IssueTracker

We want to expose, through a listener, the metric measurements for each iteration and test. This would allow users to build some mechanism to store previous benchmark results (one or more) that could be used for regression and trend analysis over time.

An example of the callback would look like:

@get:Rule
val benchmarkRule = MacrobenchmarkRule(
    onBenchmarkResult = { benchmarkResults ->
        // Record them as instrumentation results or other post processing
    }
)

@Test
fun myBenchmark() {
    benchmarkRule.measureRepeated(
        packageName = PACKAGE_NAME,
        metrics = listOf(FrameTimingMetric()),
        iterations = 10,
        setupBlock = { startActivityAndWait(Intent(ACTION)) }
    ) {
        // Some action to benchmark.
    }
}

Note that iteration results are already reported as instrumentation: https://developer.android.com/topic/performance/benchmarking/benchmarking-in-ci#benchmark-data-example

It's a pretty manual process at the moment but raw data allows other analysis also off-device