Bug #967
closedResults of const_missing are being cached incorrectly
Description
=begin
Ruby 1.9 sped up constant lookup by adding an inline cache, cleared by a global serial number incremented when any constant is set. This works well for normal constants, but unfortunately 1.9 is also caching the result of const_missing. For example, the following output:
◆ ruby1.9 -e "def Object.const_missing(sym); Time.now; end; 5.times { p XXX; sleep 1 }"
2009-01-01 23:59:33 -0600
2009-01-01 23:59:33 -0600
2009-01-01 23:59:33 -0600
2009-01-01 23:59:33 -0600
2009-01-01 23:59:33 -0600
The result of const_missing is being cached at the lookup site for XXX. Here's what the output should look like, with incrementing seconds:
◆ ruby -e "def Object.const_missing(sym); Time.now; end; 5.times { p XXX; sleep 1 }"
Fri Jan 02 00:02:09 -0600 2009
Fri Jan 02 00:02:10 -0600 2009
Fri Jan 02 00:02:11 -0600 2009
Fri Jan 02 00:02:12 -0600 2009
Fri Jan 02 00:02:13 -0600 2009
Note that this also affects colon2 and colon3 constant lookup:
◆ ruby1.9 -e "def Object.const_missing(sym); cls = Class.new; cls.class_eval 'Foo = Time.now'; cls; end; 5.times { p XXX::Foo; sleep 1 }"
2009-01-02 00:02:44 -0600
2009-01-02 00:02:44 -0600
2009-01-02 00:02:44 -0600
2009-01-02 00:02:44 -0600
2009-01-02 00:02:44 -0600
◆ ruby1.9 -e "def Object.const_missing(sym); Time.now; end; 5.times { p ::XXX; sleep 1 }"
2009-01-02 00:03:06 -0600
2009-01-02 00:03:06 -0600
2009-01-02 00:03:06 -0600
2009-01-02 00:03:06 -0600
2009-01-02 00:03:06 -0600
The result of const_missing should never be cached, since doing so would break code that expects const_missing to keep firing (some DSLs for example).
This was run against the just-released Ruby 1.9 RC.
=end
Updated by ko1 (Koichi Sasada) almost 16 years ago
- Status changed from Open to Closed
- % Done changed from 0 to 100
=begin
Applied in changeset r21536.
=end