Add spec to class name definition in newgem spec

bundler/spec/commands/newgem_spec.rb

@@ -30,6 +30,8 @@ def bundle_exec_standardrb
 
   let(:minitest_test_file_path) { "test/test_mygem.rb" }
 
+  let(:minitest_test_class_name) { "class TestMygem < Minitest::Test" }
+
   before do
     sys_exec("git config --global user.name 'Bundler User'")
     sys_exec("git config --global user.email user@example.com")
@@ -736,6 +738,10 @@ def create_temporary_dir(dir)
         expect(bundled_app("#{gem_name}/#{minitest_test_file_path}").read).to include(%(require "test_helper"))
       end
 
+      it "defines valid test class name" do
+        expect(bundled_app("#{gem_name}/#{minitest_test_file_path}").read).to include(minitest_test_class_name)
+      end
+
       it "creates a default test which fails" do
         expect(bundled_app("#{gem_name}/#{minitest_test_file_path}").read).to include("assert false")
       end
@@ -1304,6 +1310,8 @@ def create_temporary_dir(dir)
 
     let(:minitest_test_file_path) { "test/test_test_gem.rb" }
 
+    let(:minitest_test_class_name) { "class TestTestGem < Minitest::Test" }
+
     let(:flags) { nil }
 
     it "does not nest constants" do
@@ -1361,6 +1369,8 @@ def create_temporary_dir(dir)
 
     let(:minitest_test_file_path) { "test/test/test_gem.rb" }
 
+    let(:minitest_test_class_name) { "class TestTestGem < Minitest::Test" }
+
     it "nests constants so they work" do
       bundle "gem #{gem_name}"
       expect(bundled_app("#{gem_name}/lib/#{require_path}/version.rb").read).to match(/module Test\n  module Gem/)