Remove several metrics test helpers (#2105)

* Remove several metrics test helpers

* Lint

* Changelog

* Lint

CHANGELOG.md

@@ -23,6 +23,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 
 - Removed the deprecated package `go.opentelemetry.io/otel/exporters/trace/jaeger`. (#2020)
 - Removed the deprecated package `go.opentelemetry.io/otel/exporters/trace/zipkin`. (#2020)
+- Removed metrics test package `go.opentelemetry.io/otel/sdk/export/metric/metrictest`. (#2105)
 
 ### Fixed
 

exporters/otlp/otlpmetric/exporter_test.go

@@ -22,7 +22,6 @@ import (
 
 	"go.opentelemetry.io/otel/exporters/otlp/otlpmetric"
 	"go.opentelemetry.io/otel/sdk/export/metric/aggregation"
-	"go.opentelemetry.io/otel/sdk/export/metric/metrictest"
 	"go.opentelemetry.io/otel/sdk/metric/aggregator/histogram"
 	"go.opentelemetry.io/otel/sdk/metric/aggregator/sum"
 
@@ -764,9 +763,11 @@ func runMetricExportTests(t *testing.T, opts []otlpmetric.Option, rs []record, e
 
 		var agg, ckpt metricsdk.Aggregator
 		if r.iKind.Adding() {
-			agg, ckpt = metrictest.Unslice2(sum.New(2))
+			sums := sum.New(2)
+			agg, ckpt = &sums[0], &sums[1]
 		} else {
-			agg, ckpt = metrictest.Unslice2(histogram.New(2, &desc, histogram.WithExplicitBoundaries(testHistogramBoundaries)))
+			histos := histogram.New(2, &desc, histogram.WithExplicitBoundaries(testHistogramBoundaries))
+			agg, ckpt = &histos[0], &histos[1]
 		}
 
 		ctx := context.Background()

exporters/otlp/otlpmetric/internal/metrictransform/metric_test.go

@@ -29,7 +29,6 @@ import (
 	"go.opentelemetry.io/otel/metric/number"
 	export "go.opentelemetry.io/otel/sdk/export/metric"
 	"go.opentelemetry.io/otel/sdk/export/metric/aggregation"
-	"go.opentelemetry.io/otel/sdk/export/metric/metrictest"
 	arrAgg "go.opentelemetry.io/otel/sdk/metric/aggregator/exact"
 	"go.opentelemetry.io/otel/sdk/metric/aggregator/lastvalue"
 	lvAgg "go.opentelemetry.io/otel/sdk/metric/aggregator/lastvalue"
@@ -101,18 +100,19 @@ func TestStringKeyValues(t *testing.T) {
 }
 
 func TestMinMaxSumCountValue(t *testing.T) {
-	mmsc, ckpt := metrictest.Unslice2(minmaxsumcount.New(2, &metric.Descriptor{}))
+	mmscs := minmaxsumcount.New(2, &metric.Descriptor{})
+	mmsc, ckpt := &mmscs[0], &mmscs[1]
 
 	assert.NoError(t, mmsc.Update(context.Background(), 1, &metric.Descriptor{}))
 	assert.NoError(t, mmsc.Update(context.Background(), 10, &metric.Descriptor{}))
 
 	// Prior to checkpointing ErrNoData should be returned.
-	_, _, _, _, err := minMaxSumCountValues(ckpt.(aggregation.MinMaxSumCount))
+	_, _, _, _, err := minMaxSumCountValues(ckpt)
 	assert.EqualError(t, err, aggregation.ErrNoData.Error())
 
 	// Checkpoint to set non-zero values
 	require.NoError(t, mmsc.SynchronizedMove(ckpt, &metric.Descriptor{}))
-	min, max, sum, count, err := minMaxSumCountValues(ckpt.(aggregation.MinMaxSumCount))
+	min, max, sum, count, err := minMaxSumCountValues(ckpt)
 	if assert.NoError(t, err) {
 		assert.Equal(t, min, number.NewInt64Number(1))
 		assert.Equal(t, max, number.NewInt64Number(10))
@@ -124,7 +124,8 @@ func TestMinMaxSumCountValue(t *testing.T) {
 func TestMinMaxSumCountDatapoints(t *testing.T) {
 	desc := metric.NewDescriptor("", metric.ValueRecorderInstrumentKind, number.Int64Kind)
 	labels := attribute.NewSet(attribute.String("one", "1"))
-	mmsc, ckpt := metrictest.Unslice2(minmaxsumcount.New(2, &desc))
+	mmscs := minmaxsumcount.New(2, &metric.Descriptor{})
+	mmsc, ckpt := &mmscs[0], &mmscs[1]
 
 	assert.NoError(t, mmsc.Update(context.Background(), 1, &desc))
 	assert.NoError(t, mmsc.Update(context.Background(), 10, &desc))
@@ -154,7 +155,7 @@ func TestMinMaxSumCountDatapoints(t *testing.T) {
 		},
 	}
 	record := export.NewRecord(&desc, &labels, nil, ckpt.Aggregation(), intervalStart, intervalEnd)
-	m, err := minMaxSumCount(record, ckpt.(aggregation.MinMaxSumCount))
+	m, err := minMaxSumCount(record, ckpt)
 	if assert.NoError(t, err) {
 		assert.Nil(t, m.GetGauge())
 		assert.Nil(t, m.GetSum())
@@ -179,13 +180,14 @@ func TestMinMaxSumCountPropagatesErrors(t *testing.T) {
 func TestSumIntDataPoints(t *testing.T) {
 	desc := metric.NewDescriptor("", metric.ValueRecorderInstrumentKind, number.Int64Kind)
 	labels := attribute.NewSet(attribute.String("one", "1"))
-	s, ckpt := metrictest.Unslice2(sumAgg.New(2))
+	sums := sumAgg.New(2)
+	s, ckpt := &sums[0], &sums[1]
+
 	assert.NoError(t, s.Update(context.Background(), number.Number(1), &desc))
 	require.NoError(t, s.SynchronizedMove(ckpt, &desc))
 	record := export.NewRecord(&desc, &labels, nil, ckpt.Aggregation(), intervalStart, intervalEnd)
-	sum, ok := ckpt.(aggregation.Sum)
-	require.True(t, ok, "ckpt is not an aggregation.Sum: %T", ckpt)
-	value, err := sum.Sum()
+
+	value, err := ckpt.Sum()
 	require.NoError(t, err)
 
 	if m, err := sumPoint(record, value, record.StartTime(), record.EndTime(), export.CumulativeExportKind, true); assert.NoError(t, err) {
@@ -218,13 +220,13 @@ func TestSumIntDataPoints(t *testing.T) {
 func TestSumFloatDataPoints(t *testing.T) {
 	desc := metric.NewDescriptor("", metric.ValueRecorderInstrumentKind, number.Float64Kind)
 	labels := attribute.NewSet(attribute.String("one", "1"))
-	s, ckpt := metrictest.Unslice2(sumAgg.New(2))
+	sums := sumAgg.New(2)
+	s, ckpt := &sums[0], &sums[1]
+
 	assert.NoError(t, s.Update(context.Background(), number.NewFloat64Number(1), &desc))
 	require.NoError(t, s.SynchronizedMove(ckpt, &desc))
 	record := export.NewRecord(&desc, &labels, nil, ckpt.Aggregation(), intervalStart, intervalEnd)
-	sum, ok := ckpt.(aggregation.Sum)
-	require.True(t, ok, "ckpt is not an aggregation.Sum: %T", ckpt)
-	value, err := sum.Sum()
+	value, err := ckpt.Sum()
 	require.NoError(t, err)
 
 	if m, err := sumPoint(record, value, record.StartTime(), record.EndTime(), export.DeltaExportKind, false); assert.NoError(t, err) {
@@ -256,13 +258,13 @@ func TestSumFloatDataPoints(t *testing.T) {
 func TestLastValueIntDataPoints(t *testing.T) {
 	desc := metric.NewDescriptor("", metric.ValueRecorderInstrumentKind, number.Int64Kind)
 	labels := attribute.NewSet(attribute.String("one", "1"))
-	s, ckpt := metrictest.Unslice2(lvAgg.New(2))
-	assert.NoError(t, s.Update(context.Background(), number.Number(100), &desc))
-	require.NoError(t, s.SynchronizedMove(ckpt, &desc))
+	lvs := lvAgg.New(2)
+	lv, ckpt := &lvs[0], &lvs[1]
+
+	assert.NoError(t, lv.Update(context.Background(), number.Number(100), &desc))
+	require.NoError(t, lv.SynchronizedMove(ckpt, &desc))
 	record := export.NewRecord(&desc, &labels, nil, ckpt.Aggregation(), intervalStart, intervalEnd)
-	sum, ok := ckpt.(aggregation.LastValue)
-	require.True(t, ok, "ckpt is not an aggregation.LastValue: %T", ckpt)
-	value, timestamp, err := sum.LastValue()
+	value, timestamp, err := ckpt.LastValue()
 	require.NoError(t, err)
 
 	if m, err := gaugePoint(record, value, time.Time{}, timestamp); assert.NoError(t, err) {
@@ -291,13 +293,13 @@ func TestLastValueIntDataPoints(t *testing.T) {
 func TestExactIntDataPoints(t *testing.T) {
 	desc := metric.NewDescriptor("", metric.ValueRecorderInstrumentKind, number.Int64Kind)
 	labels := attribute.NewSet(attribute.String("one", "1"))
-	e, ckpt := metrictest.Unslice2(arrAgg.New(2))
+	arrs := arrAgg.New(2)
+	e, ckpt := &arrs[0], &arrs[1]
+
 	assert.NoError(t, e.Update(context.Background(), number.Number(100), &desc))
 	require.NoError(t, e.SynchronizedMove(ckpt, &desc))
 	record := export.NewRecord(&desc, &labels, nil, ckpt.Aggregation(), intervalStart, intervalEnd)
-	p, ok := ckpt.(aggregation.Points)
-	require.True(t, ok, "ckpt is not an aggregation.Points: %T", ckpt)
-	pts, err := p.Points()
+	pts, err := ckpt.Points()
 	require.NoError(t, err)
 
 	if m, err := gaugeArray(record, pts); assert.NoError(t, err) {
@@ -326,13 +328,12 @@ func TestExactIntDataPoints(t *testing.T) {
 func TestExactFloatDataPoints(t *testing.T) {
 	desc := metric.NewDescriptor("", metric.ValueRecorderInstrumentKind, number.Float64Kind)
 	labels := attribute.NewSet(attribute.String("one", "1"))
-	e, ckpt := metrictest.Unslice2(arrAgg.New(2))
+	arrs := arrAgg.New(2)
+	e, ckpt := &arrs[0], &arrs[1]
 	assert.NoError(t, e.Update(context.Background(), number.NewFloat64Number(100), &desc))
 	require.NoError(t, e.SynchronizedMove(ckpt, &desc))
 	record := export.NewRecord(&desc, &labels, nil, ckpt.Aggregation(), intervalStart, intervalEnd)
-	p, ok := ckpt.(aggregation.Points)
-	require.True(t, ok, "ckpt is not an aggregation.Points: %T", ckpt)
-	pts, err := p.Points()
+	pts, err := ckpt.Points()
 	require.NoError(t, err)
 
 	if m, err := gaugeArray(record, pts); assert.NoError(t, err) {

exporters/stdout/stdoutmetric/metric_test.go

@@ -30,19 +30,18 @@ import (
 
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/metric"
-	"go.opentelemetry.io/otel/metric/number"
 	export "go.opentelemetry.io/otel/sdk/export/metric"
-	"go.opentelemetry.io/otel/sdk/export/metric/metrictest"
-	"go.opentelemetry.io/otel/sdk/metric/aggregator/aggregatortest"
-	"go.opentelemetry.io/otel/sdk/metric/aggregator/lastvalue"
-	"go.opentelemetry.io/otel/sdk/metric/aggregator/minmaxsumcount"
-	"go.opentelemetry.io/otel/sdk/metric/aggregator/sum"
+	controller "go.opentelemetry.io/otel/sdk/metric/controller/basic"
+	processor "go.opentelemetry.io/otel/sdk/metric/processor/basic"
+	"go.opentelemetry.io/otel/sdk/metric/processor/processortest"
 	"go.opentelemetry.io/otel/sdk/resource"
 )
 
 type testFixture struct {
 	t        *testing.T
 	ctx      context.Context
+	cont     *controller.Controller
+	meter    metric.Meter
 	exporter *stdoutmetric.Exporter
 	output   *bytes.Buffer
 }
@@ -50,6 +49,10 @@ type testFixture struct {
 var testResource = resource.NewSchemaless(attribute.String("R", "V"))
 
 func newFixture(t *testing.T, opts ...stdoutmetric.Option) testFixture {
+	return newFixtureWithResource(t, testResource, opts...)
+}
+
+func newFixtureWithResource(t *testing.T, res *resource.Resource, opts ...stdoutmetric.Option) testFixture {
 	buf := &bytes.Buffer{}
 	opts = append(opts, stdoutmetric.WithWriter(buf))
 	opts = append(opts, stdoutmetric.WithoutTimestamps())
@@ -57,10 +60,22 @@ func newFixture(t *testing.T, opts ...stdoutmetric.Option) testFixture {
 	if err != nil {
 		t.Fatal("Error building fixture: ", err)
 	}
+	aggSel := processortest.AggregatorSelector()
+	proc := processor.New(aggSel, export.StatelessExportKindSelector())
+	cont := controller.New(proc,
+		controller.WithExporter(exp),
+		controller.WithResource(res),
+	)
+	ctx := context.Background()
+	require.NoError(t, cont.Start(ctx))
+	meter := cont.MeterProvider().Meter("test")
+
 	return testFixture{
 		t:        t,
-		ctx:      context.Background(),
+		ctx:      ctx,
 		exporter: exp,
+		cont:     cont,
+		meter:    meter,
 		output:   buf,
 	}
 }
@@ -69,41 +84,33 @@ func (fix testFixture) Output() string {
 	return strings.TrimSpace(fix.output.String())
 }
 
-func (fix testFixture) Export(checkpointSet export.CheckpointSet) {
-	err := fix.exporter.Export(fix.ctx, checkpointSet)
-	if err != nil {
-		fix.t.Error("export failed: ", err)
-	}
-}
-
 func TestStdoutTimestamp(t *testing.T) {
 	var buf bytes.Buffer
+	aggSel := processortest.AggregatorSelector()
+	proc := processor.New(aggSel, export.CumulativeExportKindSelector())
 	exporter, err := stdoutmetric.New(
 		stdoutmetric.WithWriter(&buf),
 	)
 	if err != nil {
 		t.Fatal("Invalid config: ", err)
 	}
+	cont := controller.New(proc,
+		controller.WithExporter(exporter),
+		controller.WithResource(testResource),
+	)
+	ctx := context.Background()
+
+	require.NoError(t, cont.Start(ctx))
+	meter := cont.MeterProvider().Meter("test")
+	counter := metric.Must(meter).NewInt64Counter("name.lastvalue")
 
 	before := time.Now()
 	// Ensure the timestamp is after before.
 	time.Sleep(time.Nanosecond)
 
-	checkpointSet := metrictest.NewCheckpointSet(testResource)
+	counter.Add(ctx, 1)
 
-	ctx := context.Background()
-	desc := metric.NewDescriptor("test.name", metric.ValueObserverInstrumentKind, number.Int64Kind)
-
-	lvagg, ckpt := metrictest.Unslice2(lastvalue.New(2))
-
-	aggregatortest.CheckedUpdate(t, lvagg, number.NewInt64Number(321), &desc)
-	require.NoError(t, lvagg.SynchronizedMove(ckpt, &desc))
-
-	checkpointSet.Add(&desc, ckpt)
-
-	if err := exporter.Export(ctx, checkpointSet); err != nil {
-		t.Fatal("Unexpected export error: ", err)
-	}
+	require.NoError(t, cont.Stop(ctx))
 
 	// Ensure the timestamp is before after.
 	time.Sleep(time.Nanosecond)
@@ -131,129 +138,71 @@ func TestStdoutTimestamp(t *testing.T) {
 func TestStdoutCounterFormat(t *testing.T) {
 	fix := newFixture(t)
 
-	checkpointSet := metrictest.NewCheckpointSet(testResource)
+	counter := metric.Must(fix.meter).NewInt64Counter("name.sum")
+	counter.Add(fix.ctx, 123, attribute.String("A", "B"), attribute.String("C", "D"))
 
-	desc := metric.NewDescriptor("test.name", metric.CounterInstrumentKind, number.Int64Kind)
+	require.NoError(t, fix.cont.Stop(fix.ctx))
 
-	cagg, ckpt := metrictest.Unslice2(sum.New(2))
-
-	aggregatortest.CheckedUpdate(fix.t, cagg, number.NewInt64Number(123), &desc)
-	require.NoError(t, cagg.SynchronizedMove(ckpt, &desc))
-
-	checkpointSet.Add(&desc, ckpt, attribute.String("A", "B"), attribute.String("C", "D"))
-
-	fix.Export(checkpointSet)
-
-	require.Equal(t, `[{"Name":"test.name{R=V,A=B,C=D}","Sum":123}]`, fix.Output())
+	require.Equal(t, `[{"Name":"name.sum{R=V,instrumentation.name=test,A=B,C=D}","Sum":123}]`, fix.Output())
 }
 
 func TestStdoutLastValueFormat(t *testing.T) {
 	fix := newFixture(t)
 
-	checkpointSet := metrictest.NewCheckpointSet(testResource)
+	counter := metric.Must(fix.meter).NewFloat64Counter("name.lastvalue")
+	counter.Add(fix.ctx, 123.456, attribute.String("A", "B"), attribute.String("C", "D"))
 
-	desc := metric.NewDescriptor("test.name", metric.ValueObserverInstrumentKind, number.Float64Kind)
-	lvagg, ckpt := metrictest.Unslice2(lastvalue.New(2))
+	require.NoError(t, fix.cont.Stop(fix.ctx))
 
-	aggregatortest.CheckedUpdate(fix.t, lvagg, number.NewFloat64Number(123.456), &desc)
-	require.NoError(t, lvagg.SynchronizedMove(ckpt, &desc))
-
-	checkpointSet.Add(&desc, ckpt, attribute.String("A", "B"), attribute.String("C", "D"))
-
-	fix.Export(checkpointSet)
-
-	require.Equal(t, `[{"Name":"test.name{R=V,A=B,C=D}","Last":123.456}]`, fix.Output())
+	require.Equal(t, `[{"Name":"name.lastvalue{R=V,instrumentation.name=test,A=B,C=D}","Last":123.456}]`, fix.Output())
 }
 
 func TestStdoutMinMaxSumCount(t *testing.T) {
 	fix := newFixture(t)
 
-	checkpointSet := metrictest.NewCheckpointSet(testResource)
+	counter := metric.Must(fix.meter).NewFloat64Counter("name.minmaxsumcount")
+	counter.Add(fix.ctx, 123.456, attribute.String("A", "B"), attribute.String("C", "D"))
+	counter.Add(fix.ctx, 876.543, attribute.String("A", "B"), attribute.String("C", "D"))
 
-	desc := metric.NewDescriptor("test.name", metric.ValueRecorderInstrumentKind, number.Float64Kind)
+	require.NoError(t, fix.cont.Stop(fix.ctx))
 
-	magg, ckpt := metrictest.Unslice2(minmaxsumcount.New(2, &desc))
-
-	aggregatortest.CheckedUpdate(fix.t, magg, number.NewFloat64Number(123.456), &desc)
-	aggregatortest.CheckedUpdate(fix.t, magg, number.NewFloat64Number(876.543), &desc)
-	require.NoError(t, magg.SynchronizedMove(ckpt, &desc))
-
-	checkpointSet.Add(&desc, ckpt, attribute.String("A", "B"), attribute.String("C", "D"))
-
-	fix.Export(checkpointSet)
-
-	require.Equal(t, `[{"Name":"test.name{R=V,A=B,C=D}","Min":123.456,"Max":876.543,"Sum":999.999,"Count":2}]`, fix.Output())
+	require.Equal(t, `[{"Name":"name.minmaxsumcount{R=V,instrumentation.name=test,A=B,C=D}","Min":123.456,"Max":876.543,"Sum":999.999,"Count":2}]`, fix.Output())
 }
 
 func TestStdoutValueRecorderFormat(t *testing.T) {
 	fix := newFixture(t, stdoutmetric.WithPrettyPrint())
 
-	checkpointSet := metrictest.NewCheckpointSet(testResource)
-
-	desc := metric.NewDescriptor("test.name", metric.ValueRecorderInstrumentKind, number.Float64Kind)
-	aagg, ckpt := metrictest.Unslice2(minmaxsumcount.New(2, &desc))
+	inst := metric.Must(fix.meter).NewFloat64ValueRecorder("name.histogram")
 
 	for i := 0; i < 1000; i++ {
-		aggregatortest.CheckedUpdate(fix.t, aagg, number.NewFloat64Number(float64(i)+0.5), &desc)
+		inst.Record(fix.ctx, float64(i)+0.5, attribute.String("A", "B"), attribute.String("C", "D"))
 	}
+	require.NoError(t, fix.cont.Stop(fix.ctx))
 
-	require.NoError(t, aagg.SynchronizedMove(ckpt, &desc))
-
-	checkpointSet.Add(&desc, ckpt, attribute.String("A", "B"), attribute.String("C", "D"))
-
-	fix.Export(checkpointSet)
-
+	// TODO: Stdout does not export `Count` for histogram, nor the buckets.
 	require.Equal(t, `[
 	{
-		"Name": "test.name{R=V,A=B,C=D}",
-		"Min": 0.5,
-		"Max": 999.5,
-		"Sum": 500000,
-		"Count": 1000
+		"Name": "name.histogram{R=V,instrumentation.name=test,A=B,C=D}",
+		"Sum": 500000
 	}
 ]`, fix.Output())
 }
 
 func TestStdoutNoData(t *testing.T) {
-	desc := metric.NewDescriptor("test.name", metric.ValueRecorderInstrumentKind, number.Float64Kind)
-
-	runTwoAggs := func(agg, ckpt export.Aggregator) {
-		t.Run(fmt.Sprintf("%T", agg), func(t *testing.T) {
+	runTwoAggs := func(aggName string) {
+		t.Run(aggName, func(t *testing.T) {
 			t.Parallel()
 
 			fix := newFixture(t)
-
-			checkpointSet := metrictest.NewCheckpointSet(testResource)
-
-			require.NoError(t, agg.SynchronizedMove(ckpt, &desc))
-
-			checkpointSet.Add(&desc, ckpt)
-
-			fix.Export(checkpointSet)
+			_ = metric.Must(fix.meter).NewFloat64Counter(fmt.Sprint("name.", aggName))
+			require.NoError(t, fix.cont.Stop(fix.ctx))
 
 			require.Equal(t, "", fix.Output())
 		})
 	}
 
-	runTwoAggs(metrictest.Unslice2(lastvalue.New(2)))
-	runTwoAggs(metrictest.Unslice2(minmaxsumcount.New(2, &desc)))
-}
-
-func TestStdoutLastValueNotSet(t *testing.T) {
-	fix := newFixture(t)
-
-	checkpointSet := metrictest.NewCheckpointSet(testResource)
-
-	desc := metric.NewDescriptor("test.name", metric.ValueObserverInstrumentKind, number.Float64Kind)
-
-	lvagg, ckpt := metrictest.Unslice2(lastvalue.New(2))
-	require.NoError(t, lvagg.SynchronizedMove(ckpt, &desc))
-
-	checkpointSet.Add(&desc, lvagg, attribute.String("A", "B"), attribute.String("C", "D"))
-
-	fix.Export(checkpointSet)
-
-	require.Equal(t, "", fix.Output())
+	runTwoAggs("lastvalue")
+	runTwoAggs("minmaxsumcount")
 }
 
 func TestStdoutResource(t *testing.T) {
@@ -270,41 +219,35 @@ func TestStdoutResource(t *testing.T) {
 		}
 	}
 	testCases := []testCase{
-		newCase("R1=V1,R2=V2,A=B,C=D",
+		newCase("R1=V1,R2=V2,instrumentation.name=test,A=B,C=D",
 			resource.NewSchemaless(attribute.String("R1", "V1"), attribute.String("R2", "V2")),
 			attribute.String("A", "B"),
 			attribute.String("C", "D")),
-		newCase("R1=V1,R2=V2",
+		newCase("R1=V1,R2=V2,instrumentation.name=test",
 			resource.NewSchemaless(attribute.String("R1", "V1"), attribute.String("R2", "V2")),
 		),
-		newCase("A=B,C=D",
+		newCase("instrumentation.name=test,A=B,C=D",
 			nil,
 			attribute.String("A", "B"),
 			attribute.String("C", "D"),
 		),
 		// We explicitly do not de-duplicate between resources
 		// and metric labels in this exporter.
-		newCase("R1=V1,R2=V2,R1=V3,R2=V4",
+		newCase("R1=V1,R2=V2,instrumentation.name=test,R1=V3,R2=V4",
 			resource.NewSchemaless(attribute.String("R1", "V1"), attribute.String("R2", "V2")),
 			attribute.String("R1", "V3"),
 			attribute.String("R2", "V4")),
 	}
 
 	for _, tc := range testCases {
-		fix := newFixture(t)
+		ctx := context.Background()
+		fix := newFixtureWithResource(t, tc.res)
 
-		checkpointSet := metrictest.NewCheckpointSet(tc.res)
+		counter := metric.Must(fix.meter).NewFloat64Counter("name.lastvalue")
+		counter.Add(ctx, 123.456, tc.attrs...)
 
-		desc := metric.NewDescriptor("test.name", metric.ValueObserverInstrumentKind, number.Float64Kind)
-		lvagg, ckpt := metrictest.Unslice2(lastvalue.New(2))
+		require.NoError(t, fix.cont.Stop(fix.ctx))
 
-		aggregatortest.CheckedUpdate(fix.t, lvagg, number.NewFloat64Number(123.456), &desc)
-		require.NoError(t, lvagg.SynchronizedMove(ckpt, &desc))
-
-		checkpointSet.Add(&desc, ckpt, tc.attrs...)
-
-		fix.Export(checkpointSet)
-
-		require.Equal(t, `[{"Name":"test.name{`+tc.expect+`}","Last":123.456}]`, fix.Output())
+		require.Equal(t, `[{"Name":"name.lastvalue{`+tc.expect+`}","Last":123.456}]`, fix.Output())
 	}
 }

sdk/export/metric/metrictest/test.go

@@ -1,135 +0,0 @@
-// Copyright The OpenTelemetry Authors
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package metrictest // import "go.opentelemetry.io/otel/sdk/export/metric/metrictest"
-
-import (
-	"context"
-	"errors"
-	"reflect"
-	"sync"
-	"time"
-
-	"go.opentelemetry.io/otel/attribute"
-	"go.opentelemetry.io/otel/metric"
-	"go.opentelemetry.io/otel/metric/number"
-	export "go.opentelemetry.io/otel/sdk/export/metric"
-	"go.opentelemetry.io/otel/sdk/export/metric/aggregation"
-	"go.opentelemetry.io/otel/sdk/resource"
-)
-
-type mapkey struct {
-	desc     *metric.Descriptor
-	distinct attribute.Distinct
-}
-
-// CheckpointSet is useful for testing Exporters.
-// TODO(#872): Uses of this can be replaced by processortest.Output.
-type CheckpointSet struct {
-	sync.RWMutex
-	records  map[mapkey]export.Record
-	updates  []export.Record
-	resource *resource.Resource
-}
-
-// NoopAggregator is useful for testing Exporters.
-type NoopAggregator struct{}
-
-var _ export.Aggregator = (*NoopAggregator)(nil)
-
-// Update implements export.Aggregator.
-func (NoopAggregator) Update(context.Context, number.Number, *metric.Descriptor) error {
-	return nil
-}
-
-// SynchronizedMove implements export.Aggregator.
-func (NoopAggregator) SynchronizedMove(export.Aggregator, *metric.Descriptor) error {
-	return nil
-}
-
-// Merge implements export.Aggregator.
-func (NoopAggregator) Merge(export.Aggregator, *metric.Descriptor) error {
-	return nil
-}
-
-// Aggregation returns an interface for reading the state of this aggregator.
-func (NoopAggregator) Aggregation() aggregation.Aggregation {
-	return NoopAggregator{}
-}
-
-// Kind implements aggregation.Aggregation.
-func (NoopAggregator) Kind() aggregation.Kind {
-	return aggregation.Kind("Noop")
-}
-
-// NewCheckpointSet returns a test CheckpointSet that new records could be added.
-// Records are grouped by their encoded labels.
-func NewCheckpointSet(resource *resource.Resource) *CheckpointSet {
-	return &CheckpointSet{
-		records:  make(map[mapkey]export.Record),
-		resource: resource,
-	}
-}
-
-// Reset clears the Aggregator state.
-func (p *CheckpointSet) Reset() {
-	p.records = make(map[mapkey]export.Record)
-	p.updates = nil
-}
-
-// Add a new record to a CheckpointSet.
-//
-// If there is an existing record with the same descriptor and labels,
-// the stored aggregator will be returned and should be merged.
-func (p *CheckpointSet) Add(desc *metric.Descriptor, newAgg export.Aggregator, labels ...attribute.KeyValue) (agg export.Aggregator, added bool) {
-	elabels := attribute.NewSet(labels...)
-
-	key := mapkey{
-		desc:     desc,
-		distinct: elabels.Equivalent(),
-	}
-	if record, ok := p.records[key]; ok {
-		return record.Aggregation().(export.Aggregator), false
-	}
-
-	rec := export.NewRecord(desc, &elabels, p.resource, newAgg.Aggregation(), time.Time{}, time.Time{})
-	p.updates = append(p.updates, rec)
-	p.records[key] = rec
-	return newAgg, true
-}
-
-// ForEach does not use ExportKindSelected: use a real Processor to
-// test ExportKind functionality.
-func (p *CheckpointSet) ForEach(_ export.ExportKindSelector, f func(export.Record) error) error {
-	for _, r := range p.updates {
-		if err := f(r); err != nil && !errors.Is(err, aggregation.ErrNoData) {
-			return err
-		}
-	}
-	return nil
-}
-
-// Unslice2 takes a slice of []some.Aggregator and returns a slice of []export.Aggregator
-func Unslice2(sl interface{}) (one, two export.Aggregator) {
-	slv := reflect.ValueOf(sl)
-	if slv.Type().Kind() != reflect.Slice {
-		panic("Invalid Unslice2")
-	}
-	if slv.Len() != 2 {
-		panic("Invalid Unslice2: length > 2")
-	}
-	one = slv.Index(0).Addr().Interface().(export.Aggregator)
-	two = slv.Index(1).Addr().Interface().(export.Aggregator)
-	return
-}

sdk/export/metric/metrictest/test_test.go

@@ -1,30 +0,0 @@
-// Copyright The OpenTelemetry Authors
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package metrictest
-
-import (
-	"testing"
-
-	"github.com/stretchr/testify/require"
-)
-
-func TestUnslice(t *testing.T) {
-	in := make([]NoopAggregator, 2)
-
-	a, b := Unslice2(in)
-
-	require.Equal(t, a.(*NoopAggregator), &in[0])
-	require.Equal(t, b.(*NoopAggregator), &in[1])
-}

sdk/metric/correct_test.go

@@ -26,7 +26,6 @@ import (
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/metric"
-	"go.opentelemetry.io/otel/metric/number"
 	export "go.opentelemetry.io/otel/sdk/export/metric"
 	"go.opentelemetry.io/otel/sdk/export/metric/aggregation"
 	metricsdk "go.opentelemetry.io/otel/sdk/metric"
@@ -69,16 +68,6 @@ func init() {
 	otel.SetErrorHandler(testHandler)
 }
 
-// correctnessProcessor could be replaced with processortest.Processor
-// with a non-default aggregator selector.  TODO(#872) use the
-// processortest code here.
-type correctnessProcessor struct {
-	t *testing.T
-	*testSelector
-
-	accumulations []export.Accumulation
-}
-
 type testSelector struct {
 	selector    export.AggregatorSelector
 	newAggCount int
@@ -89,28 +78,24 @@ func (ts *testSelector) AggregatorFor(desc *metric.Descriptor, aggPtrs ...*expor
 	processortest.AggregatorSelector().AggregatorFor(desc, aggPtrs...)
 }
 
-func newSDK(t *testing.T) (metric.Meter, *metricsdk.Accumulator, *correctnessProcessor) {
+func newSDK(t *testing.T) (metric.Meter, *metricsdk.Accumulator, *testSelector, *processortest.Processor) {
 	testHandler.Reset()
-	processor := &correctnessProcessor{
-		t:            t,
-		testSelector: &testSelector{selector: processortest.AggregatorSelector()},
-	}
+	testSelector := &testSelector{selector: processortest.AggregatorSelector()}
+	processor := processortest.NewProcessor(
+		testSelector,
+		attribute.DefaultEncoder(),
+	)
 	accum := metricsdk.NewAccumulator(
 		processor,
 		testResource,
 	)
 	meter := metric.WrapMeterImpl(accum, "test")
-	return meter, accum, processor
-}
-
-func (ci *correctnessProcessor) Process(accumulation export.Accumulation) error {
-	ci.accumulations = append(ci.accumulations, accumulation)
-	return nil
+	return meter, accum, testSelector, processor
 }
 
 func TestInputRangeCounter(t *testing.T) {
 	ctx := context.Background()
-	meter, sdk, processor := newSDK(t)
+	meter, sdk, _, processor := newSDK(t)
 
 	counter := Must(meter).NewInt64Counter("name.sum")
 
@@ -120,19 +105,19 @@ func TestInputRangeCounter(t *testing.T) {
 	checkpointed := sdk.Collect(ctx)
 	require.Equal(t, 0, checkpointed)
 
-	processor.accumulations = nil
+	processor.Reset()
 	counter.Add(ctx, 1)
 	checkpointed = sdk.Collect(ctx)
-	sum, err := processor.accumulations[0].Aggregator().(aggregation.Sum).Sum()
-	require.Equal(t, int64(1), sum.AsInt64())
+	require.Equal(t, map[string]float64{
+		"name.sum//R=V": 1,
+	}, processor.Values())
 	require.Equal(t, 1, checkpointed)
-	require.Nil(t, err)
 	require.Nil(t, testHandler.Flush())
 }
 
 func TestInputRangeUpDownCounter(t *testing.T) {
 	ctx := context.Background()
-	meter, sdk, processor := newSDK(t)
+	meter, sdk, _, processor := newSDK(t)
 
 	counter := Must(meter).NewInt64UpDownCounter("name.sum")
 
@@ -142,16 +127,16 @@ func TestInputRangeUpDownCounter(t *testing.T) {
 	counter.Add(ctx, 1)
 
 	checkpointed := sdk.Collect(ctx)
-	sum, err := processor.accumulations[0].Aggregator().(aggregation.Sum).Sum()
-	require.Equal(t, int64(1), sum.AsInt64())
+	require.Equal(t, map[string]float64{
+		"name.sum//R=V": 1,
+	}, processor.Values())
 	require.Equal(t, 1, checkpointed)
-	require.Nil(t, err)
 	require.Nil(t, testHandler.Flush())
 }
 
 func TestInputRangeValueRecorder(t *testing.T) {
 	ctx := context.Background()
-	meter, sdk, processor := newSDK(t)
+	meter, sdk, _, processor := newSDK(t)
 
 	valuerecorder := Must(meter).NewFloat64ValueRecorder("name.exact")
 
@@ -164,19 +149,19 @@ func TestInputRangeValueRecorder(t *testing.T) {
 	valuerecorder.Record(ctx, 1)
 	valuerecorder.Record(ctx, 2)
 
-	processor.accumulations = nil
+	processor.Reset()
 	checkpointed = sdk.Collect(ctx)
 
-	count, err := processor.accumulations[0].Aggregator().(aggregation.Count).Count()
-	require.Equal(t, uint64(2), count)
+	require.Equal(t, map[string]float64{
+		"name.exact//R=V": 3,
+	}, processor.Values())
 	require.Equal(t, 1, checkpointed)
 	require.Nil(t, testHandler.Flush())
-	require.Nil(t, err)
 }
 
 func TestDisabledInstrument(t *testing.T) {
 	ctx := context.Background()
-	meter, sdk, processor := newSDK(t)
+	meter, sdk, _, processor := newSDK(t)
 
 	valuerecorder := Must(meter).NewFloat64ValueRecorder("name.disabled")
 
@@ -184,12 +169,12 @@ func TestDisabledInstrument(t *testing.T) {
 	checkpointed := sdk.Collect(ctx)
 
 	require.Equal(t, 0, checkpointed)
-	require.Equal(t, 0, len(processor.accumulations))
+	require.Equal(t, map[string]float64{}, processor.Values())
 }
 
 func TestRecordNaN(t *testing.T) {
 	ctx := context.Background()
-	meter, _, _ := newSDK(t)
+	meter, _, _, _ := newSDK(t)
 
 	c := Must(meter).NewFloat64Counter("name.sum")
 
@@ -200,7 +185,7 @@ func TestRecordNaN(t *testing.T) {
 
 func TestSDKLabelsDeduplication(t *testing.T) {
 	ctx := context.Background()
-	meter, sdk, processor := newSDK(t)
+	meter, sdk, _, processor := newSDK(t)
 
 	counter := Must(meter).NewInt64Counter("name.sum")
 
@@ -217,7 +202,7 @@ func TestSDKLabelsDeduplication(t *testing.T) {
 		keysB = append(keysB, attribute.Key(fmt.Sprintf("B%03d", i)))
 	}
 
-	var allExpect [][]attribute.KeyValue
+	allExpect := map[string]float64{}
 	for numKeys := 0; numKeys < maxKeys; numKeys++ {
 
 		var kvsA []attribute.KeyValue
@@ -238,29 +223,24 @@ func TestSDKLabelsDeduplication(t *testing.T) {
 
 		counter.Add(ctx, 1, kvsA...)
 		counter.Add(ctx, 1, kvsA...)
-		allExpect = append(allExpect, expectA)
+		format := func(attrs []attribute.KeyValue) string {
+			str := attribute.DefaultEncoder().Encode(newSetIter(attrs...))
+			return fmt.Sprint("name.sum/", str, "/R=V")
+		}
+		allExpect[format(expectA)] += 2
 
 		if numKeys != 0 {
 			// In this case A and B sets are the same.
 			counter.Add(ctx, 1, kvsB...)
 			counter.Add(ctx, 1, kvsB...)
-			allExpect = append(allExpect, expectB)
+			allExpect[format(expectB)] += 2
 		}
 
 	}
 
 	sdk.Collect(ctx)
 
-	var actual [][]attribute.KeyValue
-	for _, rec := range processor.accumulations {
-		sum, _ := rec.Aggregator().(aggregation.Sum).Sum()
-		require.Equal(t, sum, number.NewInt64Number(2))
-
-		kvs := rec.Labels().ToSlice()
-		actual = append(actual, kvs)
-	}
-
-	require.ElementsMatch(t, allExpect, actual)
+	require.EqualValues(t, allExpect, processor.Values())
 }
 
 func newSetIter(kvs ...attribute.KeyValue) attribute.Iterator {
@@ -295,7 +275,7 @@ func TestDefaultLabelEncoder(t *testing.T) {
 
 func TestObserverCollection(t *testing.T) {
 	ctx := context.Background()
-	meter, sdk, processor := newSDK(t)
+	meter, sdk, _, processor := newSDK(t)
 	mult := 1
 
 	_ = Must(meter).NewFloat64ValueObserver("float.valueobserver.lastvalue", func(_ context.Context, result metric.Float64ObserverResult) {
@@ -342,15 +322,11 @@ func TestObserverCollection(t *testing.T) {
 	})
 
 	for mult = 0; mult < 3; mult++ {
-		processor.accumulations = nil
+		processor.Reset()
 
 		collected := sdk.Collect(ctx)
-		require.Equal(t, collected, len(processor.accumulations))
+		require.Equal(t, collected, len(processor.Values()))
 
-		out := processortest.NewOutput(attribute.DefaultEncoder())
-		for _, rec := range processor.accumulations {
-			require.NoError(t, out.AddAccumulation(rec))
-		}
 		mult := float64(mult)
 		require.EqualValues(t, map[string]float64{
 			"float.valueobserver.lastvalue/A=B/R=V": -mult,
@@ -367,13 +343,13 @@ func TestObserverCollection(t *testing.T) {
 			"float.updownsumobserver.sum/C=D/R=V": mult,
 			"int.updownsumobserver.sum//R=V":      -mult,
 			"int.updownsumobserver.sum/A=B/R=V":   mult,
-		}, out.Map())
+		}, processor.Values())
 	}
 }
 
 func TestSumObserverInputRange(t *testing.T) {
 	ctx := context.Background()
-	meter, sdk, processor := newSDK(t)
+	meter, sdk, _, processor := newSDK(t)
 
 	// TODO: these tests are testing for negative values, not for _descending values_. Fix.
 	_ = Must(meter).NewFloat64SumObserver("float.sumobserver.sum", func(_ context.Context, result metric.Float64ObserverResult) {
@@ -392,7 +368,7 @@ func TestSumObserverInputRange(t *testing.T) {
 	collected := sdk.Collect(ctx)
 
 	require.Equal(t, 0, collected)
-	require.Equal(t, 0, len(processor.accumulations))
+	require.EqualValues(t, map[string]float64{}, processor.Values())
 
 	// check that the error condition was reset
 	require.NoError(t, testHandler.Flush())
@@ -400,7 +376,7 @@ func TestSumObserverInputRange(t *testing.T) {
 
 func TestObserverBatch(t *testing.T) {
 	ctx := context.Background()
-	meter, sdk, processor := newSDK(t)
+	meter, sdk, _, processor := newSDK(t)
 
 	var floatValueObs metric.Float64ValueObserver
 	var intValueObs metric.Int64ValueObserver
@@ -450,12 +426,8 @@ func TestObserverBatch(t *testing.T) {
 
 	collected := sdk.Collect(ctx)
 
-	require.Equal(t, collected, len(processor.accumulations))
+	require.Equal(t, collected, len(processor.Values()))
 
-	out := processortest.NewOutput(attribute.DefaultEncoder())
-	for _, rec := range processor.accumulations {
-		require.NoError(t, out.AddAccumulation(rec))
-	}
 	require.EqualValues(t, map[string]float64{
 		"float.sumobserver.sum//R=V":    1.1,
 		"float.sumobserver.sum/A=B/R=V": 1000,
@@ -471,12 +443,12 @@ func TestObserverBatch(t *testing.T) {
 		"float.valueobserver.lastvalue/C=D/R=V": -1,
 		"int.valueobserver.lastvalue//R=V":      1,
 		"int.valueobserver.lastvalue/A=B/R=V":   1,
-	}, out.Map())
+	}, processor.Values())
 }
 
 func TestRecordBatch(t *testing.T) {
 	ctx := context.Background()
-	meter, sdk, processor := newSDK(t)
+	meter, sdk, _, processor := newSDK(t)
 
 	counter1 := Must(meter).NewInt64Counter("int64.sum")
 	counter2 := Must(meter).NewFloat64Counter("float64.sum")
@@ -497,16 +469,12 @@ func TestRecordBatch(t *testing.T) {
 
 	sdk.Collect(ctx)
 
-	out := processortest.NewOutput(attribute.DefaultEncoder())
-	for _, rec := range processor.accumulations {
-		require.NoError(t, out.AddAccumulation(rec))
-	}
 	require.EqualValues(t, map[string]float64{
 		"int64.sum/A=B,C=D/R=V":     1,
 		"float64.sum/A=B,C=D/R=V":   2,
 		"int64.exact/A=B,C=D/R=V":   3,
 		"float64.exact/A=B,C=D/R=V": 4,
-	}, out.Map())
+	}, processor.Values())
 }
 
 // TestRecordPersistence ensures that a direct-called instrument that
@@ -514,7 +482,7 @@ func TestRecordBatch(t *testing.T) {
 // that its encoded labels will be cached across collection intervals.
 func TestRecordPersistence(t *testing.T) {
 	ctx := context.Background()
-	meter, sdk, processor := newSDK(t)
+	meter, sdk, selector, _ := newSDK(t)
 
 	c := Must(meter).NewFloat64Counter("name.sum")
 	b := c.Bind(attribute.String("bound", "true"))
@@ -526,7 +494,7 @@ func TestRecordPersistence(t *testing.T) {
 		sdk.Collect(ctx)
 	}
 
-	require.Equal(t, 4, processor.newAggCount)
+	require.Equal(t, 4, selector.newAggCount)
 }
 
 func TestIncorrectInstruments(t *testing.T) {
@@ -536,7 +504,7 @@ func TestIncorrectInstruments(t *testing.T) {
 	var observer metric.Int64ValueObserver
 
 	ctx := context.Background()
-	meter, sdk, _ := newSDK(t)
+	meter, sdk, _, processor := newSDK(t)
 
 	// Now try with uninitialized instruments.
 	meter.RecordBatch(ctx, nil, counter.Measurement(1))
@@ -562,12 +530,13 @@ func TestIncorrectInstruments(t *testing.T) {
 
 	collected = sdk.Collect(ctx)
 	require.Equal(t, 0, collected)
+	require.EqualValues(t, map[string]float64{}, processor.Values())
 	require.Equal(t, metricsdk.ErrUninitializedInstrument, testHandler.Flush())
 }
 
 func TestSyncInAsync(t *testing.T) {
 	ctx := context.Background()
-	meter, sdk, processor := newSDK(t)
+	meter, sdk, _, processor := newSDK(t)
 
 	counter := Must(meter).NewFloat64Counter("counter.sum")
 	_ = Must(meter).NewInt64ValueObserver("observer.lastvalue",
@@ -579,12 +548,8 @@ func TestSyncInAsync(t *testing.T) {
 
 	sdk.Collect(ctx)
 
-	out := processortest.NewOutput(attribute.DefaultEncoder())
-	for _, rec := range processor.accumulations {
-		require.NoError(t, out.AddAccumulation(rec))
-	}
 	require.EqualValues(t, map[string]float64{
 		"counter.sum//R=V":        100,
 		"observer.lastvalue//R=V": 10,
-	}, out.Map())
+	}, processor.Values())
 }

sdk/metric/processor/basic/basic_test.go

@@ -29,8 +29,8 @@ import (
 	"go.opentelemetry.io/otel/metric/number"
 	export "go.opentelemetry.io/otel/sdk/export/metric"
 	"go.opentelemetry.io/otel/sdk/export/metric/aggregation"
-	"go.opentelemetry.io/otel/sdk/export/metric/metrictest"
 	sdk "go.opentelemetry.io/otel/sdk/metric"
+	"go.opentelemetry.io/otel/sdk/metric/aggregator/aggregatortest"
 	"go.opentelemetry.io/otel/sdk/metric/processor/basic"
 	"go.opentelemetry.io/otel/sdk/metric/processor/processortest"
 	processorTest "go.opentelemetry.io/otel/sdk/metric/processor/processortest"
@@ -301,7 +301,7 @@ func TestBasicInconsistent(t *testing.T) {
 	b = basic.New(processorTest.AggregatorSelector(), export.StatelessExportKindSelector())
 
 	desc := metric.NewDescriptor("inst", metric.CounterInstrumentKind, number.Int64Kind)
-	accum := export.NewAccumulation(&desc, attribute.EmptySet(), resource.Empty(), metrictest.NoopAggregator{})
+	accum := export.NewAccumulation(&desc, attribute.EmptySet(), resource.Empty(), aggregatortest.NoopAggregator{})
 	require.Equal(t, basic.ErrInconsistentState, b.Process(accum))
 
 	// Test invalid kind:
@@ -326,7 +326,7 @@ func TestBasicTimestamps(t *testing.T) {
 	afterNew := time.Now()
 
 	desc := metric.NewDescriptor("inst", metric.CounterInstrumentKind, number.Int64Kind)
-	accum := export.NewAccumulation(&desc, attribute.EmptySet(), resource.Empty(), metrictest.NoopAggregator{})
+	accum := export.NewAccumulation(&desc, attribute.EmptySet(), resource.Empty(), aggregatortest.NoopAggregator{})
 
 	b.StartCollection()
 	_ = b.Process(accum)

sdk/metric/processor/processortest/test.go

@@ -121,6 +121,11 @@ func (p *Processor) Values() map[string]float64 {
 	return p.output.Map()
 }
 
+// Reset clears the state of this test processor.
+func (p *Processor) Reset() {
+	p.output.Reset()
+}
+
 // Checkpointer returns a checkpointer that computes a single
 // interval.
 func Checkpointer(p *Processor) export.Checkpointer {