Use CaptureBackend in Test environment

[nTraum]

Hi statsd-instrument team,

I want to provide convenient RSpec matchers for this gem (similar to your minitest assertions) and was wondering why the CaptureBackend is not used by default in test environments (but the NullBackend instead).

In my opinion this would simplify the implementation a lot, instead of mocking & replacing the NullBackend with a CaptureBackend in a block (as done currently), you'd just need to configure the Backend once (either in a spec_helper explicitly or via ENVs implicitly).

What do you think?

[wvanbergen]

Two reasons:

• First of all, we want to make sure the StatsD packet is actually generated inside the code block of the assert call, not before or after. So we should only capture inside the block.
• Second: our test suite is big, and we generate lots of StatsD calls. This would require a lot of memory during the test run as we accumulate thousands of metrics.

In RSpec, I'd expect something like expect { ... }.to generate_statsd_call(...). You can easily do the same trick with the block here.

[nTraum]

Valid points, thanks for the quick response!