Are there plans to bring back metrictest?

[mfridman]

There used to be a metrictest package that made it possible to test metrics collection in testing code.

I see it has been removed, but are there plans to bring it back?

If not, is there a recommendation on testing a metric.MeterProvider. Is there something in the Go otel package that could satisfy that interface?

[dmathieu]

There are assertions available in the metricdatatest package.

The idea is to use this with a manual reader in your tests:

rdr := sdkmetric.NewManualReader()
mp := sdkmetric.NewMeterProvider(sdkmetric.WithReader(rdr))

Pass the meter provider so it's used within your tested code.
And when you want to retrieve metrics data (to use the provided assertions, or write your own), you can use the reader's Collect method.

var data metricdata.ResourceMetrics
err := rdr.Collect(context.Background(), &data)

// Check for no error, and that the provided data is as expected.