I suspect this is a load order problem. After the release of 0.9.6
, Mocha no longer loads Test::Unit itself. Instead Mocha now needs
you to load Test::Unit *before* you load Mocha. Exactly how you solve
this depends on how you are currently loading Test::Unit and Mocha,
but usually it may simply be a matter of moving a require 'mocha'
statement below a require 'test/unit' statement.
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