test/rake: fix tests under test-all

* test/rake/test_rake_application.rb (test_display_exception_details):
  `RbConfig::CONFIG["prefix"]` can be the root directory, under
  test-all.

* test/rake/test_rake_test_task.rb (test_run_code_rake_default_gem):
  `-I` may be inserted, under test-all.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@46890 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

test/rake/test_rake_application.rb

@@ -17,8 +17,10 @@ class TestRakeApplication < Rake::TestCase
   end
 
   def test_display_exception_details
+    obj = Object.new
+    obj.instance_eval("def #{__method__}; raise 'test'; end", "ruby")
     begin
-      raise 'test'
+      obj.__send__(__method__)
     rescue => ex
     end
 

test/rake/test_rake_test_task.rb

@@ -105,7 +105,7 @@ class TestRakeTestTask < Rake::TestCase
       t.loader = :rake
     end
 
-    assert_match(/\A ".*?"\Z/, test_task.run_code)
+    assert_match(/\A(-I".*?" *)* ".*?"\Z/, test_task.run_code)
   ensure
     Gem.loaded_specs['rake'] = rake
   end