16 files changed, 354 insertions, 28 deletions
diff --git a/test/ruby/namespace/instance_variables.rb b/test/ruby/namespace/instance_variables.rb
new file mode 100644
index 0000000000..1562ad5d45
--- /dev/null
+++ b/test/ruby/namespace/instance_variables.rb
@@ -0,0 +1,21 @@
+class String
+  class << self
+    attr_reader :str_ivar1
+
+    def str_ivar2
+      @str_ivar2
+    end
+  end
+
+  @str_ivar1 = 111
+  @str_ivar2 = 222
+end
+
+class StringDelegator < BasicObject
+private
+  def method_missing(...)
+    ::String.public_send(...)
+  end
+end
+
+StringDelegatorObj = StringDelegator.new
diff --git a/test/ruby/test_ast.rb b/test/ruby/test_ast.rb
index 72a0d821a0..d22823470b 100644
--- a/test/ruby/test_ast.rb
+++ b/test/ruby/test_ast.rb
@@ -1397,6 +1397,24 @@ dummy
       assert_locations(node.children[-1].locations, [[1, 0, 1, 16], [1, 0, 1, 5], [1, 8, 1, 9], [1, 13, 1, 16]])
     end
 
+    def test_colon2_locations
+      node = ast_parse("A::B")
+      assert_locations(node.children[-1].locations, [[1, 0, 1, 4], [1, 1, 1, 3], [1, 3, 1, 4]])
+
+      node = ast_parse("A::B::C")
+      assert_locations(node.children[-1].locations, [[1, 0, 1, 7], [1, 4, 1, 6], [1, 6, 1, 7]])
+      assert_locations(node.children[-1].children[0].locations, [[1, 0, 1, 4], [1, 1, 1, 3], [1, 3, 1, 4]])
+    end
+
+    def test_colon3_locations
+      node = ast_parse("::A")
+      assert_locations(node.children[-1].locations, [[1, 0, 1, 3], [1, 0, 1, 2], [1, 2, 1, 3]])
+
+      node = ast_parse("::A::B")
+      assert_locations(node.children[-1].locations, [[1, 0, 1, 6], [1, 3, 1, 5], [1, 5, 1, 6]])
+      assert_locations(node.children[-1].children[0].locations, [[1, 0, 1, 3], [1, 0, 1, 2], [1, 2, 1, 3]])
+    end
+
     def test_dot2_locations
       node = ast_parse("1..2")
       assert_locations(node.children[-1].locations, [[1, 0, 1, 4], [1, 1, 1, 3]])
diff --git a/test/ruby/test_backtrace.rb b/test/ruby/test_backtrace.rb
index fca7b62030..01a757f827 100644
--- a/test/ruby/test_backtrace.rb
+++ b/test/ruby/test_backtrace.rb
@@ -454,4 +454,10 @@ class TestBacktrace < Test::Unit::TestCase
     foo::Bar.baz
     end;
   end
+
+  def test_backtrace_internal_frame
+    backtrace = tap { break caller_locations(0) }
+    assert_equal(__FILE__, backtrace[1].path) # not "<internal:kernel>"
+    assert_equal("Kernel#tap", backtrace[1].label)
+  end
 end
diff --git a/test/ruby/test_compile_prism.rb b/test/ruby/test_compile_prism.rb
index 819d0d35aa..86f7f0b14f 100644
--- a/test/ruby/test_compile_prism.rb
+++ b/test/ruby/test_compile_prism.rb
@@ -1053,6 +1053,9 @@ module Prism
       assert_prism_eval("for foo, in  [1,2,3] do end")
 
       assert_prism_eval("for i, j in {a: 'b'} do; i; j; end")
+
+      # Test splat node as index in for loop
+      assert_prism_eval("for *x in [[1,2], [3,4]] do; x; end")
     end
 
     ############################################################################
diff --git a/test/ruby/test_data.rb b/test/ruby/test_data.rb
index bb38f8ec91..dd698fdcc4 100644
--- a/test/ruby/test_data.rb
+++ b/test/ruby/test_data.rb
@@ -280,4 +280,10 @@ class TestData < Test::Unit::TestCase
     assert_not_same(test, loaded)
     assert_predicate(loaded, :frozen?)
   end
+
+  def test_frozen_subclass
+    test = Class.new(Data.define(:a)).freeze.new(a: 0)
+    assert_kind_of(Data, test)
+    assert_equal([:a], test.members)
+  end
 end
diff --git a/test/ruby/test_encoding.rb b/test/ruby/test_encoding.rb
index ee37199be0..0ab357f53a 100644
--- a/test/ruby/test_encoding.rb
+++ b/test/ruby/test_encoding.rb
@@ -33,7 +33,7 @@ class TestEncoding < Test::Unit::TestCase
     encodings.each do |e|
       assert_raise(TypeError) { e.dup }
       assert_raise(TypeError) { e.clone }
-      assert_equal(e.object_id, Marshal.load(Marshal.dump(e)).object_id)
+      assert_same(e, Marshal.load(Marshal.dump(e)))
     end
   end
 
diff --git a/test/ruby/test_gc.rb b/test/ruby/test_gc.rb
index daa645b349..3516cefedf 100644
--- a/test/ruby/test_gc.rb
+++ b/test/ruby/test_gc.rb
@@ -393,12 +393,10 @@ class TestGc < Test::Unit::TestCase
 
       # Create some objects and place it in a WeakMap
       wmap = ObjectSpace::WeakMap.new
-      ary = Array.new(count)
-      enum = count.times
-      enum.each.with_index do |i|
+      ary = Array.new(count) do |i|
         obj = Object.new
-        ary[i] = obj
         wmap[obj] = nil
+        obj
       end
 
       # Run full GC to collect stats about weak references
@@ -421,7 +419,7 @@ class TestGc < Test::Unit::TestCase
       GC.start
 
       # Sometimes the WeakMap has a few elements, which might be held on by registers.
-      assert_operator(wmap.size, :<=, 2)
+      assert_operator(wmap.size, :<=, count / 1000)
 
       assert_operator(GC.latest_gc_info(:weak_references_count), :<=, before_weak_references_count - count + error_tolerance)
       assert_operator(GC.latest_gc_info(:retained_weak_references_count), :<=, before_retained_weak_references_count - count + error_tolerance)
diff --git a/test/ruby/test_io_buffer.rb b/test/ruby/test_io_buffer.rb
index 55296c1f23..62c4667888 100644
--- a/test/ruby/test_io_buffer.rb
+++ b/test/ruby/test_io_buffer.rb
@@ -121,6 +121,16 @@ class TestIOBuffer < Test::Unit::TestCase
     end
   end
 
+  def test_string_mapped_buffer_frozen
+    string = "Hello World".freeze
+    IO::Buffer.for(string) do |buffer|
+      assert_raise IO::Buffer::AccessError, "Buffer is not writable!" do
+        buffer.set_string("abc")
+      end
+      assert_equal "H".ord, buffer.get_value(:U8, 0)
+    end
+  end
+
   def test_non_string
     not_string = Object.new
 
@@ -683,4 +693,17 @@ class TestIOBuffer < Test::Unit::TestCase
     buf.set_string('a', 0, 0)
     assert_predicate buf, :empty?
   end
+
+  # https://bugs.ruby-lang.org/issues/21210
+  def test_bug_21210
+    omit "compaction is not supported on this platform" unless GC.respond_to?(:compact)
+
+    str = +"hello"
+    buf = IO::Buffer.for(str)
+    assert_predicate buf, :valid?
+
+    GC.verify_compaction_references(expand_heap: true, toward: :empty)
+
+    assert_predicate buf, :valid?
+  end
 end
diff --git a/test/ruby/test_namespace.rb b/test/ruby/test_namespace.rb
index 395f244c8e..f13063be48 100644
--- a/test/ruby/test_namespace.rb
+++ b/test/ruby/test_namespace.rb
@@ -222,6 +222,26 @@ class TestNamespace < Test::Unit::TestCase
     end;
   end
 
+  def test_instance_variable
+    pend unless Namespace.enabled?
+
+    @n.require_relative('namespace/instance_variables')
+
+    assert_equal [], String.instance_variables
+    assert_equal [:@str_ivar1, :@str_ivar2], @n::StringDelegatorObj.instance_variables
+    assert_equal 111, @n::StringDelegatorObj.str_ivar1
+    assert_equal 222, @n::StringDelegatorObj.str_ivar2
+    assert_equal 222, @n::StringDelegatorObj.instance_variable_get(:@str_ivar2)
+
+    @n::StringDelegatorObj.instance_variable_set(:@str_ivar3, 333)
+    assert_equal 333, @n::StringDelegatorObj.instance_variable_get(:@str_ivar3)
+    @n::StringDelegatorObj.remove_instance_variable(:@str_ivar1)
+    assert_nil @n::StringDelegatorObj.str_ivar1
+    assert_equal [:@str_ivar2, :@str_ivar3], @n::StringDelegatorObj.instance_variables
+
+    assert_equal [], String.instance_variables
+  end
+
   def test_methods_added_in_namespace_are_invisible_globally
     pend unless Namespace.enabled?
 
diff --git a/test/ruby/test_object_id.rb b/test/ruby/test_object_id.rb
index 44421ea256..9c0099517b 100644
--- a/test/ruby/test_object_id.rb
+++ b/test/ruby/test_object_id.rb
@@ -198,3 +198,49 @@ class TestObjectIdTooComplexGeneric < TestObjectId
     end
   end
 end
+
+class TestObjectIdRactor < Test::Unit::TestCase
+  def test_object_id_race_free
+    assert_separately([], "#{<<~"begin;"}\n#{<<~'end;'}")
+    begin;
+      Warning[:experimental] = false
+      class MyClass
+        attr_reader :a, :b, :c
+        def initialize
+          @a = @b = @c = nil
+        end
+      end
+      N = 10_000
+      objs = Ractor.make_shareable(N.times.map { MyClass.new })
+      results = 4.times.map{
+        Ractor.new(objs) { |objs|
+          vars = []
+          ids = []
+          objs.each do |obj|
+            vars << obj.a << obj.b << obj.c
+            ids << obj.object_id
+          end
+          [vars, ids]
+        }
+      }.map(&:value)
+      assert_equal 1, results.uniq.size
+    end;
+  end
+
+  def test_external_object_id_ractor_move
+    assert_separately([], "#{<<~"begin;"}\n#{<<~'end;'}")
+    begin;
+      Warning[:experimental] = false
+      class MyClass
+        attr_reader :a, :b, :c
+        def initialize
+          @a = @b = @c = nil
+        end
+      end
+      obj = Ractor.make_shareable(MyClass.new)
+      object_id = obj.object_id
+      obj = Ractor.new { Ractor.receive }.send(obj, move: true).value
+      assert_equal object_id, obj.object_id
+    end;
+  end
+end
diff --git a/test/ruby/test_ractor.rb b/test/ruby/test_ractor.rb
index b423993df1..3fc891da23 100644
--- a/test/ruby/test_ractor.rb
+++ b/test/ruby/test_ractor.rb
@@ -79,6 +79,26 @@ class TestRactor < Test::Unit::TestCase
     end;
   end
 
+  def test_class_instance_variables
+    assert_ractor(<<~'RUBY')
+      # Once we're in multi-ractor mode, the codepaths
+      # for class instance variables are a bit different.
+      Ractor.new {}.value
+
+      class TestClass
+        @a = 1
+        @b = 2
+        @c = 3
+        @d = 4
+      end
+
+      assert_equal 4, TestClass.remove_instance_variable(:@d)
+      assert_nil TestClass.instance_variable_get(:@d)
+      assert_equal 4, TestClass.instance_variable_set(:@d, 4)
+      assert_equal 4, TestClass.instance_variable_get(:@d)
+    RUBY
+  end
+
   def test_require_raises_and_no_ractor_belonging_issue
     assert_ractor(<<~'RUBY')
       require "tempfile"
@@ -98,6 +118,21 @@ class TestRactor < Test::Unit::TestCase
     RUBY
   end
 
+  def test_require_non_string
+    assert_ractor(<<~'RUBY')
+      require "tempfile"
+      require "pathname"
+      f = Tempfile.new(["file_to_require_from_ractor", ".rb"])
+      f.write("")
+      f.flush
+      result = Ractor.new(f.path) do |path|
+        require Pathname.new(path)
+        "success"
+      end.value
+      assert_equal "success", result
+    RUBY
+  end
+
   def assert_make_shareable(obj)
     refute Ractor.shareable?(obj), "object was already shareable"
     Ractor.make_shareable(obj)
diff --git a/test/ruby/test_rubyoptions.rb b/test/ruby/test_rubyoptions.rb
index 833b6a3b7d..54ad953ee9 100644
--- a/test/ruby/test_rubyoptions.rb
+++ b/test/ruby/test_rubyoptions.rb
@@ -787,6 +787,12 @@ class TestRubyOptions < Test::Unit::TestCase
     unless /mswin|mingw/ =~ RUBY_PLATFORM
       opts[:rlimit_core] = 0
     end
+    opts[:failed] = proc do |status, message = "", out = ""|
+      if (sig = status.termsig) && Signal.list["SEGV"] == sig
+        out = ""
+      end
+      Test::Unit::CoreAssertions::FailDesc[status, message]
+    end
     ExecOptions = opts.freeze
 
     # The regexp list that should match the entire stderr output.
@@ -836,8 +842,6 @@ class TestRubyOptions < Test::Unit::TestCase
   end
 
   def assert_segv(args, message=nil, list: SEGVTest::ExpectedStderrList, **opt, &block)
-    pend "macOS 15 is not working with this assertion" if macos?(15)
-
     # We want YJIT to be enabled in the subprocess if it's enabled for us
     # so that the Ruby description matches.
     env = Hash === args.first ? args.shift : {}
@@ -849,7 +853,11 @@ class TestRubyOptions < Test::Unit::TestCase
     args.unshift(env)
 
     test_stdin = ""
-    tests = [//, list] unless block
+    if !block
+      tests = [//, list, message]
+    elsif message
+      tests = [[], [], message]
+    end
 
     assert_in_out_err(args, test_stdin, *tests, encoding: "ASCII-8BIT",
                       **SEGVTest::ExecOptions, **opt, &block)
@@ -862,13 +870,12 @@ class TestRubyOptions < Test::Unit::TestCase
   def test_segv_loaded_features
     bug7402 = '[ruby-core:49573]'
 
-    status = assert_segv(['-e', "END {#{SEGVTest::KILL_SELF}}",
-                          '-e', 'class Bogus; def to_str; exit true; end; end',
-                          '-e', '$".clear',
-                          '-e', '$".unshift Bogus.new',
-                          '-e', '(p $"; abort) unless $".size == 1',
-                         ])
-    assert_not_predicate(status, :success?, "segv but success #{bug7402}")
+    assert_segv(['-e', "END {#{SEGVTest::KILL_SELF}}",
+                 '-e', 'class Bogus; def to_str; exit true; end; end',
+                 '-e', '$".clear',
+                 '-e', '$".unshift Bogus.new',
+                 '-e', '(p $"; abort) unless $".size == 1',
+                ], success: false)
   end
 
   def test_segv_setproctitle
@@ -881,8 +888,6 @@ class TestRubyOptions < Test::Unit::TestCase
   end
 
   def assert_crash_report(path, cmd = nil, &block)
-    pend "macOS 15 is not working with this assertion" if macos?(15)
-
     Dir.mktmpdir("ruby_crash_report") do |dir|
       list = SEGVTest::ExpectedStderrList
       if cmd
diff --git a/test/ruby/test_struct.rb b/test/ruby/test_struct.rb
index ecd8ed196c..db591c306e 100644
--- a/test/ruby/test_struct.rb
+++ b/test/ruby/test_struct.rb
@@ -550,6 +550,12 @@ module TestStruct
     CODE
   end
 
+  def test_frozen_subclass
+    test = Class.new(@Struct.new(:a)).freeze.new(a: 0)
+    assert_kind_of(@Struct, test)
+    assert_equal([:a], test.members)
+  end
+
   class TopStruct < Test::Unit::TestCase
     include TestStruct
 
diff --git a/test/ruby/test_variable.rb b/test/ruby/test_variable.rb
index 49fec2d40e..984045e05d 100644
--- a/test/ruby/test_variable.rb
+++ b/test/ruby/test_variable.rb
@@ -407,6 +407,20 @@ class TestVariable < Test::Unit::TestCase
     }
   end
 
+  def test_exivar_resize_with_compaction_stress
+    omit "compaction doesn't work well on s390x" if RUBY_PLATFORM =~ /s390x/ # https://github.com/ruby/ruby/pull/5077
+    objs = 10_000.times.map do
+      ExIvar.new
+    end
+    EnvUtil.under_gc_compact_stress do
+      10.times do
+        x = ExIvar.new
+        x.instance_variable_set(:@resize, 1)
+        x
+      end
+    end
+  end
+
   def test_local_variables_with_kwarg
     bug11674 = '[ruby-core:71437] [Bug #11674]'
     v = with_kwargs_11(v1:1,v2:2,v3:3,v4:4,v5:5,v6:6,v7:7,v8:8,v9:9,v10:10,v11:11)
diff --git a/test/ruby/test_vm_dump.rb b/test/ruby/test_vm_dump.rb
index 709fd5eadf..a3e7b69913 100644
--- a/test/ruby/test_vm_dump.rb
+++ b/test/ruby/test_vm_dump.rb
@@ -5,8 +5,6 @@ return unless /darwin/ =~ RUBY_PLATFORM
 
 class TestVMDump < Test::Unit::TestCase
   def assert_darwin_vm_dump_works(args, timeout=nil)
-    pend "macOS 15 is not working with this assertion" if macos?(15)
-
     assert_in_out_err(args, "", [], /^\[IMPORTANT\]/, timeout: timeout || 300)
   end
 
diff --git a/test/ruby/test_zjit.rb b/test/ruby/test_zjit.rb
index 47a9f6f7dc..2b171b02b1 100644
--- a/test/ruby/test_zjit.rb
+++ b/test/ruby/test_zjit.rb
@@ -31,6 +31,20 @@ class TestZJIT < Test::Unit::TestCase
     }
   end
 
+  def test_putstring
+    assert_compiles '""', %q{
+      def test = "#{""}"
+      test
+    }, insns: [:putstring]
+  end
+
+  def test_putchilldedstring
+    assert_compiles '""', %q{
+      def test = ""
+      test
+    }, insns: [:putchilledstring]
+  end
+
   def test_leave_param
     assert_compiles '5', %q{
       def test(n) = n
@@ -102,12 +116,39 @@ class TestZJIT < Test::Unit::TestCase
     }, call_threshold: 2
   end
 
+  def test_opt_plus_type_guard_exit_with_locals
+    assert_compiles '[6, 6.0]', %q{
+      def test(a)
+        local = 3
+        1 + a + local
+      end
+      test(1) # profile opt_plus
+      [test(2), test(2.0)]
+    }, call_threshold: 2
+  end
+
   def test_opt_plus_type_guard_nested_exit
-    omit 'rewind_caller_frames is not implemented yet'
-    assert_compiles '[3, 3.0]', %q{
+    assert_compiles '[4, 4.0]', %q{
       def side_exit(n) = 1 + n
       def jit_frame(n) = 1 + side_exit(n)
       def entry(n) = jit_frame(n)
+      entry(2) # profile send
+      [entry(2), entry(2.0)]
+    }, call_threshold: 2
+  end
+
+  def test_opt_plus_type_guard_nested_exit_with_locals
+    assert_compiles '[9, 9.0]', %q{
+      def side_exit(n)
+        local = 2
+        1 + n + local
+      end
+      def jit_frame(n)
+        local = 3
+        1 + side_exit(n) + local
+      end
+      def entry(n) = jit_frame(n)
+      entry(2) # profile send
       [entry(2), entry(2.0)]
     }, call_threshold: 2
   end
@@ -130,7 +171,6 @@ class TestZJIT < Test::Unit::TestCase
   end
 
   def test_opt_mult_overflow
-    omit 'side exits are not implemented yet'
     assert_compiles '[6, -6, 9671406556917033397649408, -9671406556917033397649408, 21267647932558653966460912964485513216]', %q{
       def test(a, b)
         a * b
@@ -255,6 +295,34 @@ class TestZJIT < Test::Unit::TestCase
     }, insns: [:opt_ge], call_threshold: 2
   end
 
+  def test_opt_hash_freeze
+    assert_compiles '{}', <<~RUBY, insns: [:opt_hash_freeze]
+      def test = {}.freeze
+      test
+    RUBY
+  end
+
+  def test_opt_ary_freeze
+    assert_compiles '[]', <<~RUBY, insns: [:opt_ary_freeze]
+      def test = [].freeze
+      test
+    RUBY
+  end
+
+  def test_opt_str_freeze
+    assert_compiles '""', <<~RUBY, insns: [:opt_str_freeze]
+      def test = "".freeze
+      test
+    RUBY
+  end
+
+  def test_opt_str_uminus
+    assert_compiles '""', <<~RUBY, insns: [:opt_str_uminus]
+      def test = -""
+      test
+    RUBY
+  end
+
   def test_new_array_empty
     assert_compiles '[]', %q{
       def test = []
@@ -610,6 +678,69 @@ class TestZJIT < Test::Unit::TestCase
     }
   end
 
+  def test_uncached_getconstant_path
+    assert_compiles RUBY_COPYRIGHT.dump, %q{
+      def test = RUBY_COPYRIGHT
+      test
+    }, call_threshold: 1, insns: [:opt_getconstant_path]
+  end
+
+  def test_getconstant_path_autoload
+    # A constant-referencing expression can run arbitrary code through Kernel#autoload.
+    Dir.mktmpdir('autoload') do |tmpdir|
+      autoload_path = File.join(tmpdir, 'test_getconstant_path_autoload.rb')
+      File.write(autoload_path, 'X = RUBY_COPYRIGHT')
+
+      assert_compiles RUBY_COPYRIGHT.dump, %Q{
+        Object.autoload(:X, #{File.realpath(autoload_path).inspect})
+        def test = X
+        test
+      }, call_threshold: 1, insns: [:opt_getconstant_path]
+    end
+  end
+
+  def test_send_backtrace
+    backtrace = [
+      "-e:2:in 'Object#jit_frame1'",
+      "-e:3:in 'Object#entry'",
+      "-e:5:in 'block in <main>'",
+      "-e:6:in '<main>'",
+    ]
+    assert_compiles backtrace.inspect, %q{
+      def jit_frame2 = caller     # 1
+      def jit_frame1 = jit_frame2 # 2
+      def entry = jit_frame1      # 3
+      entry # profile send        # 4
+      entry                       # 5
+    }, call_threshold: 2
+  end
+
+  def test_putspecialobject_vm_core_and_cbase
+    assert_compiles '10', %q{
+      def test
+        alias bar test
+        10
+      end
+
+      test
+      bar
+    }, insns: [:putspecialobject]
+  end
+
+  def test_putspecialobject_const_base
+    assert_compiles '1', %q{
+      Foo = 1
+
+      def test = Foo
+
+      # First call: populates the constant cache
+      test
+      # Second call: triggers ZJIT compilation with warm cache
+      # RubyVM::ZJIT.assert_compiles will panic if this fails to compile
+      test
+    }, call_threshold: 2
+  end
+
   # tool/ruby_vm/views/*.erb relies on the zjit instructions a) being contiguous and
   # b) being reliably ordered after all the other instructions.
   def test_instruction_order
@@ -631,11 +762,7 @@ class TestZJIT < Test::Unit::TestCase
     pipe_fd = 3
 
     script = <<~RUBY
-      _test_proc = -> {
-        RubyVM::ZJIT.assert_compiles
-        #{test_script}
-      }
-      ret_val = _test_proc.call
+      ret_val = (_test_proc = -> { RubyVM::ZJIT.assert_compiles; #{test_script.lstrip} }).call
       result = {
         ret_val:,
         #{ unless insns.empty?