diff --git a/lib/yarp/ripper_compat.rb b/lib/yarp/ripper_compat.rb
index f29f7a1bf1..c76f3fd07a 100644
--- a/lib/yarp/ripper_compat.rb
+++ b/lib/yarp/ripper_compat.rb
@@ -47,9 +47,9 @@ module YARP
       Ripper::PARSER_EVENT_TABLE.each do |event, arity|
         case event
         when /_new\z/
-          alias :"on_#{event}" :_dispatch_event_new if arity == 0
+          alias_method :"on_#{event}", :_dispatch_event_new if arity == 0
         when /_add\z/
-          alias :"on_#{event}" :_dispatch_event_push
+          alias_method :"on_#{event}", :_dispatch_event_push
         end
       end
     end
@@ -168,7 +168,7 @@ module YARP
     def _dispatch7(_, _, _, _, _, _, _); end
 
     (Ripper::SCANNER_EVENT_TABLE.merge(Ripper::PARSER_EVENT_TABLE)).each do |event, arity|
-      alias :"on_#{event}" :"_dispatch#{arity}"
+      alias_method :"on_#{event}", :"_dispatch#{arity}"
     end
   end
 end
diff --git a/test/yarp/comments_test.rb b/test/yarp/comments_test.rb
index e22dffd46d..5c49f7b86e 100644
--- a/test/yarp/comments_test.rb
+++ b/test/yarp/comments_test.rb
@@ -52,7 +52,7 @@ class CommentsTest < Test::Unit::TestCase
   def assert_comment(source, type, location)
     result = YARP.parse(source)
     assert result.errors.empty?, result.errors.map(&:message).join("\n")
-    result => YARP::ParseResult[comments: [YARP::Comment[type: type]]]
+    assert_equal result.comments.first.type, type
     assert_equal result.comments.first.location.start_offset, location.begin
     assert_equal result.comments.first.location.end_offset, location.end
   end
diff --git a/test/yarp/errors_test.rb b/test/yarp/errors_test.rb
index 0777efe47a..e89ade0ba5 100644
--- a/test/yarp/errors_test.rb
+++ b/test/yarp/errors_test.rb
@@ -1097,10 +1097,11 @@ class ErrorsTest < Test::Unit::TestCase
   private
 
   def assert_errors(expected, source, errors)
-    assert_nil Ripper.sexp_raw(source)
+    # Ripper behaves differently on JRuby/TruffleRuby, so only check this on CRuby
+    assert_nil Ripper.sexp_raw(source) if RUBY_ENGINE == "ruby"
 
     result = YARP.parse(source)
-    result => YARP::ParseResult[value: YARP::ProgramNode[statements: YARP::StatementsNode[body: [*, node]]]]
+    node = result.value.statements.body.last
 
     assert_equal_nodes(expected, node, compare_location: false)
     assert_equal(errors, result.errors.map { |e| [e.message, e.location.start_offset..e.location.end_offset] })
@@ -1113,7 +1114,6 @@ class ErrorsTest < Test::Unit::TestCase
   end
 
   def expression(source)
-    YARP.parse(source) => YARP::ParseResult[value: YARP::ProgramNode[statements: YARP::StatementsNode[body: [*, node]]]]
-    node
+    YARP.parse(source).value.statements.body.last
   end
 end
diff --git a/test/yarp/location_test.rb b/test/yarp/location_test.rb
index 2f551949e5..2aaaa7aa76 100644
--- a/test/yarp/location_test.rb
+++ b/test/yarp/location_test.rb
@@ -753,9 +753,11 @@ module YARP
     private
 
     def assert_location(kind, source, expected = 0...source.length)
-      YARP.parse(source) => ParseResult[comments: [], errors: [], value: node]
+      result = YARP.parse(source)
+      assert_equal [], result.comments
+      assert_equal [], result.errors
 
-      node => ProgramNode[statements: [*, node]]
+      node = result.value.statements.body.last
       node = yield node if block_given?
 
       assert_kind_of kind, node
diff --git a/test/yarp/parse_test.rb b/test/yarp/parse_test.rb
index 91752cd483..43a1deb8fb 100644
--- a/test/yarp/parse_test.rb
+++ b/test/yarp/parse_test.rb
@@ -23,7 +23,8 @@ class ParseTest < Test::Unit::TestCase
   end
 
   def test_empty_string
-    YARP.parse("") => YARP::ParseResult[value: YARP::ProgramNode[statements: YARP::StatementsNode[body: []]]]
+    result = YARP.parse("")
+    assert_equal [], result.value.statements.body
   end
 
   known_failures = %w[
@@ -107,7 +108,9 @@ class ParseTest < Test::Unit::TestCase
 
       # Finally, assert that we can lex the source and get the same tokens as
       # Ripper.
-      YARP.lex_compat(source) => { errors: [], value: tokens }
+      lex_result = YARP.lex_compat(source)
+      assert_equal [], lex_result.errors
+      tokens = lex_result.value
 
       begin
         YARP.lex_ripper(source).zip(tokens).each do |(ripper, yarp)|