Introduce `Psych.unsafe_load`

In future versions of Psych, the `load` method will be mostly the same
as the `safe_load` method.  In other words, the `load` method won't
allow arbitrary object deserialization (which can be used to escalate to
an RCE).  People that need to load *trusted* documents can use the
`unsafe_load` method.

This commit introduces the `unsafe_load` method so that people can
incrementally upgrade.  For example, if they try to upgrade to 4.0.0 and
something breaks, they can downgrade, audit callsites, change to
`safe_load` or `unsafe_load` as required, and then upgrade to 4.0.0
smoothly.

1 files changed, 2 insertions, 2 deletions

diff --git a/test/psych/visitors/test_to_ruby.rb b/test/psych/visitors/test_to_ruby.rb
index e1a0056..3d4608b 100644
--- a/test/psych/visitors/test_to_ruby.rb
+++ b/test/psych/visitors/test_to_ruby.rb
@@ -20,13 +20,13 @@ module Psych
       end
 
       def test_tz_00_00_loads_without_error
-        assert Psych.load('1900-01-01T00:00:00+00:00')
+        assert Psych.unsafe_load('1900-01-01T00:00:00+00:00')
       end
 
       def test_legacy_struct
         Struct.send(:remove_const, :AWESOME) if Struct.const_defined?(:AWESOME)
         foo = Struct.new('AWESOME', :bar)
-        assert_equal foo.new('baz'), Psych.load(<<-eoyml)
+        assert_equal foo.new('baz'), Psych.unsafe_load(<<-eoyml)
 !ruby/struct:AWESOME
   bar: baz
         eoyml