)
+      yield
+    end
+  else
+    def passing_keywords(&_)
+      verbose, $VERBOSE = $VERBOSE, nil
+      yield
+    ensure
+      $VERBOSE = verbose
+    end
   end
 
   def test_direct_pp