How to reset constants in tests?

[Ben Johnson]

I am writing tests for configuration options that make class level
changes. Because they are class level, the changes get carried over to
the next test. What would be the best way to accomplish "transactions"
for ruby constants. Basically a way to rollback any class level changes
that were made during the test.

Thanks!

 

[David A. Black]

Hi --

I am writing tests for configuration options that make class level
changes. Because they are class level, the changes get carried over to
the next test. What would be the best way to accomplish "transactions"
for ruby constants. Basically a way to rollback any class level changes
that were made during the test.

The first thing that comes to mind is something like this (untested,
and you'd have to adapt it a lot anyway):

def change_option(const_name, value, klass)
old_value = klass.const_get(const_name)
klass.const_set(const_name, value)
yield
klass.const_set(const_name, old_value)
end

def test_something
change_option("OPTION", value, klass) do
...
end
end


David

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