1 files changed, 58 insertions, 0 deletions
diff --git a/test/rubygems/test_project_sanity.rb b/test/rubygems/test_project_sanity.rb
new file mode 100644
index 0000000000..72f5e3b36e
--- /dev/null
+++ b/test/rubygems/test_project_sanity.rb
@@ -0,0 +1,58 @@
+# frozen_string_literal: true
+
+require "rubygems/test_case"
+require "open3"
+
+class TestProjectSanity < Minitest::Test
+
+  def test_rake_package_builds_ok
+    skip unless File.exist?(File.expand_path("../../../Rakefile", __FILE__))
+
+    with_empty_pkg_folder do
+      output, status = Open3.capture2e("rake package")
+
+      assert_equal true, status.success?, <<~MSG.chomp
+        Expected `rake package` to work, but got errors:
+
+        ```
+        #{output}
+        ```
+
+        If you have added or removed files, make sure you run `rake update_manifest` to update the `Manifest.txt` accordingly
+      MSG
+    end
+  end
+
+  def test_manifest_is_up_to_date
+    skip unless File.exist?(File.expand_path("../../../Rakefile", __FILE__))
+
+    _, status = Open3.capture2e("rake check_manifest")
+
+    assert status.success?, "Expected Manifest.txt to be up to date, but it's not. Run `rake update_manifest` to sync it."
+  end
+
+  private
+
+  def with_empty_pkg_folder
+    if File.exist?("pkg")
+      FileUtils.cp_r("pkg", "tmp")
+
+      begin
+        FileUtils.rm_rf("pkg")
+        yield
+      ensure
+        FileUtils.rm_rf("pkg")
+        FileUtils.cp_r("tmp/pkg", ".")
+      end
+    else
+      Dir.mkdir("pkg")
+
+      begin
+        yield
+      ensure
+        FileUtils.rm_rf("pkg")
+      end
+    end
+  end
+
+end