rails/rails — pull request #8298 by Empact (2012-11-23 07:49:16+00:00)
Title: In ActiveRecord::Inheritance.compute_type, only swallow the NameErrors arising directly from the failed lookup attempts.

This fix prevents us from improperly swallowing errors, e.g when the module being looked up includes an bad reference in its definition.

NameError#missing_name? seems to be the proper way these lookup errors are filtered out elsewhere.