diff --git a/tool/lib/test/unit/assertions.rb b/tool/lib/test/unit/assertions.rb
index 0c68a93b02..33f31fe203 100644
--- a/tool/lib/test/unit/assertions.rb
+++ b/tool/lib/test/unit/assertions.rb
@@ -216,35 +216,6 @@ module Test
         ret
       end
 
-      # :call-seq:
-      #   assert_throw( tag, failure_message = nil, &block )
-      #
-      #Fails unless the given block throws +tag+, returns the caught
-      #value otherwise.
-      #
-      #An optional failure message may be provided as the final argument.
-      #
-      #    tag = Object.new
-      #    assert_throw(tag, "#{tag} was not thrown!") do
-      #      throw tag
-      #    end
-      def assert_throw(tag, msg = nil)
-        ret = catch(tag) do
-          begin
-            yield(tag)
-          rescue UncaughtThrowError => e
-            thrown = e.tag
-          end
-          msg = message(msg) {
-            "Expected #{mu_pp(tag)} to have been thrown"\
-            "#{%Q[, not #{thrown}] if thrown}"
-          }
-          assert(false, msg)
-        end
-        assert(true)
-        ret
-      end
-
       # :call-seq:
       #   assert_equal( expected, actual, failure_message = nil )
       #
@@ -551,14 +522,6 @@ EOT
         assert !status.signaled?, FailDesc[status, message, out]
       end
 
-      def assert_ruby_status(args, test_stdin="", message=nil, **opt)
-        out, _, status = EnvUtil.invoke_ruby(args, test_stdin, true, :merge_to_stdout, **opt)
-        desc = FailDesc[status, message, out]
-        assert(!status.signaled?, desc)
-        message ||= "ruby exit status is not success:"
-        assert(status.success?, desc)
-      end
-
       def assert_warning(pat, msg = nil)
         result = nil
         stderr = EnvUtil.with_default_internal(pat.encoding) {
diff --git a/tool/lib/test/unit/core_assertions.rb b/tool/lib/test/unit/core_assertions.rb
index 5533c54634..b637748e5e 100644
--- a/tool/lib/test/unit/core_assertions.rb
+++ b/tool/lib/test/unit/core_assertions.rb
@@ -114,6 +114,14 @@ module Test
         end
       end
 
+      def assert_ruby_status(args, test_stdin="", message=nil, **opt)
+        out, _, status = EnvUtil.invoke_ruby(args, test_stdin, true, :merge_to_stdout, **opt)
+        desc = FailDesc[status, message, out]
+        assert(!status.signaled?, desc)
+        message ||= "ruby exit status is not success:"
+        assert(status.success?, desc)
+      end
+
       ABORT_SIGNALS = Signal.list.values_at(*%w"ILL ABRT BUS SEGV TERM")
 
       def assert_separately(args, file = nil, line = nil, src, ignore_stderr: nil, **opt)
@@ -165,6 +173,35 @@ eom
         raise marshal_error if marshal_error
       end
 
+      # :call-seq:
+      #   assert_throw( tag, failure_message = nil, &block )
+      #
+      #Fails unless the given block throws +tag+, returns the caught
+      #value otherwise.
+      #
+      #An optional failure message may be provided as the final argument.
+      #
+      #    tag = Object.new
+      #    assert_throw(tag, "#{tag} was not thrown!") do
+      #      throw tag
+      #    end
+      def assert_throw(tag, msg = nil)
+        ret = catch(tag) do
+          begin
+            yield(tag)
+          rescue UncaughtThrowError => e
+            thrown = e.tag
+          end
+          msg = message(msg) {
+            "Expected #{mu_pp(tag)} to have been thrown"\
+            "#{%Q[, not #{thrown}] if thrown}"
+          }
+          assert(false, msg)
+        end
+        assert(true)
+        ret
+      end
+
       class << (AssertFile = Struct.new(:failure_message).new)
         include CoreAssertions
         def assert_file_predicate(predicate, *args)