[ruby/psych] 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.

https://github.com/ruby/psych/commit/cb50aa8d3f

1 files changed, 7 insertions, 7 deletions

diff --git a/test/psych/test_string.rb b/test/psych/test_string.rb
index 973f38b9c2..20ab79c05a 100644
--- a/test/psych/test_string.rb
+++ b/test/psych/test_string.rb
@@ -104,7 +104,7 @@ module Psych
     end
 
     def test_string_subclass_with_anchor
-      y = Psych.load <<-eoyml
+      y = Psych.unsafe_load <<-eoyml
 ---
 body:
   string: &70121654388580 !ruby/string
@@ -116,7 +116,7 @@ body:
     end
 
     def test_self_referential_string
-      y = Psych.load <<-eoyml
+      y = Psych.unsafe_load <<-eoyml
 ---
 string: &70121654388580 !ruby/string
   str: ! 'foo'
@@ -129,32 +129,32 @@ string: &70121654388580 !ruby/string
     end
 
     def test_another_subclass_with_attributes
-      y = Psych.load Psych.dump Y.new("foo").tap {|o| o.val = 1}
+      y = Psych.unsafe_load Psych.dump Y.new("foo").tap {|o| o.val = 1}
       assert_equal "foo", y
       assert_equal Y, y.class
       assert_equal 1, y.val
     end
 
     def test_backwards_with_syck
-      x = Psych.load "--- !str:#{X.name} foo\n\n"
+      x = Psych.unsafe_load "--- !str:#{X.name} foo\n\n"
       assert_equal X, x.class
       assert_equal 'foo', x
     end
 
     def test_empty_subclass
       assert_match "!ruby/string:#{X}", Psych.dump(X.new)
-      x = Psych.load Psych.dump X.new
+      x = Psych.unsafe_load Psych.dump X.new
       assert_equal X, x.class
     end
 
     def test_empty_character_subclass
       assert_match "!ruby/string:#{Z}", Psych.dump(Z.new)
-      x = Psych.load Psych.dump Z.new
+      x = Psych.unsafe_load Psych.dump Z.new
       assert_equal Z, x.class
     end
 
     def test_subclass_with_attributes
-      y = Psych.load Psych.dump Y.new.tap {|o| o.val = 1}
+      y = Psych.unsafe_load Psych.dump Y.new.tap {|o| o.val = 1}
       assert_equal Y, y.class
       assert_equal 1, y.val
     end