2 files changed, 37 insertions, 0 deletions
diff --git a/test/mmtk/helper.rb b/test/mmtk/helper.rb
new file mode 100644
index 0000000000..e4cff30389
--- /dev/null
+++ b/test/mmtk/helper.rb
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+require "test/unit"
+require "core_assertions"
+
+module MMTk
+  class TestCase < ::Test::Unit::TestCase
+    include Test::Unit::CoreAssertions
+
+    def setup
+      omit "Not running on MMTk" unless using_mmtk?
+      super
+    end
+
+    private
+
+    def using_mmtk?
+      GC.config[:implementation] == "mmtk"
+    end
+  end
+end
diff --git a/test/mmtk/test_configuration.rb b/test/mmtk/test_configuration.rb
new file mode 100644
index 0000000000..1191a27e6d
--- /dev/null
+++ b/test/mmtk/test_configuration.rb
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+require_relative "helper"
+module MMTk
+  class TestConfiguration < TestCase
+    def test_invalid_MMTK_THREADS
+      exit_code = assert_in_out_err(
+        [{ "MMTK_THREADS" => "foobar" }, "--"],
+        "",
+        [],
+        ["[FATAL] Invalid MMTK_THREADS foobar"]
+      )
+
+      assert_equal(1, exit_code.exitstatus)
+    end
+  end
+end